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An edible composite film was developed and applied for ready-to-eat sea cucumber storage to improve the product quality. The PAC film base is first prepared by mixing 0.5 % glycerin (GL) with 4 % polyvinyl alcohol (PVA) and 1 % arginine-modified chitosan (Arg-CTS) in the same volume. After the addition of nano-ZnO (ZnO) and thymol (Thy) to the PAC film base, the mechanical properties and functions were tested. Compared to the PAC film, the PAC-ZnO-ThyH composite film showed a 1.34-fold increase in the DPPH scavenging rate and a 2.19-fold increase in the ABTS scavenging rate. Contrary to the PAC film, the inhibition zone diameter of Escherichia coli and Staphylococcus aureus significantly increased by 2.35 and 4.08 folds in the PAC-Zno-ThyH film, respectively. After applying the PAC-ZnO-ThyH film to store ready-to-eat sea cucumber for 10 days, there was a significant reduction in weight loss, total volatile basic nitrogen (TVB-N), and lipid oxidation levels to 1.47 and 1.26 folds to the Ctrl group. After preservation, the hardness and chewiness of ready-to-eat sea cucumber were maintained at 1079.62 ± 138.86 N and 913.73 ± 175.79 N, respectively. The novel PAC-ZnO-ThyH composite film can be used as an active food packaging for promising seafood applications., Competing Interests: Declaration of competing interest All authors have read the declaration of interests and declare that they have no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Industrial and academic chemical pollutants such as Eriochrome Black-T (EBT) and murexide dyes are widely used in academic institution as well as industries, when eluted into rivers, delineate the ill effect on human and aquatic life. Herein, green and ecofriendly synthesis of silver doped-Zinc oxide nanoparticles (Ag/ZnO NPs) and chitosan coated Ag/ZnO nanoparticles (CS/Ag/ZnO NPs) using Bergera koenigii extract to solve environmental issues have been reported for the first time. Spherical and agglomerated particles with crystalline flakes like morphology of Ag/ZnO NPs and CS/Ag/ZnO NPs respectively have been ascertained by Scanning electron morphology (SEM) analyses and XRD. XRD analysis revealed the average crystallite size of 42.16 nm and 48.45 nm for Ag/ZnO NPs with 5 % and 10 % Ag concentration respectively, lesser than crystallite size of 47.394 nm and 52.38 nm for CS-5 % Ag/ZnO NC and CS-10 % Ag/ZnO NC respectively. All the synthesized NPs and NC demonstrated remarkable antibacterial potential against both gram +ve and gram -ve bacteria. Additionally, all the materials showed very high time-dependent photocatalytic degradation activity (>98 %) of EBT and murexide in 12 min. Remarkably, all active nano-catalysts exhibit high durability, and displayed recyclability for >8 cycles. In nutshell, chitosan coated nano-catalyst showed drastic improvement in photocatalytic and antibacterial activities., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: The world society is still suffering greatly from waterborne infections, with developing countries bearing most of the morbidity and death burden, especially concerning young children. Moreover, microbial resistance is one of the most prevalent global problems that extends the need for self-medication and the healing period, or it may be linked to treatment failure that results in further hospitalization, higher healthcare expenses, and higher mortality rates. Thus, innovative synthesis of new antimicrobial materials is required to preserve the environment and enhance human health., Results: The present study highlighted a simple and cost-effective approach to biosynthesize a chitosan/graphene oxide/zinc oxide nanocomposite (CS/GO/ZnO) alone and immobilized in a macroporous cryogel as a new antimicrobial agent. Bacillus subtilis ATCC 6633 was used as a safe and efficient bio-nano-factory during biosynthesis. The formation of CS/GO/ZnO was confirmed and characterized using different analyses including ultraviolet-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), selective area diffraction pattern (SADP), Zeta analyses, scanning electron microscope (SEM) and transmission electron microscopy (TEM). GO combined with ZnO NPs successfully and displayed an adsorption peak at 358 nm. The XRD results showed the crystalline composition of the loaded ZnO NPs on GO sheets. FTIR spectrum confirmed the presence of proteins during the synthesis which act as stabilizing and capping agents. The nanocomposite has a high negative surface charge (-32.8 ± 5.7 mV) which increases its stability. SEM and TEM showing the size of biosynthesized ZnO-NPs was in the range of 40-50 nm. The CS/GO/ZnO alone or immobilized in cryogel revealed good antimicrobial activities against B. cereus ATCC 14,579, Escherichia coli ATCC 25,922, and Candida albicans ATCC 10,231 in a dose-dependent manner. The CS/GO/ZnO cryogel revealed higher antimicrobial activity than GO/ZnO nanocomposite and standard antibiotics (amoxicillin and miconazole) with inhibition zones averages of 24.33 ± 0.12, 15.67 ± 0.03, and 17.5 ± 0.49 mm, respectively. The MIC values of the prepared nanocomposite against B. cereus, E. coli, and C. albicans were 80, 80, and 90 µg/ml compared to standard drugs (90, 120 and 150 µg/ml, respectively). According to the TEM ultrastructure studies of nanocomposite-treated microbes, treated cells had severe deformities and morphological alterations compared to the untreated cells including cell wall distortion, the separation between the cell wall and plasma membrane, vacuoles formation moreover complete cell lyses were also noted. In the cytotoxicity test of CS/GO/ZnO alone and its cryogel, there was a significant reduction (p˂0.05) in cell viability of WI-38 normal lung cell line after the concentration of 209 and 164 µg/ml, respectively. It showed the low toxic effect of the nanocomposite and its cryogel on the WI-38 line which implies its safety. In addition, water treatment with the CS/GO/ZnO cryogel decreased turbidity (0.58 NTU), total coliform (2 CFU/100 ml), fecal coliform (1 CFU/100 ml), fecal Streptococcus (2 CFU/100 ml), and heterotrophic plate counts (53 CFU/1 ml) not only in comparison with the chlorine-treated samples (1.69 NTU, 4 CFU/100 ml, 6 CFU/100 ml, 57 CFU/100 ml, and 140 CFU/1 ml, respectively) but also with the raw water samples (6.9 NTU, 10800 CFU/100 ml, 660 CFU/100 ml, 800 CFU/100 ml, and 4400 CFU/1 ml, respectively). Moreover, cryogel significantly decreased the concentration of different heavy metals, especially cobalt compared to chlorine (0.004 ppm, 0.002 ppm, and 0.001 ppm for raw water, chlorine-treated, and cryogel-treated groups, respectively) which helped in the reduction of their toxic effects., Conclusion: This study provides an effective, promising, safe, and alternative nanocomposite to treat different human and animal pathogenic microbes that might be used in different environmental, industrial, and medical applications., (© 2024. The Author(s).)

In this research, a novel active food packaging material was developed by blending starch, chitosan, and plant-based mucilage with zinc oxide nanoparticles. The polymeric nanocomposite film, created by incorporating zinc oxide nanoparticles into the mixture using a straightforward approach, was analyzed for its structural and functional attributes using FTIR, XRD, SEM, and TGA/DSC. These analyses revealed a robust interaction between the polymers' functional groups and the nanoparticles, forming a stable film. The film's mechanical properties, including tensile strength and Young's modulus, were high. It also showed reduced wettability and water solubility, enhancing water resistance. The biodegradability rate was 100 %. Antibacterial tests against Bacillus sp. and Pseudomonas sp. showed significant inhibition zones of 26 mm and 30 mm, respectively, demonstrating strong antibacterial effectiveness. The film's non-target toxicity was assessed through phytotoxicity experiments on Vigna angularis and soil nutrient evaluations, with no negative impact on plant growth or soil health observed. These results indicate that this nanocomposite is a safe, biocompatible option for food packaging., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study employed a precipitation method to synthesize zinc oxide@quaternised chitosan nanoparticles (ZnO@QAC NPs) containing different concentrations of zinc oxide, namely ZnO@QAC-2, ZnO@QAC-4, and ZnO@QAC-6. Subsequently, these nanoparticles were incorporated into matrices consisting of gelatine (Gn) and polyvinyl alcohol (PVA) separately, which were prepared by casting to form a biodegradable film. We assessed the physicochemical properties of ZnO@QAC NPs and physicochemical characteristics, antioxidant properties, antimicrobial activity and grape preservation efficacy of the film. Compared to the control group, the films showed a reduction in water vapor permeability by >9.38 %, an increase in tensile strength by over 51.95 %, over 70 % scavenging of ABTS free radicals, and good biocompatibility. Additionally, the antimicrobial activity of the films containing ZnO@QAC-6 increased by 37.6 %. In the grape preservation experiment, the weight loss of grapes wrapped in ZnO@QAC-2 film was reduced by 40.13 % on day 15 compared to unwrapped grapes. These results demonstrate that ZnO@QAC/PVA/Gn films have considerable potential for food packaging applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

To mitigate environmental impacts in food preservation, the development of a multifunctional membrane for packaging is of importance. In this study, we have successfully fabricated a nanofibrous membrane using an eco-friendly electrospinning technique, comprising polyvinyl alcohol (PVA), chitosan (CS), and tannic acid (TA). The resulting nanofibrous membranes were crosslinked with glutaraldehyde (GA) and surface modified with ZnO. Our findings demonstrate that the crosslinking process enhances water resistance, reduces water vapor permeability, improves tensile strength (from 3 to 18 MPa), and enhances thermal stability (increasing decomposition temperature from 225 °C to 310 °C). Furthermore, the incorporation of TA and ZnO provides antioxidant properties to the membrane, effectively preventing food decomposition caused by UV-induced oxidation. Additionally, CS, TA, and ZnO synergistically exhibit a remarkable antibacterial effect with a bacteriostasis rate exceeding 99.9 %. The strawberry fresh-keeping experiment further confirms that our developed membrane significantly extends shelf life by up to 6 days. Moreover, cytotoxicity assays confirm the non-toxic nature of these membranes. The innovative significance of this study lies in proposing a robust GA-PVA/CS/TA@ZnO nanofibrous membrane with excellent mechanical properties, biocompatibility, and multiple functionalities including antibacterial, anti-ultraviolet, and anti-oxidation capabilities. It has tremendous potential for applications in active food packaging materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Despite cisplatin's long history as a cornerstone in cancer therapy, both acquired chemoresistance and significant impacts on healthy tissues limit its use. Hepatotoxicity is one of its side effects. Adjunct therapies have shown promise in not only attenuating liver damage caused by cisplatin but also in enhancing the efficacy of chemotherapy. In this context, a new quaternary ammonium chitosan Schiff base (QACSB) was synthesized and applied as an encapsulating agent for the in-situ synthesis of QACSB-ZnO nanocomposite., Material and Methods: Thirty male albino rats were classified into Group 1 (control) distilled water, Group 2 (Cisplatin-treated) (12 mg/kg, i.p), and Group 3 (QACSB-ZnO NCs/cisplatin-treated) (150 mg/kg/day QACSB-ZnO NCs, i.p) for 14 days + a single dose of cisplatin. Liver functions, tissue TNF-α, MDA, and GSH were measured as well as histopathological and immunohistochemical studies were performed., Results: The QACSB-ZnO NCs significantly restore liver functions, tissue TNF-α, MDA, and GSH levels (p < 0.001). Histopathological examination showed patchy necrosis in the cisplatin-treated group versus other groups. The QACSB-ZnO NCs showed a weak TGF-β1 (score = 4) and a moderate Bcl-2 immunohistochemistry expression (score = 6) versus the CP group., Conclusions: QACSB-ZnO NCs have been shown to protect the liver from cisplatin-induced hepatotoxicity., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The current study explores biodegradable packaging materials that have high food quality assurance, as food deterioration is mostly caused by UV degradation and oxidation, which can result in bad flavor and nutrition shortages. Thus, new multifunctional zinc oxide nanoparticles/tannic acid (ZnO@TA) with antioxidant and antibacterial activities were incorporated into polyvinyl alcohol/chitosan (PVA/CH) composite films with different ratios (1%, 3%, and 5% based on the total dry weight of the film) via a solution blending method in a neutral aqueous solution. Additionally, ZnO nanoparticles have unique antibacterial mechanisms through the generation of excessive reactive oxygen species (ROS) that may lead to intensify pathogen resistance to conventional antibacterial agents. Thus, minimizing the negative effects caused by excessive levels of ROS may be possible by developing unique, multifunctional ZnO nanoparticles with antioxidant potential via coordination bond between tannic acid and ZnO nanoparticles (ZnO@TA). ZnO@TA nanoparticles were examined using Fourier-transform infrared (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The effect of the incorporation of ZnO@TA nanoparticles on the barrier, mechanical, thermal, antioxidant, antimicrobial, and UV blocking characteristics of chitosan/polyvinyl alcohol (ZnO@TA@CH/PVA) films was investigated. The lowest water vapor and oxygen permeability and the maximum antioxidant capacity% are 31.98 ± 1.68 g mm/m 2  kPa day, 0.144 ± 5.03 × 10 -2  c.c/m 2 .day, and 69.35 ± 1.6%, respectively, which are related to ZnO@TA(50)@CH/PVA. Furthermore, ZnO@TA(50)@CH/PVA film exhibits the maximum UV shielding capacity of UVB (99.994). ZnO@TA(50) @PVA/CH films displayed better tensile strength and Young`s modulus of 48.72 ± 0.23 MPa and 2163.46 ± 61.4 MPa, respectively, than the other film formulations. However, elongation % at break exhibited the most reduced value of 19.62 ± 2.3%. ZnO@TA@CH/PVA film exhibits the largest inhibition zones of 11 ± 1.0, 12.3 ± 0.57, and 13.6 ± 0.57 mm against Staphylococcus aureus, Aspergillus flavus, and Candida albicans, respectively. In accordance with these results, ZnO@TA@CH/PVA films could be utilized for food preservation for the long-term., (© 2024. The Author(s).)

Staphylococcus aureus (S. aureus) is considered as one of the challenging ulcer infections in diabetic patients especially those who have acquired antibiotic-resistant infections. Nanotechnology products have enormous potential to treat diseases including infectious diseases. As chitosan and zinc oxide (ZnO) nanoparticles (NPs) have harbored a high antimicrobial effect, this survey was aimed to synthesize chitosan, ZnO, and ZnO-Urtica. diocia (ZnO-U. diocia) NPs, and to assess their antimicrobial effects and their influence on virulence genes expression in S. aureus isolates from diabetic ulcers. The antibacterial effect of NPs was detected by microdilution method. The most frequently components in U. diocia aqueous extract were linalool,4-thujanol, camphor, carvacrol, propanedioic acid, and di(butyl) phthalate. More than 95% of clinical S. aureus isolates were resistant to several antibiotics including erythromycin, cefoxitin, clindamycin, and ciprofloxacin. The most resistant isolates were S. aureus ATDS 52, ATDS 53, F5232, and F91. The lowest MIC and MBC by the NPs on the isolates was detected as 0.128 g/mL and 0.178 g/mL, respectively. A significant decrease of 90% in the expression rates of lukED and RNAIII genes was reported for S. aureus isolates treated with the NPs. The synthetized ZnO-U. diocia and chitosan NPs can be proposed as a reliable and effective antimicrobial agent targeting diabetic ulcers infections caused by S. aureus because of its high effects on the bacterial growth and virulence genes expression., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Drug-resistant bacterial infection of cutaneous wounds causes great harm to the human body. These infections are characterized by a microenvironment with recalcitrant bacterial infections, persistent oxidative stress, imbalance of immune regulation, and suboptimal angiogenesis. Treatment strategies available to date are incapable of handling the healing dynamics of infected wounds. A Schiff base and borate ester cross-linked hydrogel, based on phenylboronic acid-grafted chitosan (CS-PBA), dibenzaldehyde-grafted poly(ethylene glycol), and tannic acid (TA), is fabricated in the present study. Customized phenylboronic acid-modified zinc oxide nanoparticles (ZnO) are embedded in the hydrogel prior to gelation. The CPP@ZnO-P-TA hydrogel effectively eliminates methicillin-resistant Staphylococcus aureus (MRSA) due to the pH-responsive release of Zn 2+ and TA. Killing is achieved via membrane damage, adenosine triphosphate reduction, leakage of intracellular components, and hydrolysis of bacterial o-nitrophenyl-β-d-galactopyranoside. The CPP@ZnO-P-TA hydrogel is capable of scavenging reactive oxygen and nitrogen species, alleviating oxidative stress, and stimulating M2 polarization of macrophages. The released Zn 2+ and TA also induce neovascularization via the PI3K/Akt pathway. The CPP@ZnO-P-TA hydrogel improves tissue regeneration in vivo by alleviating inflammatory responses, stimulating angiogenesis, and facilitating collagen deposition. These findings suggest that this versatile hydrogel possesses therapeutic potential for the treatment of MRSA-infected cutaneous wounds., (© 2024 Wiley‐VCH GmbH.)

This study aimed to develop and assess a chitosan biomedical antibacterial gel ZincOxide-GrapheneOxide/Chitosan/β-Glycerophosphate (ZnO-GO/CS/β-GP) loaded with nano-zinc oxide (ZnO) and graphene oxide (GO), known for its potent antibacterial properties, biocompatibility, and sustained drug release. ZnO nanoparticles (ZnO-NPs) were modified and integrated with GO sheets to create 1% and 3% ZnO-GO/CS/β-GP thermo-sensitive hydrogels based on ZnO-GO to Chitosan (CS) mass ratio. Gelation time, pH, structural changes, and microscopic morphology were evaluated. The hydrogel's antibacterial efficacy against Porphyromonas gingivalis, biofilm biomass, and metabolic activity was examined alongside its impact (MC3T3-e1). The findings of this study revealed that both hydrogel formulations exhibited temperature sensitivity, maintaining a neutral pH. The ZnO-GO/CS/β-GP formulation effectively inhibited P. gingivalis bacterial activity and biofilm formation, with a 3% ZnO-GO/CS/β-GP antibacterial rate approaching 100%. MC3T3-e1 cells displayed good biocompatibility when cultured in the hydrogel extract.The ZnO-GO/CS/β-GP thermo-sensitive hydrogel demonstrates favorable physical and chemical properties, effectively preventing P. gingivalis biofilm formation. It exhibits promising biocompatibility, suggesting its potential as an adjuvant therapy for managing and preventing peri-implantitis, subject to further clinical investigations.

The development of nanomaterials has been speedily established in recent years, yet nanoparticles synthesized by traditional methods suffer unacceptable toxicity and the sustainability of the procedure for synthesizing such nanoparticles is inadequate. Consequently, green biosynthesis, which employs biopolymers, is gaining attraction as an environmentally sound alternative to less sustainable approaches. Chitosan-encapsulated nanoparticles exhibit exceptional antibacterial properties, offering a wide range of uses. Chitosan, obtained from shrimp shells, aided in the environmentally friendly synthesis of high-purity zinc oxide nanoparticles (ZnO NPs) with desirable features such as the extraction yield (41%), the deacetylation (88%), and the crystallinity index (74.54%). The particle size of ZnO NPs was 12 nm, while that of chitosan-ZnO NPs was 21 nm, and the bandgap energies of these nanomaterials were 3.98 and 3.48, respectively. The strong antibacterial action was demonstrated by ZnO NPs, chitosan-ZnO NPs, and chitosan-ZnO/PVP, particularly against Gram-positive bacteria, making them appropriate for therapeutic use. The photocatalytic degradation abilities were also assessed for all nanoparticles. At a concentration of 6 × 10 -5  M, chitosan removed 90.5% of the methylene blue (MB) dye, ZnO NPs removed 97.4%, chitosan-coated ZnO NPs removed 99.6%, while chitosan-ZnO/PVP removed 100%. In the case of toluidine blue (TB), at a concentration of 4 × 10 -3  M, the respective efficiencies were 96.8%, 96.8%, 99.5%, and 100%, respectively. Evaluation of radical scavenger activity revealed increased scavenging of ABTS and DPPH radicals by chitosan-ZnO/PVP compared to individual zinc oxide or chitosan-ZnO, where the IC50 results were 0.059, 0.092, 0.079 mg/mL, respectively, in the ABTS test, and 0.095, 0.083, 0.061, and 0.064 mg/mL in the DPPH test, respectively. Moreover, in silico toxicity studies were conducted to predict the organ-specific toxicity through ProTox II software. The obtained results suggest the probable safety and the absence of organ-specific toxicity with all the tested samples., (© 2024. The Author(s).)

Naringenin (NRG) inhibits the fungal 17β-hydroxysteroid dehydrogenase accountable for ergosterol synthesis in Candida albicans (C. albicans), a causative agent for cutaneous candidiasis. In present research, NRG was complexed with ZnO nanomaterial (NRG-Zn 2+ ) to synthesize NRG-Zn 2+ nanocomposites. The particle size and ζ-potential of NRG-Zn 2+ nanocomposites were respectively estimated to be 180.33 ± 1.22-nm and - 3.92 ± 0.35-mV. In silico data predicted the greater affinity of NRG-Zn 2+ nanocomposite for 14α-demethylase and ceramide in comparison to NRG alone. Later, NRG-Zn 2+ nanocomposites solution was transformed in to naringenin-zinc oxide nanocomposites loaded chitosan gel (NRG-Zn-CS-Gel) with viscosity and firmness of 854806.7 ± 52386.43 cP and 698.27 ± 10.35 g, respectively. The ex-vivo skin permeation demonstrated 70.49 ± 5.22% skin retention, significantly greater (P < 0.05) than 44.48 ± 3.06% of naringenin loaded chitosan gel (NRG-CS-Gel) and 31.24 ± 3.28% of naringenin solution (NRG Solution). NRG-Zn-CS-Gel demonstrated 6.71 ± 0.84% permeation of NRG with a flux value of 0.046 ± 0.01-µg/cm 2 /h. The MIC 50 of NRG-Zn-CS-Gel against C. albicans was estimated to be 0.156-µg/mL with FICI (fractional inhibitory concentration index) of 0.018 that consequently exhibited synergistic efficacy. Further, NRG-Zn-CS-Gel demonstrated superior antifungal efficacy in C. albicans induced cutaneous candidiasis infection in Balb/c mice. The fungal burden in NRG-Zn-CS-Gel treated group was 109 ± 25 CFU/mL, significantly lower (P < 0.05) than positive control (2260 ± 446 CFU/mL), naringenin loaded chitosan gel (NRG-CS-Gel; 928 ± 127 CFU/mL) and chitosan gel (CS-Gel; 2116 ± 186 CFU/mL) treated mice. Further, histopathology examination and cytokine profiling of TNF-α, IL-1β and IL-10 revealed the healing of skin and inflammation associated with cutaneous candidiasis infection. In conclusion, NRG-Zn-CS-Gel may be a potential candidate for translating in to a clinical viable topical nanotherapeutic., (© 2024. The Author(s), under exclusive licence to American Association of Pharmaceutical Scientists.)

Objective: The purpose of this study is to investigate the taste masking of Paracetamol granules in the range of 250-850 µm, coated by two nanocomposites prepared from Eudragit ® E100, nanozinc oxide, and nanochitosan, respectively, from 1 to 5% by the weight of the granules., Methods: In this study, Paracetamol granules were coated in several formulas with two different types of nanocomposites (polymeric and mineral) on two sizes of granules to reduce bitter taste and with the FBC method and pH-sensitive polymers (Eudragit ® E100)., Results: The effect of nanoparticles (Nano zinc oxide and Nanochitosan) on taste-masking Paracetamol was studied with dissolution-coated granules in vitro by simulating in the oral (pH 6.8) range. Based on the results of the studies, the rate of drug release was confirmed by the taste test, and the formulated granule with 5% nano-chitosan (F14) had the best bitter taste mask function of all samples. These results were also confirmed by scanning electron microscopy (SEM) analysis, which showed a smoother and more stable surface than the samples obtained from other formulations., Conclusion: In the comparison of the release of two types of nanocomposites in the dissolution test, it was shown that the type B granules of Paracetamol's 5% nano-chitosan-coated granule (F14) were released 99% less than Paracetamol's 5% nano-ZnO-coated granule (F11). and Paracetamol's 1% nano-chitosan-coated granule (F12) was released 91% less than Paracetamol's 1% nano-ZnO-coated granule (F9). The results showed that nano-chitosan-coated granules have better coverage of bitter taste instead of nano-ZnO.

A dynamic chitosan-based ZnO nanocomposite (NC) was fabricated via a cost-effective formulation and an eco-friendly procedure utilizing Cissus quadrangularis (CQ) plant extract. This study investigates the antimicrobial and antioxidant properties, together with the cytocompatibility aspects of chitosan-incorporated ZnO nanocomposite (CS-ZnO/CQE). The formation and structural morphology of the nanocomposites were examined using FTIR, UV-Vis, XRD, XPS, BET, TGA, SEM, and TEM techniques. The antibacterial test results demonstrated the greatest inhibitory zone diameter against S. aureus (19 ± 1.00 mm) and E. coli (17 ± 1.05 mm), assessed through agar well diffusion method. Also, the composite exhibited a DPPH inhibition rate of 78.7 ± 0.34 %, indicating its high effectiveness in neutralizing free radicals. In addition, the nanocomposite exhibited less toxicity towards human erythrocytes, HDF and HEK-293 cells as a result of the biocompatibility exhibited by CS, ZnO, and CQ plant extract. Likewise, it has exceptional cell migratory capacity and possesses biodegradability factors. These observations strongly suggest the potential of CS-ZnO/CQE as a cutting-edge antibacterial and antioxidant agent to be implemented in the medical sector., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Global concerns due to the negative impacts of untreatable wounds, as well as the growing population of these patients, emphasize the critical need for advancements in the wound healing materials and techniques. Nanotechnology offers encouraging avenues for improving wound healing process. In this context, nanoparticles (NPs) and certain natural materials, including chitosan (CS) and aloe vera (AV), have demonstrated the potential to promote healing effects. The objective of this investigation is to assess the effect of novel fabricated nanocomposite gel containing CS, AV, and zinc oxide NPs (ZnO NPs) on the wound healing process. The ZnO NPs were synthesized and characterized by X-ray diffraction and electron microscopy. Then, CS/AV gel with different ratios was prepared and loaded with ZnO NPs. The obtained formulations were characterized in vitro based on an antimicrobial study, and the best formulations were used for the animal study to assess their wound healing effects in 21 days. The ZnO NPs were produced with an average 33 nm particle size and exhibited rod shape morphology. Prepared gels were homogenous with good spreadability, and CS/AV/ZnO NPs formulations showed higher antimicrobial effects against Staphylococcus aureus , Escherichia coli, and Pseudomonas aeruginosa . The wound healing findings showed significant wound area reduction in the CS/AV/ZnO NPs group compared to negative control at day 21. Histopathological assessment revealed the advantageous impact of this formulation across various stages of the wound healing process, including collagen deposition (CS/AV/ZnO NPs (2 : 1), 76.6 ± 3.3 compared to negative control, 46.2 ± 3.7) and epitheliogenesis (CS/AV/ZnO NPs (2 : 1), 3 ± 0.9 compared to negative control, 0.8 ± 0.8). CS/AV gel-loaded ZnO NPs showed significant effectiveness in wound healing and would be suggested as a promising formulation in the wound healing process. Further assessments are warranted to ensure the robustness of our findings., Competing Interests: There are no conflicts of interest, and we clarify any conflict between corresponding authors and co-authors., (Copyright © 2024 Hasanain Adel Alawadi et al.)

Chitosan-based nanocomposites (CS NCs) are gaining considerable attention as multifaceted antifungal agents. This study investigated the antifungal activity of NCs against two phytopathogenic strains: Fusarium solani (F. solani) and Alternaria solani (A. solani). Moreover, it sheds light on their underlying mechanisms of action. The NCs, CS-ZnO, CS-CuO, and CS-SiO 2 , were characterized using advanced methods. Dynamic and electrophoretic light scattering techniques revealed their size range (60-170 nm) and cationic nature, as indicated by the positive zeta potential values (from +16 to +22 mV). Transmission electron microscopy revealed the morphology of the NCs as agglomerates formed between the chitosan and oxide components. X-ray diffraction patterns confirmed crystalline structures with specific peaks indicating their constituents. Antifungal assessments using the agar diffusion technique demonstrated significant inhibitory effects of the NCs on both fungal strains (1.5 to 4-fold), surpassing the performance of the positive control, nystatin. Notably, the NCs exhibited superior antifungal potency, with CS-ZnO NCs being the most effective. A. solani was the most sensitive strain to the studied agents. Furthermore, the tested NCs induced oxidative stress in fungal cells, which elevated stress biomarker levels, such as superoxide dismutase (SOD) activity and protein carbonyl content (PCC), 2.5 and 6-fold for the most active CS-CuO in F. solani respectively. Additionally, they triggered membrane lipid peroxidation up to 3-fold higher compared to control, a process that potentially compromises membrane integrity. Laurdan fluorescence spectroscopy highlighted alterations in the molecular organization of fungal cell membranes induced by the NCs. CS-CuO NCs induced a membrane rigidifying effect, while CS-SiO 2 and CS-ZnO could rigidify membranes in A. solani and fluidize them in F. solani. In summary, this study provides an in-depth understanding of the interactions of CS-based NCs with two fungal strains, showing their antifungal activity and offering insights into their mechanisms of action. These findings emphasize the potential of these NCs as effective and versatile antifungal agents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study aims to develop pH-sensitive and controlled release of ciprofloxacin from ciprofloxacin-loaded grafted chitosan-coated zinc oxide nanoparticles (Cip@Gchit/Zn-NPs) for the treatment of bacterial infections in the human colon. For this aim, first, the chitosan-g-poly(itaconic acid) [Chit-g-poly (Itac)] was synthesized via grafting of itaconic acid onto chitosan in the presence of cerium ammonium nitrate (CAN) under an inert atmosphere using conventional methods, while zinc oxide nanoparticles (Zn-NPs) were prepared via sol-gel technique. Characterization of the synthesized Cip@Gchit/Zn-NPs was analyzed using XRD, FT-IR, SEM, TGA, and zeta potential analysis. The antibacterial efficacy of Cip@Gchit/Zn-NPs against three pathogenic bacteria, namely Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus, was superior to that of tetracycline reference drugs, as evidenced by larger inhibition zones. Cytotoxicity assessment of Cip@Gchit/Zn-NPs on the human chondrocyte cell line C28/I2 via MTT assay revealed 100 % cell viability at a concentration of 500 μg/mL. The loading efficiency of ciprofloxacin into Gchit/Zn-NPs was evaluated at various ratios, demonstrating lower loading efficiency; however, sustained release of ciprofloxacin from Cip@Gchit/Zn-NPs was excellent, with 98.13 % release observed at pH 7.2 over 10 h. Kinetic analysis of ciprofloxacin release followed the first-order kinetic models., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study investigates the creation and analysis of chitosan-zinc oxide (CS-ZnO) nanocomposites, exploring their effectiveness in inhibiting bacteria. Two synthesis approaches, physical and chemical, were utilized. The CS-ZnO nanocomposites demonstrated strong antibacterial properties, especially against Staphylococcus aureus, a Gram-positive bacterium. Chemically synthesized nanocomposites (CZ10 and CZ100) exhibited larger inhibition zones (16.4 mm and 18.7 mm) compared to physically prepared CS-Z5 and CS-Z20 (12.2 mm and 13.8 mm) against Staphylococcus aureus. Moreover, CZ nanocomposites displayed enhanced thermal stability, with decomposition temperatures of 281°C and 290°C, surpassing CS-Z5 and CS-Z20 (260°C and 258°C). The residual mass percentages at 800°C were significantly higher for CZ10 and CZ100 (58% and 61%) than for CS-Z5 and CS-Z20 (36% and 34%). UV-Visible spectroscopy revealed reduced band gaps in the CS-ZnO nanocomposites, indicating improved light absorption. Transmission electron microscopy (TEM) confirmed uniform dispersion of ZnO nanoparticles within the chitosan matrix. In conclusion, this research underscores the impressive antimicrobial potential of CS-ZnO nanocomposites, especially against Gram-positive bacteria, and highlights their enhanced thermal stability. These findings hold promise for diverse applications in industries such as medicine, pharmaceuticals, and materials science, contributing to the development of sustainable materials with robust antimicrobial properties., (© 2024. The Author(s).)

The increasing aging of the population has elevated bone defects to a significant threat to human life and health. Aerogel, a biomimetic material similar to an extracellular matrix (ECM), is considered an effective material for the treatment of bone defects. However, most aerogel scaffolds suffer from immune rejection and poor anti-inflammatory properties and are not well suited for human bone growth. In this study, we used electrospinning to prepare flexible ZnO-SiO 2 nanofibers with different zinc concentrations and further assembled them into three-dimensional composite aerogel scaffolds. The prepared scaffolds exhibited an ordered pore structure, and chitosan (CS) was utilized as a cross-linking agent with aspirin (ASA). Interestingly, the 1%ZnO-SiO 2 /CS@ASA scaffolds not only exhibited good biocompatibility, bioactivity, anti-inflammation, and better mechanical properties but also significantly promoted vascularization and osteoblast differentiation in vitro . In the mouse cranial defect model, the BV/TV data showed a higher osteogenesis rate in the 1%ZnO-SiO 2 /CS group (10.94 ± 0.68%) and the 1%ZnO-SiO 2 /CS@ASA group (22.76 ± 1.83%), compared with the control group (5.59 ± 2.08%), and in vivo studies confirmed the ability of 1%ZnO-SiO 2 /CS@ASA to promote in situ regeneration of new bone. This may be attributed to the fact that Si 4+ , Zn 2+ , and ASA released from 1%ZnO-SiO 2 /CS@ASA scaffolds can promote angiogenesis and bone formation by stimulating the interaction between endothelial cells (ECs) and BMSCs, as well as inducing macrophage differentiation to the M2 type and downregulating the expression of pro-inflammatory factor (TNF-α) to modulate local inflammatory response. These exciting results and evidence suggest that it provides a new and effective strategy for the treatment of bone defects.

Phase change microcapsules are known for their latent heat storage capability. However, the efficient absorption and utilization of solar energy by these microcapsules remains a significant challenge. In this study, we successfully prepared composite phase change microcapsules containing ZnO-Ag nanospheres, chitosan, and paraffin. These microcapsules demonstrated remarkable photothermal conversion efficiency. ZnO was found to effectively absorb ultraviolet light, while the plasmonic resonance of Ag was utilized to absorb and make use of light energy in the visible region. Moreover, due to the synergistic absorption and reflection of electromagnetic waves by ZnO-Ag nanoparticles and graphene, the well-dispersed chitosan/ZnO-Ag composite microcapsules and graphene in the fabric coating demonstrated exceptional electromagnetic shielding performance. In addition, the coated fabric based on composite microcapsules exhibited excellent antibacterial properties, effectively inhibiting the growth of bacteria such as S. aureus and E. coli. This antibacterial performance adds to their potential applications in various fields. These multifunctional phase change microcapsules offer vast potential for the effective utilization of solar energy, serving as efficient photothermal conversion and energy storage materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this work, a multifunctional preservative film of ZnO/carboxymethyl starch/chitosan (ZnO/CMS/CS) with the unique "Steel Wire Mesh" structure is fabricated by the chemical crosslinked of ZnO NPs, CMS and CS. Unlike traditional nano-filled polymer film, the formation of the "Steel Wire Mesh" structure of ZnO/CMS/CS film is based on the synergistic effect of ZnO NPs filled CMS/CS and the coordination crosslinked between CMS/CS and Zn 2+ derived from ZnO NPs. Thanks to the "Steel Wire Mesh" structure, the tensile strength and water vapor barrier of 2.5ZnO/10CMS/CS film are 2.47 and 1.73 times than that of CS film, respectively. Furthermore, the transmittance of 2.5ZnO/10CMS/CS film during antifogging test is close to 89 %, confirming its excellent antifogging effects. And the 2.5ZnO/10CMS/CS film also exhibits excellent long-acting antibacterial activity (up to 202 h), so it can maintain the freshness and appearance of strawberries at least 5 days. More importantly, the 2.5ZnO/10CMS/CS film is sensitive to humidity changes, which achieves real-time humidity monitoring of the fruit storage environment. Note that the preparation method of the film is safe, simple and environmentally friendly, and its excellent degradation performance will not bring any problems of food safety and environmental pollution., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Wound infections and delayed complications after caesarean section surgical procedure to mothers would have a prevalence of discomfort, stress and dissatisfaction in the postpartum period. In this report, one-pot synthesis is used for the preparation of chitosan (CS)-based copper nanoparticles (nCu), which was used for the preparation of zinc oxide (ZnO) hydrogel as wound dressing materials after surgery. The antibacterial activity of (CS-nCu/ZnO) developed hydrogels was studied zone of inhibition, against gram-positive and gram-negative bacteria. The antibacterial activity of the CS-nCu/ZnO hydrogel demonstrated that nanoformulated hydrogel materials have provided excellent bactericidal action against clinically approved bacterial pathogens. The biocompatibility and in vitro wound healing potential of the developed wound closure materials were studied by MTT assay and wound scratch assay methods, respectively. The MTT assay and cell migration assay results demonstrated that CS-nCu/ZnO hydrogel material induces cell compatibility and effective cell proliferation ability. These findings suggest that the CS-nCu/ZnO hydrogel outperforms CS-ZnO in terms of wound healing and could be used as a wound closure material in caesarean section wound treatment., (© 2023 The Authors. International Wound Journal published by Medicalhelplines.com Inc and John Wiley & Sons Ltd.)

Modification surface of chitosan nanoparticles using ZnO nanoparticles is important interest in drug delivery because of the beneficial properties. In this study, we proposed a chitosan/ZnO nanocomposite for the targeted delivery of antibacterial peptide (LL37). Synthesized LL37-loaded chitosan/ZnO nanocomposite (CS/ZnO/LL37-NCs) was based on the ionotropic gelation method. The antibacterial activity of the synthesized platform versus Methicillin-resistant Staphylococcus aureus (MRSA) was determined by the microdilution method in 10 mM sodium phosphate buffer. The biofilm formation inhibitory was also evaluated using microtiter plate method. In addition, the ability of CS/ZnO/LL37-NCs on the icaA gene expression level was assessed by the Real-Time PCR. The loading and release investigations confirmed the suitability of CS/ZnO-NCs for LL37 encapsulation. Results showed 6 log 10 CFU/ml reduction in MRSA treated with the CS/ZnO/LL37-NPs. Moreover, CS/ZnO/LL37-NCs showed 81 % biofilm formation inhibition than LL37 alone. Also, icaA gene expression decreased 1-fold in the face of CS/ZnO/LL37-NCs. In conclusion, the modification surface of chitosan nanoparticles with ZnO nanoparticles is a suitable chemical platform for the delivery of LL37 that could be used as a promising nanocarrier for enhancing the delivery of antibacterial peptide and improving the antibacterial activity of LL37., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

This study aimed to formulate and characterize the experimental lollipops containing chitosan- zinc oxide nanoparticles (CH-ZnO NPs) and investigate their antimicrobial effects against some cariogenic bacteria. The CH-ZnO NPs were synthesized and characterized by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) analysis, and Transmission electron microscope (TEM). Then, four groups were made, including lollipops coated with 2 and 4 ml of CH-ZnO NPs, 0.7 ml CH-ZnO NPs incorporated lollipops, and those with no CH-ZnO NPs. Their antibacterial effectiveness against Streptococcus mutans and Lactobacillus acidophilus was evaluated by direct contact test and tissue culture plate method in planktonic and biofilm phases, respectively. Chlorhexidine mouthrinse (CHX) was used as a positive control group. In the planktonic phase, the antibacterial properties of both groups coated with CH-ZnO NPs were comparable and significantly higher than incorporated ones. There was no significant difference between CHX and the lollipops coated with 4 ml of NPs against S. mutans and CHX and two coated groups against L. acidophilus. None of the experimental lollipops in the biofilm phase could reduce both bacteria counts. The experimental lollipops coated with 2 and 4 ml of CH-ZnO NPs could reveal favorable antimicrobial properties against two cariogenic bacteria in the planktonic phase., (© 2023. The Author(s).)

Two novel chemically cross-linked chitosan hydrogels were successfully prepared via insertion of oxalyl dihydrazide moieties between chitosan Schiff's base chains (OCsSB) and between chitosan chains (OCs). For more modification, two different concentrations of ZnO nanoparticles (ZnONPs) were loaded into OCs to obtain OCs/ZnONPs-1 % and OCs/ZnONPs-3 % composites. The prepared samples were recognized using elemental analyses, FTIR, XRD, SEM, EDS and TEM. Their inhibitory action against microbes and biofilms were classified as: OCs/ZnONPs-3 % > OCs/ZnONPs-1 % > OCs > OCsSB > chitosan. OCs has inhibition activity similar to Vancomycin of minimum inhibitory concentration (MIC) value of 3.9 μg/mL against P. aeruginosa. OCs exhibited minimum biofilm inhibitory concentration (MBIC) values (from 31.25 to 62.5 μg/mL) less than that of OCsSB (from 62.5 to 250 μg/mL) which lower than that of chitosan (from 500 to 1000 μg/mL) against S. epidermidis, P. aeruginosa and C. albicans. OCs/ZnNPs-3 % showed MIC value (that caused 100 % inhibition of Clostridioides difficile, C. difficile) of 0.48 μg/mL much lower than Vancomycin (1.95 μg/mL). Both OCs and OCs/ZnONPs-3 % composite were safe on normal human cells. Thus, inclusion of oxalyl dihydrazide and ZnONPs into chitosan greatly reinforced its antimicrobial activity. This is a good strategy to accomplish adequate systems for competing traditional antibiotics., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023. Published by Elsevier B.V.)

The current study was aimed at the assessment of the effect of chitosan-ZnO/Selenium nanoparticles scaffold on infected wound healing and care of paediatric surgery treatment. The nanoparticle scaffolds were developed from sources such as chitosan (CS), different concentrations of zinc oxide (ZnO), and Selenium (SeNPs) nanoparticles by freeze-drying method. The structural and chemical properties of nanoparticles were investigated by UV-Vis, fourier transform infrared spectroscopy (FTIR), and phase identification by x-ray diffraction analysis. The surface morphology of CS, chitosan-ZnO (CS-ZnO) and chitosan-ZnO/SeNPs was analysed using a scanning electron microscope. The incorporation of ZnO and SeNPs along with CS polymer induces antioxidant and antimicrobial functions. The bacterial susceptibility to nanoparticle scaffolds against Escherichia coli and Staphylococcus aureus showed the excellent antibacterial effects of ZnO and SeNPs. In-vitro studies of fibroblast of NIH 3 T3 and HaCaT cell lines revealed the biocompatibility, cell adhesion, cell viability, and proliferation of scaffold in the wound site. Also, results of in-vivo studies strongly enhanced collagen synthesis, re-epithelialization, and rapid wound closure. Thus, the synthesised chitosan-ZnO/SeNPs nanoparticle scaffold resulted in significant improvement in histopathological indices in the full thickness of wound healing after nursing care of paediatric fracture surgery., (© 2023 The Authors. International Wound Journal published by Medicalhelplines.com Inc (3M) and John Wiley & Sons Ltd.)

Metal nanoparticles have been tremendously utilised, such as; antibacterial and anticancer agents. Although metal nanoparticles exhibits antibacterial and anticancer activity, but the drawback of toxicity on normal cells limits their clinical applications. Therefore, improving the bioactivity of hybrid nanomaterial (HNM) and minimizing toxicity is of paramount importance for biomedical applications. Herein, a facile and simple double precipitation method was used to develop biocompatible and multifunctional HNM from antimicrobial chitosan, curcumin, ZnO and TiO 2 . In HNM, biomolecules chitosan and curcumin were used to control the toxicity of ZnO and TiO 2 and improve their biocidal properties. The cytotxicological properties of the HNM was studied against human breast cancer (MDA-MB-231) and fibroblast (L929) cell lines. The antimicrobial activity of the HNM was examined against Escherichia coli and Staphylococcus aureus bacteria, via the well-diffusion method. In addition, the antioxidant property was evaluated by the radical scavenging method. These findings actively, support the ZTCC HNM potential, as an innovative biocidal agent for applications in the clinical and healthcare sectors., Competing Interests: Declaration of competing interest There are no conflicts of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The present research work aimed at synthesizing chitosan-coated Zinc oxide nanocomposites (NS-CS/ZnONCs) by a bio-inspired method using an aqueous extract of Nigella sativa (NS) seeds and employing a quality-by-design approach (Box-Behnken design). The biosynthesized NS-CS/ZnONCs were physicochemically characterized and subjected to their in-vitro and in-vivo therapeutic potential. The zeta potential value of -11.2 mV and -12.6 mV indicated the stability of NS-mediated synthesized zinc oxide nanoparticles (NS-ZnONPs) and NS-CS/ZnONCs, respectively. The particle size of NS-ZnONPs and NS-CS/ZnONCs were 288.1 nm and 130.2 nm, respectively, with PDI of 0.198 and 0.158. NS-ZnONPs and NS-CS/ZnONCs showed superior radical scavenging abilities, excellent α-amylase, and α-glucosidase inhibitory activities. Also, NS-ZnONPs and NS-CS/ZnONCs demonstrated effective antibacterial activity against selected pathogens. Furthermore, NS-ZnONPs and NS-CS/ZnONCs demonstrated significant (p < 0.001) wound closure with 93.00 ± 0.43 % and 95.67 ± 0.43 % on the 15 th day of treatment at the dose of 14 mg/wound, compared to 93.42 ± 0.58 % of standard. Collagen turnover was represented by hydroxyproline, which was shown to be significantly (p < 0.001) higher in the NS-ZnONPs (60.70 ± 1.44 mg/g of tissue) and NS-CS/ZnONCs (66.10 ± 1.23 mg/g of tissue) treatment groups than in the control group (47.7 ± 0.81 mg/g of tissue). Thus the NS-ZnONPs and NS-CS/ZnONCs could effectively develop promising drugs to inhibit pathogens and chronic tissue repair., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Shailendra Shivaji Gurav has patent CHITOSAN AND ZINC OXIDE NANOCOMPOSITE pending to Licensee., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Biopolymer-based food packaging films are gaining increasing popularity, as consumers' demands for sustainable alternatives and environmental concerns associated with synthetic plastic packaging grow. In this research work, chitosan-based active antimicrobial films reinforced with eugenol nanoemulsion (EuNE), Aloe vera gel, and zinc oxide nanoparticles (ZnONPs) were fabricated and characterized for their solubility, microstructure, optical properties, antimicrobial and antioxidant activities. The rate of release of EuNE from the fabricated films was also evaluated to determine active nature of the films. The EuNE droplet size was about 200 nm, and they were uniformly distributed throughout the film matrices. Incorporation of EuNE in chitosan drastically improved UV-light barrier property of the fabricated composite film by 3 to 6 folds, while maintaining their transparency. The XRD spectra of the fabricated films showed good compatibility between the chitosan and the incorporated active agents. The incorporation of ZnONPs significantly improved their antibacterial properties against foodborne bacteria and tensile strength about 2-folds, whereas incorporation of EuNE and AVG improved DPPH scavenging activities of the chitosan film up to 95 %, respectively., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Nanofibrous composite membranes consisting of polyvinyl alcohol (PVA), sodium alginate (SA), chitosan-nano zinc oxide nanoparticles (CS-Nano-ZnO) and curcumin (Cur) were prepared by ultrasonic processing and electrospinning. When the ultrasonic power was set to 100 W, the prepared CS-Nano-ZnO had a minimum size (404.67 ± 42.35 nm) and a generally uniform particle size distribution (PDI = 0.32 ± 0.10). The composite fiber membrane with Cur: CS-Nano-ZnO mass ratio of 5:5 exhibited the best water vapor permeability, strain and stress. Furthermore, the inhibitory rates against Escherichia coli and Staphylococcus aureus were 91.93 ± 2.07 % and 93.00 ± 0.83 %, respectively. The Kyoho grape fresh-keeping trial revealed that grape berries wrapped with composite fiber membrane still maintained good quality and a higher rate of good fruit (60.25 ± 1.46 %) after 12 days of storage. The shelf life of grape was extended by at least 4 days. Thus, nanofibrous composite membranes based on CS-Nano-ZnO and Cur was expected to be used as an active material for food packaging., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

The emergence of multidrug-resistant (MDR) bacteria has made wound infection treatment difficult, calling for novel strategies for effective elimination of bacteria in wounds and promoting their recovery. Herein, we report a novel chitosan antibacterial sponge combining zinc oxide particles (ZnO) and the photosensitizer chlorin e6 (Ce6), named CS-ZnO/Ce6 sponge for combating multidrug-resistant bacteria and treating skin abscesses. The fabricated CS-ZnO/Ce6 sponge had porous structure with high porosity, conducive to absorbing the wound exudate. Meanwhile, the hemostatic property of this sponge enabled it to stop the continuous bleeding of the wound. Upon 660 nm light irradiation, the CS-ZnO/Ce6 sponge exhibited an instant photodynamic bactericidal effect against several typical MDR strains, and the presence of ZnO could continuously inhibit bacterial growth. In addition, local remedy of methicillin-resistant Staphylococcus aureus (MRSA)-infected mice with CS-ZnO/Ce6 sponge with light irradiation caused a potent immediate bacterial killing effect and prolonged bacteriostasis in mice with skin abscesses, leading to the rapid recovery of the wound. The biocompatibility of the CS-ZnO/Ce6 sponge in mice was also verified by histological examination of the main organs. Collectively, the CS-ZnO/Ce6 sponge with broad-spectrum antibacterial activity and long-term bacterial inhibition potential could be useful for treating microbial infections and accelerating wound healing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Chitosan (CS) is one of the most abundant biopolymers in nature with superior properties such as biocompatibility, biodegradability, lack of toxicity, antimicrobial activity, acceleration of wound healing, and stimulation of the immune system. In this study, chitosan was extracted from the exoskeletons of beetles (Pimelia payraudi latreille) and then used for the biosynthesis of highly pure MgO NPs and ZnO NPs by a facile greener route. The extracted chitosan exhibited excellent physicochemical properties, including high extraction yield (39%), high degree of deacetylation (90%), low ash content (1%), high fat-binding capacity (366%), and unusual crystallinity index (51%). The MgO NPs and ZnO NPs exhibited a spherical morphology with crystallite sizes of 17 nm and 29 nm, particle sizes of about 20-70 nm and 30-60 nm, and band gap energies of 4.43 and 3.34 eV, respectively. Antibacterial assays showed that the extracted chitosan exhibited high antibacterial activity against Gram-positive and -negative bacteria, while ZnO NPs showed much stronger antibacterial activity against Gram-positive bacteria than against Gram-negative bacteria. For MgO NPs, the antibacterial activity against Gram-positive bacteria was lower than against Gram-negative bacteria. The results suggest that the synthesized MgO NPs and ZnO NPs are excellent antibacterial agents for therapeutic applications., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

A novel chitosan Schiff base derivative (CVZ) doped with ZnO nanoparticles (ZnONPs) was synthesized and investigated. The corrosion protection performance was evaluated via electrochemical measurements and surface analyses. Compared to the undoped derivative (CV), the results show that the corrosion inhibition efficiency of CVZ sharply increases from 67.7 % to 99.6 %. The surface mean roughness decreases from 1.2350 μm of the blank sample to 0.7004 μm with CVZ protection. Additionally, the inhibition mechanism of the inhibitor and the synergistic effect between CV and ZnONPs were discussed. The strategy of organic/inorganic hybrid and the synergistic effect can inspire the development of chitosan as a green corrosion inhibitor with low concentration and high efficiency., Competing Interests: Declaration of competing interest We all declared that they have no conflict of interest to this work. We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

In the current study, bi-metal oxide hybrid nanocomposites prepared by cerium oxide (CeO 2 ) nanoparticles are included into chitosan-ZnO composites for developing the potential materials of dressing the wound. The wound healing effect of prepared hybrid nanocomposites was evaluated regarding the surface morphology, functional groups, thermal degradation and composite size. The antimicrobial activity of chitosan-ZnO/CeO 2 hybrid nano composites was tested against the pathogens of Staphylococcus aureus and Escherichia coli. The hybrid nanocomposites containing CeO 2 -based chitosan and ZnO nanoparticles were taken for optimum dressing included in the vivo studies on the excisional wounds in wistar rats. After 2 weeks, it is seen that the wound treated with CS-ZnO/CeO 2 hybrid nano composites consists of the significant dressing of nearly 100% compared with control which showed nearly 65% of wound closure. Finally, our reported results gave the proof in supporting the availability of CS-ZnO/CeO 2 hybrid nanocomposites contains the dressing of the wounds for the treatment., (© 2022 The Authors. International Wound Journal published by Medicalhelplines.com Inc (3M) and John Wiley & Sons Ltd.)

Bacterial infection is a major complication associated with bioimplant materials, including titanium (Ti) based orthopedic joints and dental implants. Thus, the fabrication of Ti surfaces with antibacterial activity is highly important. Black phosphorus (BP) is a recently discovered promising two-dimensional semiconductor for various biomedical applications due to its tunable bandgap and physicochemical properties. The present study aimed to synthesize zinc oxide (ZnO) laden BP nanohybrids (NH) and their coatings on a Ti bioimplant surface for improving the antibacterial activities against pathogenic bacteria with and without near-infrared (NIR) light irradiation. Nanohybrids were produced with the slightly oxidized BP NF and electrostatically laden ZnO NP. The produced BP-ZnO NH was a NIR active nanomaterial (up to ∼1000 nm), demonstrating a photothermal effect against bacterial infection and showing improved activity by damaging the cell membrane towards S. aureus in comparison to E. coli. Ti surface coated with BP-ZnO NH embedded chitosan (CS) demonstrated better antibacterial activity than BP NF, especially with NIR light treatment. Additionally, the produced BP nanoflakes and BP-ZnO NH, and their coatings over the Ti surface were found to be toxic at a negligible level. Electrochemical studies revealed the high corrosion resistance of the Ti surface coated with the synthesized antibacterial agents without altering its characteristic passive behavior. Owing to the interactions between the charged groups between chitosan and cell surfaces, a slight increase in antibacterial activities was noticed. Chitosan-based coating matrix embedded with nanoagents has adhered well over the Ti surface due to its inherent film-forming and high adhesion properties., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

In this study, hesperidin (HSP) biological agent, which has strong antioxidant properties, was successfully transferred to ZnO nanoparticles, which were first synthesized by the hydrothermal method. Then, chitosan (CS)/ZnO-HSP nanocomposites were produced by adding different ratios of the ZnO-HSPs to the biodegradable CS biopolymer by hydrothermal method. The resulting materials were characterized using various biophysical strategies, including X-ray diffraction (XRD), Fourier transform infrared spectrometry, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy. The mean particle size of ZnO was estimated to be 29 nm from the XRD calculations and SEM measurements. The effect of the ZnO-HSPs on the thermal properties of pure CS was investigated by thermogravimetric analysis and differential scanning calorimetry techniques, and improvements were noted in the thermal properties of CS. While the T g value of CS was 81 °C, this value increased by 13-94 °C with the addition of 6 wt% by weight of the ZnO-HSP. The antibacterial effect of materials was determined by the disc diffusion method. The ZnO-HSPs added to the CS caused the nanocomposites to have a remarkable effect against Escherichia coli and Staphylococcus aureus microorganisms. While the inhibition diameter of the CS against E. coli was 18.3, the same value increased to 22.3 for the composite containing 6 wt% the ZnO-HSP. The HSP increased the antioxidant capacity of both the ZnO-HSP particles and the CS/ZnO-HSP nanocomposites, reducing the toxic effects of ZnO nanoparticles. Thus, it was determined that the CS/ZnO-HSP nanocomposites did not have any cytotoxicity in healthy human cells. The fact that the produced nanocomposites exhibit antibacterial activity and do not harm human cells shows that they can be a safe product for health. From all these results, this triple hybrid system is hoped that it will be used in biomedical applications as a naturally-sourced, environmentally friendly, and cost-effective composite biomaterial by combining its antimicrobial and strong antioxidant properties.

Antimicrobial-resistant is a major challenge in to treat infected wounds, and new formulations should be produced. Citral (Citl), chitosan (Chsn), and zinc oxide (ZnO) nanoparticles may accelerate the wound healing process in terms of their antibacterial properties. This new study aimed to investigate the effects of ointments produced from ZnO/Chsn/Citl nanoparticles (NPs) to treat the infected wounds. Following the preparation of ZnO/Chsn/Citl-NPs, swelling behavior, the release of citral, toxicity, and antibacterial properties were evaluated. Base ointment, mupirocin, and ointments made from Chsn-NPs, Chsn/Citl-NPs, and ZnO/Chsn/Citl-NPs were used to treat the mice. The ointments' effects on wound contraction, total bacterial count, and immunofluorescence staining for TNF-α, TGF-β, and bFGF were tested. The synthesis of ZnO/Chsn/Citl-NPs was validated by XRD, FT-IR, DLS, and TEM findings. In higher dilutions, chitosan/citral and ZnO/Chsn/Citl-NPs indicated better antibacterial activity. Nanoparticles were safe up to concentration of the 0.5 mg/mL. The mice in Chsn/Citl and ZnO/Chsn/Citl-NPs treated groups showed higher (P < 0.05) wound contraction ratio and expressions for bFGF, and lower total bacterial count and expressions for TGF-β and TNF-α compared to control mice. Ointments prepared from ZnO/Chsn/Citl-NPs could compete with the commercial ointment of mupirocin and can be used to treat infected wounds after clinical studies., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Recently, nanocomposites produced from clays and metals coated with chitosan have shown wound healing activity. This study aimed to synthesize the zinc oxide/malachite nanocomposite (ZnO/Mlt-NC) and its coating form with chitosan (ZnO/Mlt/Chsn-NC). Physicochemical characterization of the produced nanocomposites was investigated. Biomedical effects of nanocomposites, such as in vivo and in vitro antibacterial activity, antioxidant properties, cytotoxicity, and modulation in the gene expressions of interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-10 (IL-10), and transforming growth factor-β (TGF-β) and histopathological parameters, were also investigated. Expression intensities of basic fibroblast growth factor (bFGF) and tumor necrosis factor alpha (TNF-α) were also investigated by immunofluorescence staining. To investigate biomedical effects under in vivo conditions, infected wounds were induced and inoculated with Staphylococcus aureus (ATCC 25923), and Pseudomonas aeruginosa (ATCC 27853). The results indicated spherical ZnO nanoparticles on the surface of malachite and strong antibacterial activity and antioxidant properties. The ointments produced from the nanocomposites also exhibited wound healing activity. The administration of the ointments prepared from ZnO/Mlt, and ZnO/Mlt/Chsn NCs decreased the expressions of IL-1β, IL-6, and TNF-α, while it increased the expressions of IL-10, TGF-β and bFGF. In sum, the nanocomposites produced from ZnO, malachite, and chitosan had better biological activity than ZnO/Malachite nanocomposites. We suggest applying ZnO/Mlt/Chsn nanocomposites in the structure of ointments to treat infected wounds after future clinical studies., (© 2022. The Author(s).)

Several types of cheeses including white brined cheese have been linked to listeriosis outbreaks worldwide. This study aimed to (i) investigate the in vitro inhibitory activity of zinc oxide (ZnO) nanoparticles (NPs) at concentrations of 0.0125-0.1% against three Listeria monocytogenes strains at 10 or 37°C, (ii) evaluate the antimicrobial efficiency of chitosan-based coating containing 1.0% ZnO NPs against L. monocytogenes on the surface or inside vacuum-packaged white brined cheese at 4 or 10°C, and iii) determine the migration of ZnO NPs from the surface to the interior of cheeses using energy dispersive X-ray analysis (EDX). The antimicrobial activity of ZnO NPs was higher at 37°C than at 10°C. The initial numbers (4.0 log CFU/ml) of two L. monocytogenes strains were reduced below detectable levels, while the third strain was reduced by 1.2 log CFU/ml at 37°C. At 10°C, the initial L. monocytogenes numbers were reduced by 0.4-1.9 log CFU/ml. Chitosan coating containing 1.0% ZnO NPs reduced L. monocytogenes numbers by 1.5 and 3.7 log CFU/g on the surface or by 0.9 and 1.5 log CFU/g in the interior of vacuum-packed cheese stored at 10 or 4°C, respectively. The EDX results showed that ZnO NP levels remained constant on the cheese surface with no indication of migration into the cheese matrix at the end of storage. Practical Application: Chitosan and ZnO are antimicrobial agents and their combination in edible coatings has the potential for inactivating foodborne pathogens. Chitosan coating containing ZnO NPs can be used as an effective active packaging material to reduce numbers of L. monocytogenes in white brined cheese., (© 2022 Institute of Food Technologists®.)

In this study we aimed to develop novel ZnO-NP/chitosan/β-glycerophosphate (ZnO-NP/CS/β-GP) antibacterial hydrogels for biomedical applications. According to the mass fraction ratio of ZnO-NPs to chitosan, mixtures of 1, 3, and 5% ZnO-NPs/CS/β-GP were prepared. Using the test-tube inversion method, scanning electron microscopy and Fourier-transform infrared spectroscopy, the influence of ZnO-NPs on gelation time, chemical composition, and cross-sectional microstructures were evaluated. Adding ZnO-NPs significantly improved the hydrogel's antibacterial activity as determined by bacteriostatic zone and colony counting. The hydrogel's bacteriostatic mechanism was investigated using live/dead fluorescent staining and scanning electron microscopy. In addition, crystal violet staining and MTT assay demonstrated that ZnO-NPs/CS/β-GP exhibited good antibacterial activity in inhibiting the formation of biofilms and eradicating existing biofilms. CCK-8 and live/dead cell staining methods revealed that the cell viability of gingival fibroblasts (L929) cocultured with hydrogel in each group was above 90% after 24, 48, and 72 h. These results suggest that ZnO-NPs improve the temperature sensitivity and bacteriostatic performance of chitosan/β-glycerophosphate (CS/β-GP), which could be injected into the periodontal pocket in solution form and quickly transformed into hydrogel adhesion on the gingiva, allowing for a straightforward and convenient procedure. In conclusion, ZnO-NP/CS/β-GP thermosensitive hydrogels could be expected to be utilized as adjuvant drugs for clinical prevention and treatment of peri-implant inflammation.

Endophytic bacteria with multi-trait plant beneficial features have applications to enhance agricultural productivity by supporting the plant growth, yield, and disease resistance. In this study, Paenibacillus sp. CCB36 was isolated from the rhizome of Curcuma caesia Roxb., and its biofilm formation and antifungal properties have been evaluated in the presence of nanoparticles. Chitosan nanoparticles (CNPs) were synthesized and characterized by UV-visible spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, high-resolution-transmission electron microscopic (HR-TEM) analysis, scanning electron microscopic (SEM) analysis, and dynamic light scattering (DLS). The effect of zinc oxide nanoparticles (ZnONPs) and CNPs on biofilm formation of Paenibacillus sp. CCB36 was evaluated by tissue culture plate assay. ZnONPs reduced its biofilm formation and was found to get modulated in the presence of CNPs as revealed by atomic force microscopy (AFM). Hence, CNPs were selected for further studies. Interestingly, biocontrol property of Paenibacillus sp. CCB36 against Rhizoctonia solani was also found to get enhanced when supplemented with chitosan nanoparticles. The results of the study indicate application of nanoparticles to improve colonization and active functioning of endophytic bacteria which can have significant application in agriculture., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Utilization of biomolecules encapsulated nano particles is currently originating ample attention to generate unconventional nanomedicines in antiviral research. Zinc oxide nanoparticle has been extensively studied for antimicrobial, antifungal and antifouling properties due to high surface to volume ratios and distinctive chemical as well as physical properties. Nevertheless, still minute information is available on their response on viruses. Here, in situ nanostructured and polysaccharide encapsulated ZnO NPs are fabricated with having antiviral potency and low cytotoxicity (%viability ~ 90%) by simply controlling the formation within interspatial 3D networks of hydrogels through perfect locking mechanism. The two composites ChH@ZnO and ChB@ZnO shows exceedingly effective antiviral activity toward Human cytomegalovirus (HCMV) having cell viability 93.6% and 92.4% up to 400 μg mL -1 concentration. This study brings significant insights regarding the role of ZnO NPs surface coatings on their nanotoxicity and antiviral action and could potentially guide to the development of better antiviral drug., (Copyright © 2021. Published by Elsevier Ltd.)

In this study, cotton fabrics based on zinc oxide nanoparticles in situ synthesis, acyclovir, nanochitosan, and clove oil were treated. The treated cotton fabrics were examined by FTIR, HR-TEM, FE-SEM, EDAX, and the surface roughness processing of FE-SEM images. The obtained characterization data emphasized the nano-size of nanocomposite with high homogeneity of particles in spherical shape as well as affirmed the deposition of nanocomposite onto the textile fibers with concluded that the deposition of nanocomposite was increased parallel with sonication time. Antimicrobial and antiviral activities of treated cotton fabrics were evaluated. Results revealed that treated cotton fabrics exhibited promising antibacterial activity toward Gram-positive higher than Gram-negative bacteria. Likewise, treated cotton fabrics are still effective as antibacterial after washing for 100 cycles. Moreover, treated cotton fabrics exhibited potential antifungal activity against Candida albicans, Aspergillus niger, and Aspergillus fumigatus. The antiviral activity significantly depended on the type of virus. The treated cotton fabrics showed antiviral activity against tested viral particles (HSV-1, Adeno, and CoxB2) with viral inhibition of 95.9, 76.4, and 86.9% respectively, while in the case of coated cotton textile with acyclovir, it only exhibited viral inhibition of 49.9, 41, and 22.3% respectively., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

In this present work, a new design for antimicrobial wound bandages is presented. The wound dressings were prepared using cotton fibers reinforced with elastic compression straps and secured with a polyester fabric of tight mesh size. The cotton pads were doped with a wound healing biocomposite, composed of chitosan, glycogen, and ZnO nanoparticles (CG@ZnONPs) previously formulated through a green process. The size of ZnONPs in the prepared CG@ZnONPs was 30-80 nm. The cotton pads impregnated with the CG@ZnONPs nanocomposite were characterized using FTIR, SEM, EDX, TGA, and DTGA methods. Moreover, the prepared dressings were tested on a number of intentionally injured rats. In this experiment, the % contraction of the treated wounds was monitored and compared to that of a control group of wounded rats, to which only sterile gauzes were applied. The results showed a much faster and an almost complete healing of rats treated with the synthesized dressings and the results were further confirmed by histopathological examination. The dressings were also found to exert a significant antimicrobial activity against a number of pathogenic microorganisms, generally encountered in common wounds, and could therefore be recommended to be a novel biomedical application for a fast, successful, and flawless wounds healing process., (Copyright © 2021 Elsevier B.V. All rights reserved.)

In this research, bioactive nano-hybrids based on the nano-fibrillar chitosan-ZnO (NF-CS-ZnO) were synthesized to diminish the toxicity of ZnO-NPs. The successful formation of nano-hybrids was confirmed by FT-IR, UV-Vis, and FE-SEM analyses, showing a uniform spherical ZnO-NPs with an average diameter of 20-30 nm, homogeneously dispersed on NF-CS. The obtained results demonstrated a remarkable antibacterial activity of NF-CS-ZnO-0.6 nano-hybrid against E. coli and S. aureus and, interestingly, no cytotoxic on normal cells (even at a high concentration of 100 μg/mL). Furthermore, NF-CS hybridization efficiently decreased the up-regulation in Cas3, Cas9, and Il6 of inspected fishes compared to the ZnO-NPs. Histopathological examination revealed hepatocyte necrosis in the fish exposed to ZnO-NPs and hyperemia exposed to NF-CS-ZnO-0.6 nano-hybrid. Finally, NF-CS efficiently improved the bio-safety and bactericidal activity of ZnO-NPs; therefore, NF-CS-ZnO nano-hybrid is prominently recommended as a talented low-toxicity antibacterial agent replacement of conventional ZnO-NPs for use in different applications., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Biocidal activity and biocompatibility of nanomaterials (NMs) are crucial for healthcare applications. This study aims to develop biocidal hybrid NMs with high inhibition rates to control multidrug-resistant bacterial infection compared to conventional antibiotics. Herein, ZnO, chitosan-ZnO (CZnO) and alginate-ZnO (AZnO) NMs were synthesized via a simple one-pot technique. The one-pot process facilitates the efficiency of a chemical reaction whereby a reactant is subjected to successive chemical reactions in just one step. The resulted NMs bio-physicochemical features were analyzed using various analytical methods. The bactericidal and bacteriostatic mechanism of NMs strongly depends on the production of reactive oxygen species in NMs, due to their size, large surface areas, oxygen vacancies, ion release, and diffusion ability. The antibacterial potential of the NMs was tested against methicillin-resistant Staphylococcus aureus. The inhibition zone disclosed that the AZnO possessed an excellent antibacterial activity compared to ZnO and CZnO. Furthermore, toxicity studies revealed that the AZnO demonstrated low toxicity to the HepG2 cell lines. These results confirmed that the AZnO hybrid nanomaterials are promising futuristic biocidal agents suitable for the clinical and healthcare industries., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In this paper, designing electrospun composite nanofibers containing poly (lactic acid) (PLA) and keratin/poly (vinyl alcohol) (K/PVA) as the major components and natural nanofibrillated chitosan (CHNF)/ZnO nanoparticles (ZnONPs) (CSZ) combination as the nanofiller ingredient, has been investigated. PLA solution from one syringe and K/PVA from another one with incorporation of CHNF (CS), CSZ (2:1), (1:1) and (1:2) were electrospun and produced nanofibers were formed on the rotating collector. Addition of CHNF and ZnONPs amounts in CSZ combination resulted in reduction of the diameter of nanofibers. The highest hydrophilicity was reported for K/PVA/CS-PLA/CS sample with the contact angle of about 43 ± 3°. AFM results for K/PVA-PLA, K/PVA/CS-PLA/CS and K/PVA/CSZ(2:1)-PLA/CSZ(2:1), K/PVA/CSZ(1:2)-PLA/CSZ(1:2) samples indicated that the surface roughness factor for these nanofibers was about 708, 277, 378 and 658 nm, respectively. DSC analysis for K/PVA/CSZ(1:2)-PLA/CSZ(1:2) structure exhibited that the peaks related to the melting points of PLA and PVA shifted to higher temperatures. Overally, K/PVA/CSZ(2:1)-PLA/CSZ(2:1) nanofiber with diameter of 352.50 ± 31 nm, contact angle of 48 ± 3°, tensile strength of 0.96 ± 0.18 MPa is suggested as a proper wound healing scaffold that has highest antibacterial as well as potential to increase cell proliferation., (Copyright © 2021. Published by Elsevier B.V.)

Cell density-based intercellular signaling mechanism is known as Quorum sensing (QS); it serves a significant role in regulating the pathogenic factors. The objective of the present study was to assess the influence of chitosan-zinc oxide nanocomposite (CH-ZnO nanocomposite), alone and in combination with gentamicin, on the sensitivity to hydrogen peroxide (H 2 O 2 ), the production of pathogenic factors and QS-regulated genes of Pseudomonas aeruginosa. The efficacy of the minimum inhibitory concentration (MIC) and 1/4 MIC of the CH-ZnO nanocomposite, alone and in combination with gentamicin, on the sensitivity to H 2 O 2 , pyocyanin secretion, swarming and twitching motilities was evaluated. In addition, the expression of some QS-regulated genes including rhlI, rhlR, lasI and lasR genes was measured by Real-time quantitative PCR (RT-qPCR) following exposure to the nanocomposite. The results demonstrated that at MIC concentrations, the gentamicin-loaded CH-ZnO nanocomposite significantly inhibited QS-regulated phenotypes such as pyocyanin secretion (82.4%), swarming (76%) and twitching (73.6%) motilities; further it increased the inhibition growth zone (134.5%), as well as, at 1/4 MIC concentration decreased the expression of lasI (72%), lasR (78%), rhlI (76%) and rhlR (82%) genes; as compared to untreated P. aeruginosa PAO1 (P < 0.05). Our results also demonstrated that the CH-ZnO nanocomposite combined with gentamicin could be a potential innovative candidate, which could be broadly applied in the treatment of P. aeruginosa infections., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

This research work was performed to prepare chitosan-alginate-gelatin and chitosan-bentonite-gelatin films in different mass ratios incorporated with nano particles of Zinc Oxide, which were achieved through the method of green synthesis from Nettle leaf extract. The films were prepared and characterized based on their physicochemical properties, such as water absorption and porosity and surface morphology. Bentonite containing films illustrate more flexibility than alginate ones while the chitosan/bentonite composite films have a maximum water absorption capacity of about 170%. The antibacterial activity of the films was investigated against Staphylococcus aureus and Pseudomonas aeruginosa bacteria and it presents good inhibitory activities against the tested bacteria as compared to the control sample. Furthermore, vivo animal tests were performed to confirm the applicability of the prepared films as a healing material for burned skin. Skin appendages, such as hair follicles and sebaceous gland in the dermis, were detected in normal structures by applying both of the composites to damaged skin. In the control sample (gauze), no re-epithelialized area was observed, except in close proximity of the wound border. The results show that due to its full coverage of the wounds with new epithelium and hair follicles, bentonite-containing composites are more preferred., (Copyright © 2021 Elsevier B.V. All rights reserved.)