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Zein is a biodegradable and biocompatible material extracted from renewable resources; it comprises almost 80% of the whole protein content in corn. This review highlights and describes some zein and zein-based materials, focusing on biomedical applications. It was demonstrated in this review that the biodegradation and biocompatibility of zein are key parameters for its uses in the food-packing, biomedical and pharmaceutical fields. Furthermore, it was pointed out that the presence of hydrophilic-hydrophobic groups in zein chains is a very important aspect for obtaining material with different hydrophobicities by mixing with other moieties (polymeric or not), but also for obtaining derivatives with different properties. The physical and chemical characteristics and special structure (at the molecular, nano and micro scales) make zein molecules inherently superior to many other polymers from natural sources and synthetic ones. The film-forming property of zein and zein-based materials is important for several applications. The good electrospinnability of zein is important for producing zein and zein-based nanofibers for applications in tissue engineering and drug delivery. The use of zein's hydrolysate peptides for reducing blood pressure is another important issue related to the application of derivatives of zein in the biomedical field. It is pointed out that the biodegradability and biocompatibility of zein and other inherent properties associated with zein's structure allow a myriad of applications of such materials with great potential in the near future. [ABSTRACT FROM AUTHOR]

Chitosan, which is derived from a deacetylation reaction of chitin, has attractive antimicrobial activity. However, chitosan applications as a biocide are only effective in acidic medium due to its low solubility in neutral and basic conditions. Also, the positive charges carried by the protonated amine groups of chitosan (in acidic conditions) that are the driving force for its solubilization are also associated with its antimicrobial activity. Therefore, chemical modifications of chitosan are required to enhance its solubility and broaden the spectrum of its applications, including as biocide. Quaternization on the nitrogen atom of chitosan is the most used route to render water-soluble chitosan-derivatives, especially at physiological pH conditions. Recent reports in the literature demonstrate that such chitosan-derivatives present excellent antimicrobial activity due to permanent positive charge on nitrogen atoms side-bonded to the polymer backbone. This review presents some relevant work regarding the use of quaternized chitosan-derivatives obtained by different synthetic paths in applications as antimicrobial agents. [ABSTRACT FROM AUTHOR]

ABSTRACT The development of superabsorbent hydrogels (SHs) is a very important issue in both academic and industrial fields because of their applications in several technologies. The impressive number of publications dealing with SH confirms this statement: a quick search in the ISI (Web of Science) database under the words superabsorbent hydrogels revealed more than 600 articles published, with about 80% of those published in last decade. Current studies on the development of SHs have focused on the formulation of highly functional materials with enhanced properties for suitable applications in different fields. In light of this, the incorporation of microsized or nanosized materials in SH formulations has been explored as a very attractive strategy for tailoring desired properties. In this review, we discuss relevant aspects of the current knowledge of SHs and nanocomposite polymer hydrogels, mainly those based on chitin and cellulose nanocrystals (fibers and/or whiskers), bringing to light some structure-property relationships and future trends. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39725. [ABSTRACT FROM AUTHOR]

N-Trimethyl chitosan (TMC), an antibacterialagent,and heparin (HP), an antiadhesive biopolymer, were alternately depositedon modified polystyrene films, as substrates, to built antiadhesiveand antibacterial multilayer films. The properties of the multilayerfilms were investigated by Fourier transform infrared spectroscopy,atomic force microscopy, scanning electron microscopy, and Kelvinforce microscopy. In vitro studies of controlled release of HP wereevaluated in simulated intestinal fluid and simulated gastric fluid.The initial adhesion test of E. colion multilayer films surface showed effective antiadhesive properties.The in vitro antibacterial test indicated that the multilayer filmsof TMC/HP based on TMC80 can kill the E. colibacteria. Therefore, antiadhesive and antibacterial multilayer filmsmay have good potential for coatings and surface modification of biomedicalapplications. [ABSTRACT FROM AUTHOR]

Background: The ever-growing number of infections caused by multidrug-resistant (MDR) bacterial strains requires an increased effort to develop new antibiotics. Herein, we demonstrate that a new class of gold nanoparticles (Au NPs), defined by shape and conjugated with ceragenin CSA-131 (cationic steroid antimicrobial), display strong bactericidal activity against intractable superbugs. Methods: For the purpose of research, we developed nanosystems with rod- (AuR NPs@CSA-131), peanut-(AuP NPs@CSA-131) and star-shaped (AuS NPs@CSA-131) metal cores. Those nanosystems were evaluated against bacterial strains representing various groups of MDR (multidrug-resistant) Gram-positive (MRSA, MRSE, and MLSb) and Gram-negative (ESBL, AmpC, and CR) pathogens. Assessment of MICs (minimum inhibitory concentrations)/MBCs (minimum bactericidal concentrations) and killing assays were performed as a measure of their antibacterial activity. In addition to a comprehensive analysis of bacterial responses involving the generation of ROS (reactive oxygen species), plasma membrane permeabilization and depolarization, as well as the release of protein content, were performed to investigate the molecular mechanisms of action of the nanosystems. Finally, their hemocompatibility was assessed by a hemolysis assay. Results: All of the tested nanosystems exerted potent bactericidal activity in a manner resulting in the generation of ROS, followed by damage of the bacterial membranes and the leakage of intracellular content. Notably, the killing action occurred with all of the bacterial strains evaluated, including those known to be drug resistant, and at concentrations that did not impact the growth of host cells. Conclusions: Conjugation of CSA-131 with Au NPs by covalent bond between the COOH group from MHDA and NH3 from CSA-131 potentiates the antimicrobial activity of this ceragenin if compared to its action alone. Results validate the development of AuR NPs@CSA-131, AuP NPs@CSA-131, and AuS NPs@CSA-131 as potential novel nanoantibiotics that might effectively eradicate MDR bacteria. [ABSTRACT FROM AUTHOR]

Wound infections are one of the major reasons for the delay in the healing of chronic wounds and can be overcome by developing effective wound dressings capable of absorbing exudate, providing local antibiotic release, and improving patient comfort. Arabinoxylan (AX) is a major hemicellulose present in psyllium seed husk (PSH) and exhibits promising characteristics for developing film dressings. Herein, AX-gelatin (GL) films were prepared by blending AX, gelatin (GL), glycerol, and gentamicin (antibiotic). Initially, the optimal quantities of AX, GL, and glycerol for preparing transparent, bubble-free, smooth, and foldable AX-GL films were found. Physiochemical, thermal, morphological, drug release, and antibacterial characteristics of the AX-GL films were evaluated to investigate their suitability as wound dressings. The findings suggested that the mechanical, water vapor transmission, morphological, and expansion characteristics of the optimized AX-GL films were within the required range for wound dressing. The results of Fourier-transform infrared (FTIR) analyses suggested chemical compatibility among the ingredients of the films. In in vitro drug release and antibacterial activity experiments, gentamicin (GM)-loaded AX-GL films released approximately 89% of the GM in 24 h and exhibited better antibacterial activity than standard GM solution. These results suggest that AX-GL films could serve as a promising dressing to protect against wound infections. [ABSTRACT FROM AUTHOR]

Renewable material packs have been an alternative to traditional petroleum-based products. Thus, this work aimed to develop an active and biodegradable coating based on κ-carrageenan/starch containing copper oxide particles (CuOPs) for fresh pears. The composite material was extensively characterized. Digital images of the coatings suggested stable and highly transparent materials. The composites presented handleability and flexibility. However, only the κ75 films prepared at 75:25 κ-carrageenan/starch weight ratio containing 0, 1, 1.5, and 2% (wt/wt) of CuOPs concerning the polysaccharide content demonstrated applicability as surface coatings for fresh pears. The water vapor permeation, tensile strength, and elongation at the break ranged from 1.14 × 10−10 to 1.59 × 10−10 Pa⋅m2·s−1, 26.19–101.67 MPa, and 6.73 to 17.05 wt%, respectively. Micrographs showed composite films with slight roughness and homogenous surfaces exhibiting hydrophilic characteristics supported by water contact angle measurements (between 71 and 84°). The films were durable for approximately 90 min in an aqueous solution, with the ability to expand their mass up to 3847% (sample κ75-0). The materials were tested as coatings on fresh pears under consumption conditions. The film κ75-2 conserved the fruit for consumption over 30 days, supporting better results than the commercial poly (vinyl chloride) pack. The composite material based on κ-carrageenan/starch containing CuOPs, especially the κ75-2 composite at 2.0% (wt/wt) of CuOPs, can be applied as a surface coating for fresh pears. • Biodegradable coatings were produced from commercial polysaccharides. • The formulations resulted in transparent, easy to handle, flexible, and non-cracking materials. • CuONPs enhanced coatings in mechanical properties and UV barrier efficiency. • Coated fruits maintained quality even after 30 days of storage. • The novel-produced material has potential application as a coating on fresh fruit. [ABSTRACT FROM AUTHOR]

Patients in hospital environments are susceptible to bacterial colonization, which can lead to infections. In this study, electrospun fibers were manufactured using poly(vinyl alcohol) (PVA) crosslinked with citric acid (CA) and incorporating the ionic liquid (IL) 1-hexadecyl-3-methylimidazolium chloride (C 16 MImCl) to prevent microbial growth and biofilm formation. The presence of CA and IL reduced the surface tension of the PVA solution (12% w/v) from 52.07 mN/m to 35.84 mN/m. CA was introduced into PVA solutions, and the resulting fibers were thermally crosslinked through esterification between PVA hydroxyl groups and CA. X-ray photoelectron spectroscopy (XPS) confirmed the presence of IL on the fiber surfaces. The IL acted as a surfactant, imparting plasticity to the electrospun fibers and enhancing homogeneity and mechanical properties. Before crosslinking, the PVA/CA/IL fibers exhibited an elongation at break (%) of approximately 140%, a tensile strength of 5.3 MPa, and an elastic modulus of 18.2 MPa. After cross-linking, the elongation at break reduced to 86%, the tensile strength increased to 7.6 MPa, and the elastic modulus increased to 88 MPa. Mechanical measurements confirmed the thermal crosslinking of the fibers, primarily because of the increased elastic modulus. Adhesion and proliferation tests with Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) indicated reduced bacterial adhesion and growth on the PVA/CA/IL fibers. Antimicrobial assays further confirmed a 50.73% and 69.42% increase in bactericidal activity against S. aureus and P. aeruginosa , respectively. The PVA/CA/IL fibers exhibit promising potential for producing antimicrobial materials to prevent the attachment and proliferation of microbial strains on solid surfaces. • The ionic liquid 1-hexadecyl-3-methylimidazolium was electrospuned with poly(vinyl alcohol)/citric acid. • The ionic liquid improved the electrospinnability of the polymer solutions. • The fibers were thermally cross-linked through esterification reaction. • The fibers containing the ionic liquid promoted anti-adhesive and antimicrobial properties. [ABSTRACT FROM AUTHOR]

• Chondroitin sulfate and gelatin surface coatings were assembled in water. • The surface coatings were associated with ionic liquids on poly(ethylene terephthalate). • The surface coatings prevented the ionic liquid cytotoxic effect on fibroblast cells. • The surface coatings containing an ionic liquid supported virucidal activity against the mouse hepatitis virus. The cytotoxicity of ionic liquids (ILs) in solution, including aqueous 1-n-hexadecyl-3-methylimidazolium chloride (C 16 MImCl), 1-n-hexadecyl-3-methylimidazolium methane sulfonate (C 16 MImMeS), and 1-n-hexadecyl pyridinium chloride monohydrate (C 16 PyrCl⋅H 2 O) solutions and polyelectrolyte multilayers (PEMs) containing ILs were investigated against mouse hepatitis virus (MHV-3) and fibroblast cells (L929). C 16 MImMeS and C 16 PyrCl⋅H 2 O exhibited virucidal activity against MHV-3 after 30 s of exposure at 662.31 nM and 744.88 nM, respectively. However, these ILs demonstrated considerable toxicity against fibroblast cells (2.0 × 105 cells/well) at 583 nM (C 16 MImCl), 498 nM (C 16 MImMeS), and 559 nM (C 16 PyrCl⋅H 2 O), limiting their direct application in aqueous solutions. Therefore, these ILs were combined with PEMs consisting of alternating 15 layers of gelatin (GE) and chondroitin sulfate (CS) to address this limitation. The PEMs were deposited on oxidized poly(ethylene terephthalate) (PET) using the layer-by-layer (LbL) approach. The ILs altered the relative surface adhesion force, reducing it from 4.08 nN on GE/CS PEM to the range between 2.23 and 3.10 nN on the GE/CS IL PEMs. The ILs enhanced surface electrostatic forces while decreasing adhesion forces on the surfaces. Incorporating ILs into the PEMs proved a promising strategy as they reduced the toxicity of the ILs towards L929 cells while maintaining their virucidal efficacy. The GE/CS PEM without IL did not exhibit virucidal activity against MHV-3. In contrast, GE/CS PEMs combined with C 16 MImMeS showed virucidal activity after 24 h, inactivating 99.99 % of the virus. The PEMs associated with the ILs were cytocompatible toward the L929 cells after a 48-hour incubation period. GE/CS IL PEMs hold promise as cytocompatible surface coatings for solid materials due to their durability and ability to prevent viral growth. [ABSTRACT FROM AUTHOR]

Environmental pollution caused by non-biodegradable plastic pollutants adversely affects various ecosystems. This study proposes the development of novel functional and biodegradable films based on corn starch (CST) and pectin (PEC) containing zinc oxide nanoparticles (ZnONPs) from the casting method. The films exhibited processability, transparency, low water vapor permeation, and desirable mechanical properties for food packaging and coating applications. The ZnONPs acted as a plasticizer, enhancing the film elongation at the break, increasing the pec25-1 (PEC 25 wt% and ZnONPs 1 wt%) elongation from 79.85 to 162.32 %. The improved film elasticity supported by ZnONPs reduced the material stiffness. However, the films still demonstrated an average tensile strength (0.69 MPa) 17-fold higher than the tensile strength (0.04 MPa) of the non-biodegradable commercial film based on poly(vinyl chloride). Furthermore, the ZnONPs enhanced the UV-blocking capabilities of the films, leading to wettable materials with water contact angles lower than 90°. The films showed high biodegradation rates under natural disposal conditions. The results indicated that the pec25-1/ZnONPs film is a promising eco-friendly coating in food preservation due to its biodegradability, suitable mechanical properties, low water vapor permeability, and UV-blocking properties. • Biodegradable films based on PEC/CST/ZnONPs were produced using the casting method. • The ZnONPs increased the elasticity of all the materials, especially pec25-1 (162 %). • The average tensile strength is seventeen times higher than commercial films. • The biodegradability test indicates a mass loss of nearly 40 % for all formulations. • Low-WVP, improved mechanical and biodegradable properties point to promising material [ABSTRACT FROM AUTHOR]

Given the environmental issues caused by the extensive use of conventional petroleum-based packaging, this work proposes functional films based on commercial κ-carrageenan (κc), poly(vinyl alcohol) (PVA), and gallic acid (GA) prepared by the "casting" method. Metallic ions in the κc composition stabilized the films, supporting processability and suitable mechanical properties. Howe v er, the incorporated GA amount (6.25 and 10 wt%) in the films created from an aqueous κc solution at 3.0 % wt/v (κc3) prevented crystalline domains in the resulting materials. The κc3/GA6.25 and κc3/GA10 films had less tensile strength (8.50 ± 0.61 and 10.28 ± 0.65 MPa) and high elongation at break (2.36 ± 0.16 and 1.19 ± 0.17 %) compared to the other samples, respectively. Low κc contents (κc2.5/GA6.25 and κc2.5/GA10) promoted stiff films and less permeability to water vapor (5.36 ± 0.51 and 3.76 ± 0.02 [×10−12 g(Pa × m × s)−1], respectively. The κc/GA weight ratio also influenced the film wettability, indicating water contact angles (WCAs) between 55 and 74°. The surface wettability implies a low oil permeability and high water swelling capacity of up to 1600 %. The κc/GA also played an essential role in the film's antimicrobial action against Staphylococcus aureus and Escherichia coli. Thus, the κc3/GA10 film showed suitable physical, chemical, and biological properties, having the potential to be applied as food coatings. [ABSTRACT FROM AUTHOR]

• Surface coatings were engineered to treat bacterial corn streak disease. • The surface coatings protect the corn leaves from bacterial infection. • The surface coating reduces the synthon of bacterial corn streak dissemination. • A commercial ionic liquid has in vitro but not in vivo antimicrobial activity. • The filming-forming property of polymers is essential to protect the corn leaves. The bacterial corn streak disease, caused by Xanthomonas vasicola pv. vasculorum (Xvv) has emerged as a threat to corn production due to its rapid spread and resistance to conventional agrochemicals. Therefore, this study proposes polymeric surface coatings based on chitosan (CS) and tannins (TN) as antimicrobial agents against Xvv. The coatings were formed via the layer-by-layer (LbL) approach on oxidized polystyrene (PS). The coatings increased the wettability and roughness of the surfaces. In vitro assays measuring the minimum inhibitory and minimum bactericidal concentrations (MIC and MBC) demonstrated the antimicrobial activity of CS and TN. Coatings deposited on PS exhibited in vitro anti-adhesive properties against Xvv. The in vitro antimicrobial results were compared with control assays performed with an ionic liquid (IL). The IL was also associated with the polymeric coatings. Polymeric coatings, with or without IL, were deposited on corn leaves for in vivo assays. The IL had no activity against Xvv , and its presence in the CS solution seemed to impair the coating deposition on the corn leaves. However, the in vivo assays confirmed the protective efficacy of the polymeric coatings against Xvv infection, acting as physical barriers. The surface coatings also significantly reduced the Xvv symptoms in infected plants even after the disease spread. These outcomes were attributed to the film-forming ability of CS and TN polymers, the coatings' antimicrobial action, and the LbL efficiency in depositing the coatings on the corn leaves. This study introduces a promising environmentally and economically viable strategy for combating bacterial corn streak disease using biodegradable, cytocompatible natural polymers. The surface coatings offer a sustainable method to address bacterial corn disease, overcoming the limitations of agrochemicals. [ABSTRACT FROM AUTHOR]

Polyelectrolyte multilayers (PEMs) based on hyaluronic acid (HA) and poly (diallyldimethylammonium chloride) (PDDA) were deposited on oxidized polystyrene (PS ox ) via the layer-by-layer (LbL) method. The X-ray photoelectron spectroscopy (XPS) confirmed the PEM deposition on PS ox , and atomic force microscopy (AFM) indicated that the surface roughness of PS also increased after PEM deposition. The PEMs significantly enhanced PS wettability, reducing the contact angle from 73° on PS to 24° on PDDA-terminated (PDDA/HA) 2.5 PEM (2.5 bilayers, 5 layers) and 36° on HA-terminated (PDDA/HA) 3 PEM (3 bilayers, 6 layers). The HA-terminated (PDDA/HA)₃ PEM demonstrated antimicrobial activity. Compared to uncoated PS surfaces, this PEM reduced the surface coverage of viable P. aeruginosa cells from 36.5 % to 3.7 % and S. aureus cells from 13.3 % to 2.5 % on uncoated PS surfaces. The antimicrobial assay following the JIS Z 2801-2010 standard demonstrated that the PDDA-terminated (PDDA/HA) 2.5 PEM inhibited S. aureus growth by 48 %, compared to 32 % inhibition by the HA-terminated (PDDA/HA) 3 PEM relative to the uncoated and non-oxidized polystyrene (PS) surface (control). HA-terminated PEM demonstrated lesser antimicrobial activity than PDDA-terminated PEM. However, both PEMs were cytocompatible against erythrocytes and human adipose-derived stem cells (ADSCs), indicating their potential for biomedical applications, particularly prosthetic coatings., Competing Interests: Declaration of competing interest The authors declare no competing financial interests or personal relationships that could have influenced the findings presented in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper.

HER2 antigen is a marker used for breast cancer diagnosis and prevention. Its determination has great importance since breast cancer is one of the most insidious types of cancer in women. HER2 antigen assessment in human serum is traditionally achieved by enzyme-linked immunosorbent assay (ELISA method), but it has some disadvantages, such as suppressing the thermodynamic-kinetic studies regarding the antibody-antigen interaction, and the use of labeled molecules that can promote false positive responses. Biosensors based on surface plasmon resonance (SPR) are sensitive optical techniques widely applied on bioassays. The plasmonic devices do not operate with labeled molecules, overcoming conventional immunoassay limitations, and enabling a direct detection of target analytes. In this way, a new SPR biosensor to assess HER2 antigen has been proposed, using nanohole arrays on a gold thin film by signal transduction of transmitted light measurements from array image acquisitions. These metallic nanostructures may couple the light directly on surface plasmons using a simple collinear arrangement. The proposed device reached an average sensitivity for refractive index (RI) variation on a metal surface of 4146 intensity units/RIU (RIU = RI units). The device feasibility on biomolecular assessment was evaluated. For this, 3 ng ml -1 known HER2 antigen concentration was efficiently flowed (using a microfluidic system) and detected from aqueous solutions. This outcome shows that the device may be a powerful apparatus for bioassays, particularly toward breast cancer diagnosis and prognosis.