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Biodegradable polymer-based nanocomposite coatings provide multiple advantages to modulate the corrosion resistance and cytocompatibility of magnesium (Mg) alloys for biomedical applications. Biodegradable poly(glycerol sebacate) (PGS) is a promising candidate used for medical implant applications. In this study, we synthesized a new PGS nanocomposite system consisting of hydroxyapatite (HA) and magnesium oxide (MgO) nanoparticles and developed a spray coating process to produce the PGS nanocomposite layer on pretreated Mg substrates, which improved the coating adhesion at the interface and their cytocompatibility with bone marrow derived mesenchymal stem cells (BMSCs). Prior to the spray coating process of polymer-based nanocomposites, the Mg substrates were pretreated in alkaline solutions to enhance the interfacial adhesion strength of the polymer-based nanocomposite coatings. The addition of HA and MgO nanoparticles (nHA and nMgO) to the PGS matrix, as well as the alkaline pretreatment of the Mg substrates, significantly enhanced the interfacial adhesion strength when compared with the PGS coating on the nontreated Mg control. The average BMSC adhesion densities were higher on the PGS/nHA/nMgO coated Mg than the noncoated Mg controls under direct contact conditions. Moreover, the addition of nHA and nMgO to the PGS matrix and coating the nanocomposite onto Mg substrates increased the average BMSC adhesion density when compared with the PGS/nHA/nMgO coated titanium (Ti) and PGS coated Mg controls under direct contact. Therefore, the spray coating process of PGS/nHA/nMgO nanocomposites on Mg substrates or other biodegradable metal substrates could provide a promising surface treatment strategy for biodegradable implant applications.

Diamond-like Carbon (DLC) has been used as a coating material of choice for a variety of technological applications owing to its favorable bio-tribo-thermo-mechanical characteristics. Here, the possibility of bringing DLC into orthopedic joint implants is examined. With ever increasing number of patients suffering from osteoarthritis as well as with the ingress of the osteoarthritic joints malaise into younger and more active demographics, there is a pressing need to augment the performance and integrity of conventional total joint replacements (TJRs). Contemporary joint replacement devices use metal-on-polymer articulations to restore function to worn, damaged or diseased cartilage. The wear of polymeric components has been addressed using crosslinking and antioxidants; however, in the context of the metallic components, complications pertaining to corrosion and metal ion release inside the body still persist. Through this review article, we explore the use of DLC coatings on metallic bearing surfaces and elucidate why this technology might be a viable solution for ongoing electrochemical challenges in orthopedics. The different characteristics of DLC coatings and their feasibility in TJRs are examined through assessment of tribo-material characterization methods. A holistic characterization of the coating-substrate interface and the wear performance of such systems are discussed. As with all biomaterials used in TJRs, we need mindful consideration of potential in-vivo challenges. We present a few caveats for DLC coatings including delamination, hydrophobicity, and other conflicting as well as outdating findings in the literature. We recommend prudently exploring DLC films as potential coatings on metallic TJR components to solve the problems pertaining to wear, metal ion release, and corrosion. Ultimately, we advise bringing DLC into clinical use only after addressing all challenges and concerns outlined in this article.

The evolution of endovascular therapies, particularly in the field of intracranial aneurysm treatment, has been truly remarkable and is characterized by the development of various stents. However, ischemic complications related to thrombosis or downstream emboli pose a challenge for the broader clinical application of such stents. Despite advancements in surface modification technologies, an ideal coating that fulfills all the desired requirements, including anti-thrombogenicity and swift endothelialization, has not been available. To address these issues, we investigated a new coating comprising 3-aminopropyltriethoxysilane (APTES) with both anti-thrombogenic and cell-adhesion properties. We assessed the anti-thrombogenic property of the coating using an in vitro blood loop model by evaluating the platelet count and the level of the thrombin-antithrombin (TAT) complex, and investigating thrombus formation on the surface using scanning electron microscopy (SEM). We then assessed endothelial cell adhesion on the metal surfaces. In vitro blood tests revealed that, compared to a bare stent, the coating significantly inhibited platelet reduction and thrombus formation; more human serum albumin spontaneously adhered to the coated surface to block thrombogenic activation in the blood. Cell adhesion tests also indicated a significant increase in the number of cells adhering to the APTES-coated surfaces compared to the numbers adhering to either the bare stent or the stent coated with an anti-fouling phospholipid polymer. Finally, we performed an in vivo safety test by implanting coated stents into the internal thoracic arteries and ascending pharyngeal arteries of minipigs, and subsequently assessing the health status and vessel patency of the arteries by angiography over the course of 1 week. We found that there were no adverse effects on the pigs and the vascular lumens of their vessels were well maintained in the group with APTES-coated stents. Therefore, our new coating exhibited both high anti-thrombogenicity and cell-adhesion properties, which fulfill the requirements of an implantable stent.

Hydroxypropyl methylcellulose (HPMC) incorporated bio-composite films (unplasticized and plasticized) were prepared from pregelatinized maize starch/polyvinyl alcohol (PMS/PVA) blends by solution casting method. 10% boric acid (BA) was used as crosslinker. The physico-mechanical properties (tensile strength (TS), elongation at break (%EB), water solubility and moisture uptake) of the bio-composite films were studied. The thermo-chemical stability of the biofilms was studied by FT-IR, TGA and DSC analysis. TS, %EB, water solubility and moisture absorbency of 10% HPMC containing unplasticized films were found 38.1 MPa, 8.5%, 61% and 32.3%, respectively, however, the films were hard and brittle. On the contrary, TS, %EB, water solubility and moisture absorbency of 10% HPMC plasticized films were found 19.2 MPa, 28.5%, 62.2% and 57.3%. The biofilms exhibited relatively low water solubility and moisture uptake compared to higher HPMC containing composite. The thermo-chemical analysis revealed that the HPMC incorporated plasticized film was more thermally stable compared to pure PMS, PVA, HPMC and other bio composite films due to strong hydrogen bonding interaction with BA. The biodegradability of HPMC incorporated plasticized films was confirmed by soil burial test (anaerobic condition, RH 98%, 3 months). Therefore, the plasticized biofilm would be considered an alternative approach for biocompatible packaging material. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs), also known as nanoparticle-based fluorescent probes, are luminescent semiconductor particles with a size range of 2-20 nm. The unique optical and electronic capabilities of QDs have led to expanded applications in several fields such as optoelectronics, transistors, sensors, photodetection, catalysis, and medicine. The distinct quantum effects of nanocrystals can be controlled by changing their sizes and shapes using a variety of top-down and bottom-up tactics. QDs were traditionally fabricated using complex, expensive, toxic, and aggressive chemical techniques, which limited their application in a variety of disciplines. A unique approach for the biosynthesis of nanomaterials has been devised, which employs living organisms in the synthesis process and adheres to green chemistry principles. Biogenic QDs have favorable physicochemical features, biocompatibility, and fewer cytotoxic effects as a result of using natural biomolecules and enzymatic processes for mineralization, detoxification, and nucleation of metals and nonmetals to synthesize QDs. This is the first comprehensive review of its kind that highlights the synthesis of several doped and undoped QDs, including graphene QDs, carbon dots, silicon QDs, N/S-CDs, silver-CDs, cadmium-selenium QDs, and zinc oxide QDs, exclusively using photoautotrophic algae and plants. The different plausible mechanisms behind phyco- and phyto-fabrication of QDs are also discussed in detail along with their applications that include detection of organic and inorganic compounds, degradation of hazardous dyes, free radical scavenging, antimicrobial activity, cytotoxicity and bioimaging. Thus, this review aims to give valuable insights for the rational fabrication of photoluminescent nanomaterials with tunable structural and functional properties. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) provide promising power supply solutions by transforming mechanical energy into electrical energy. However, enhancing electrical performance of TENGs is essential for their widespread practical applications and commercialization. In this study, we fabricated TENGs in vertical contact‐separation mode using a tribopositive material—polyvinyl alcohol (PVA) slime—which is biocompatible, flexible, and wearable, decorated with graphene nanoplatelets (GnPs), and paired with tribonegative silicone. We analyzed the correlation between the electrical performance of the TENGs and the inherent triboelectric properties of the constituent material, including the evaluation of surface roughness, the measurement of the contact potential difference (CPD), and the material's dielectric constant. The incorporation of GnPs increased the dielectric constant of the composite material and its electron‐donating tendency, thus, increasing the contact potential difference. The GnPs concentration of 1 wt% was identified as the optimal value, resulting in a 42% increase in power density. The 1 wt% GnPs@PVA&Silicone TENG exhibited an open‐circuit voltage of 718 V and a peak power density of 15.3 W/m2. This study sheds light on enhancing the energy harvesting efficiency of TENGs through the utilization of biocompatible tribopositive and tribonegative materials. [ABSTRACT FROM AUTHOR]

Integrating superior mechanical performance, anisotropic conductivity, and biocompatibility into conductive hydrogels as all‐in‐one human‐machine interaction device remains challenging. Herein, by mimicking the anisotropic structures of human muscles, a robust anisotropic conductive hydrogel is developed by initially aligning polyvinyl alcohol with polypyrrole decorated cellulose nanofibrils to form an anisotropically oriented polymer networks, followed by post‐crosslinking with tannic acid (TA). Introducing TA into hydrogel network permanently secures its hierarchically anisotropic structure through multiple hydrogen bonds, thus endowing the hydrogel with exceptional mechanical properties (tensile strength of 11.41 MPa, toughness of 12.44 MJ m−3), anisotropic adhesive property, and direction‐dependent conductivity. With these attributes, a hydrogel strain sensor with excellent multidirectional sensitivity is developed, enabling stable monitoring of multi‐degrees of freedom joint movements in the human body and facilitating the control of a multiaxial virtual robot manipulator. Moreover, the in vitro/vivo tests demonstrate exceptional biocompatibility and anti‐biofouling properties of the as‐prepared hydrogel sensor, maintaining stable electronic response signals for over 14 days after successful implantation into the Achilles tendon of mice. Overall, this study presents a promising approach for designing conductive hydrogels with superior mechanical properties and anisotropic functionality for emerging applications in both in vitro and in vivo human‐machine interface materials. [ABSTRACT FROM AUTHOR]

Medically relevant biodegradable materials assist in the recovery of damaged tissue in the bones. Oral, cardiovascular, and orthopedic implants frequently use metallic implants. The incorporation of biodegradable metals (BMs) in medical applications is growing as a result of their suitability for use as temporary implants and their capacity to degrade once they accomplished their intended use. BMs have strong biocompatibility, which is the capacity of the substance to function with the proper host interaction in a specific situation. The implant will disintegrate during the healing process, preventing long‐term negative effects and the requirement for surgical removal. Because magnesium (Mg) is the body's fourth‐most plentiful element, its broken‐down by‐products can either be stored in new bone or calluses, or they can be released into circulation and eliminated through the urine. Mg is a biodegradable substance, although it has far lower corrosion resistance than other orthopedic implants. Mg‐based biomaterials are the most thoroughly researched and often used BMs due to their elastic modulus matching that of human bones, as well as their biosafety, biodegradability, and radiographic visibility. Thus, under this review, BM alloys, specifically Mg‐based metal alloys, and their properties, advantages, and challenges of Mg alloy were reviewed. [ABSTRACT FROM AUTHOR]

In this study, we have developed a Chitin(Ch)‐Poly(dioxanone)(PDO) gel system, which can be potentially used for tissue engineering. Hydrogel has been widely used in biomedical applications for its tuneable properties and biocompatibility. Chitin (Ch) is a natural biopolymer used for its ability to mimic the natural extracellular matrix due to its N‐acetyl glucosamine structural units. Poly (dioxanone) (PDO) is a FDA‐approved synthetic biopolymer known for its mechanical properties, good biocompatibility, and poor inflammatory response. Based on this, we have developed Ch‐PDO composite gel using simple regeneration chemistry and characterized it using FT‐IR and SEM. The developed composite gel showed improved gel strength, good swelling ability, and controlled degradation behaviour. It also showed good inject ability with shear thinning properties and hemocompatibility. Further, the biocompatibility and cell adhesion studies of the prepared gels were studied using dental follicle stem cells (DFSCs). The prepared Ch‐PDO gel was biocompatible and showed DFSCs cell attachment. Osteogenic mineralization, RUNX2 and OPN expression of the prepared Ch and Ch‐PDO gel was studied and Ch‐PDO gel showed an enhanced mineralization and RUNX2 and OPN expression showed enhanced osteogenic activity in Ch‐PDO. Therefore, the developed chitin‐PDO gel could be potentially used for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Long‐lasting vaginal dosage forms could improve the therapeutic efficacy of vaginal microbicides, but achieving long‐term delivery to the vaginal canal has been a significant challenge. To advance understanding of vaginal dosage retention and biodistribution, we describe a method of noninvasive imaging with 89Zr‐labeled bioadhesive nanoparticles (BNPs) in non‐human primates. We additionally examined the safety of repeated BNP application. BNPs administered vaginally to cynomolgus monkeys were still detected after 24 h (1.7% retention) and 120 h (0.1% retention). BNPs did not translocate to the uterus or into systemic circulation. Analysis of inflammatory biomarkers in the vaginal fluid and plasma suggest that BNPs are safe and biocompatible, even after multiple doses. BNPs are a promising delivery vehicle for vaginally administered therapeutics. Further studies using the non‐human primate imaging materials and methods developed here could help advance clinical translation of BNPs and other long‐lasting vaginal dosage forms. [ABSTRACT FROM AUTHOR]

Background/aim: The application of biocompatible heavy metal-free and cationic Ag2S NIR quantum dots (QDs), which have intense luminosity in the 700-900 nm medical range, as a nonviral gene delivery system paves the way to overcome autofluorescence and easily track the delivery of genes in real time. Materials and methods: The newly developed small and colloidally stable 2-mercaptopropionic acid (MPA)-capped Ag2S aqueous quantum dots electrostatically complexed with linear polyethyleneimine (Ag2S@2MPA/LPEI) were investigated for the first time both as a strong fluorescent probe and as a vector for nonviral gene delivery for the highest tracking of the system and delivery of genes into the nuclei of different cancer cells. The synthesized Ag2S@2MPA/LPEI quantum dots demonstrated strong optical imaging properties and were used to deliver a green fluorescent protein (GFP) plasmid as a standard gene. Results: For Ag2S@2MPA/LPEI-pDNA nanoparticles, an N/P ratio of 20 was the ideal transfection efficiency. Ag2S@2MPA/LPEI was substantially more compatible with HEK 293T cells than the free 25-kDa linear polyethylenimine (LPEI). Next, the transfection efficiency evaluation of pGFP genes with synthesized Ag2S@2MPA/LPEI and LPEI in different cancer cells demonstrated their high potential as a theranostic cancer gene delivery system. Conclusion: This is the first instance of gene transfection and optical imaging carried out in vitro using Ag2S@2MPA/LPEI QDs. Overall, the newly synthesized highly biocompatible and trackable Ag2S@2MPA/LPEI QDs can be an effective and biocompatible theranostic system for cancer gene therapy. [ABSTRACT FROM AUTHOR]

Cell-free wound dressings (WDs) with desirable effectiveness and safety have received much attention in the field of regenerative medicine. However, the weak linkages between bioactive polymers and the spatial structure of WDs frequently result in interventional treatment failure. Herein, we create a series of quaternized chitosan (QCS)-incorporated composite hydrogels (referred to as GHCH-n) by UV cross-linking and then convert them into microneedle patches (MNPs). QCS, which is positively charged and amphiphilic, is essential for broad-spectrum antibacterial and haemostatic activities. QCS is proven to be slightly toxic, so it is immobilized into the methacrylate gelatine (GelMA) molecular cage to minimize adverse effects. A polydimethylsiloxane micro-mould is used to shape the MNPs. MNPs can pierce tissue, seal off bleeding sites, and cling to wounds securely. Thus, MNPs can cooperate with GHCH-n hydrogels to halt bleeding and accelerate wound healing. This study recommends GHCH-10 MNPs as an advanced biomaterial. Several preclinical research models have thoroughly validated the application effect of GHCH-10 MNPs. This research also proposes a novel strategy for integrating the nature of bioactive polymers and the structure of composite biomaterials. This strategy is not only applicable to the fabrication of next-generation WDs but also shows great potential in expanding interdisciplinary domains. [ABSTRACT FROM AUTHOR]

Tunable hydrogels have gained significant attention in the bioengineering field due to their designer preparation approach. Towards this end, gelatine stands out as a promising candidate owing to its desirable attributes, such as biocompatibility, ability to support cell adhesion and proliferation, biodegradability, and cost-effectiveness. This study presents the preparation of a robust gelatine hydrogel employing sacran aldehyde (SDA) as a natural cross-linker. The resulting SDA-cross-linked gelatine hydrogels (GSDA) display an optimal compressive stress of 0.15 MPa at 50% strain, five times higher than pure gelatine hydrogel. As SDA cross-linking concentration is increased, the swelling capacity of GSDA declines. This decline in swelling capacity, from 80% to 40%, is a result of strong crosslinking of gelatin with SDA. Probing further with FT-IR spectroscopy and SEM at the micron scale unveiled a dual-cross-linking mechanism within the hydrogels. This mechanism encompasses both short- and long-range covalent cross-linking, along with thermo-induced physical cross-linking, resulting in a significant enhancement of the load-bearing capacity of the fabricated hydrogels. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) are receiving increasing interest in biomedical applications. However, due to their large surface area, in physiological environments, they tend to interact with plasma proteins, inducing their agglomeration and ultimately resulting in a substantial efficiency decrease in diagnostic and therapeutic applications. To overcome such problems, NPs are typically coated with a layer of hydrophilic and biocompatible polymers, such as PEG chains. However, few examples exist in which this property could be systematically fine-tuned and combined with added properties, such as emission. Herein, we report a novel mussel-inspired catechol-based strategy to obtain biocompatible and multifunctional coatings, using a previously developed polymerization methodology based on the formation of disulfide bridges under mild oxidative conditions. Two families of NPs were selected as the proof of concept: mesoporous silica NPs (MSNPs), due to their stability and known applications, and magnetite NPs (Fe3O4 NPs), due to their small size (<10 nm) and magnetic properties. The PEG coating confers biocompatibility on the NPs and can be further functionalized with bioactive molecules, such as glucose units, through the end carboxylic acid moieties. Once we demonstrated the feasibility of our approach to obtaining PEG-based coatings on different families of NPs, we also obtained multifunctional coatings by incorporating fluorescein functionalities. The resulting coatings not only confer biocompatibility and excellent cell internalization, but also allow for the imaging and tracking of NPs within cells. [ABSTRACT FROM AUTHOR]

A cleanroom free optimized fabrication of a low-cost facile tungsten diselenide (WSe2) combined with chitosan-based hydrogel device is reported for multifunctional applications including tactile sensing, pulse rate monitoring, respiratory rate monitoring, human body movements detection, and human electrophysiological signal detection. Chitosan being a natural biodegradable, non-toxic compound serves as a substrate to the semiconducting WSe2 electrode which is synthesized using a single step hydrothermal technique. Elaborate characterization studies are performed to confirm the morphological, structural, and electrical properties of the fabricated chitosan/WSe2 device. Chitosan/WSe2 sensor with copper contacts on each side is put directly on skin to capture human body motions. The resistivity of the sample was calculated as 26 kΩ m−1. The device behaves as an ultrasensitive pressure sensor for tactile and arterial pulse sensing with response time of 0.9 s and sensitivity of around 0.02 kPa−1. It is also capable for strain sensing with a gauge factor of 54 which is significantly higher than similar other reported electrodes. The human body movements sensing can be attributed to the piezoresistive character of WSe2 that originates from its non-centrosymmetric structure. Further, the sensor is employed for monitoring respiratory rate which measures to 13 counts/min for healthy individual and electrophysiological signals like ECG and EOG which can be used later for detecting numerous pathological conditions in humans. Electrophysiological signal sensing is carried out using a bio-signal amplifier (Bio-Amp EXG Pill) connected to Arduino. The skin-friendly, low toxic WSe2/chitosan dry electrodes pave the way for replacing wet electrodes and find numerous applications in personalized healthcare. [ABSTRACT FROM AUTHOR]

Chronic wounds often result in multiple infections with various kinds of bacteria and uncontrolled wound exudate, resulting in several healthcare issues. Advanced medicated nanofibres prepared by electrospinning have gained much attention for their topical application on infected chronic wounds. The objective of this work is to enhance the critical variables of ciprofloxacin-loaded polycaprolactone-silk sericin (PCL/SS-PVA-CIP) nanofibre production via the process of electrospinning. To examine the antibacterial effectiveness of PCL/SS-PVA-CIP nanocomposites, the material was tested against P. aeruginosa and S. aureus. The combination of PCL/SS-PVA-CIP exhibited potent inhibitory properties, with the most effective concentrations of ciprofloxacin (CIP) being 3 μg/g and 7.0 μg/g for each bacterium, respectively. The biocompatibility was evaluated by conducting cell reduction and proliferation studies using the human epidermal keratinocyte (HaCaT) cells and human gingival fibroblasts (HGFs) in vitro cell lines. The PCL/SS-PVA-CIP showed good cell compatibility with HaCaT and HGF cells, with effective proliferation even at antibiotic doses of up to 7.0 μg/g. The drug release effectiveness of the nanocomposites was assessed at various concentrations of CIP, resulting in a maximum cumulative release of 76.5% and 74.4% after 72 h for CIP concentrations of 3 μg/g and 7 μg/g, respectively. In summary, our study emphasizes the possibility of combining silk sericin (SS) and polycaprolactone (PCL) loading with CIP nanocomposite for wound management. [ABSTRACT FROM AUTHOR]

[Display omitted] The triboelectric nanogenerator (TENG) of natural biomaterials is a new type of energy harvesting device and can be used as a self-powered sensor, which has received extensive research and attention. In this paper, based on the biocompatibility of chitosan and chondroitin sulfate, ZnO-modified chitosan/chondroitin sulfate/ZnO TENG was prepared for research on wearable devices and sustainable power supply devices. This study employs molecular dynamics to compute the interaction energy between chitosan and ZnO molecules. Theoretical calculations have unequivocally substantiated the occurrence of a binding interaction between these two molecular entities. The effect of ZnO on chitosan/chondroitin sulfate morphology was investigated by atomic force microscopy. The chitosan/chondroitin sulfate/ZnO TENG has high flexibility and electrical output performance. It can reach 105 V and 3.3 µA of open-circuit voltage and short-circuit current. Chitosan/chondroitin Sulfate/ZnO TENG successfully converts the mechanical energy of human motion into electrical energy. Strong electrical signals are exhibited when making fists and waving fingers and wrists. The TENG is a self-powered source and lights up 70 blue light-emitting diodes (LEDs). The chitosan/chondroitin sulfate/ZnO TENG has demonstrated its capabilities in energy harvesting and wearable self-powered sensors. [ABSTRACT FROM AUTHOR]

Natural hydrogels are widely employed in tissue engineering and have excellent biodegradability and biocompatibility. Unfortunately, the utilization of such hydrogels in the field of three‐dimensional (3D) printing nasal cartilage is constrained by their subpar mechanical characteristics. In this study, we provide a multicrosslinked network hybrid ink made of photocurable gelatin, hyaluronic acid, and acrylamide (AM). The ink may be processed into intricate 3D hydrogel structures with good biocompatibility and high stiffness properties using 3D printing technology based on digital light processing (DLP), including intricate shapes resembling noses. By varying the AM content, the mechanical behavior and biocompatibility of the hydrogels can be adjusted. In comparison to the gelatin methacryloyl (GelMA)/hyaluronic acid methacryloyl (HAMA) hydrogel, adding AM considerably enhances the hydrogel's mechanical properties while also enhancing printing quality. Meanwhile, the biocompatibility of the multicrosslinked network hydrogels and the development of cartilage were assessed using neonatal Sprague–Dawley (SD) rat chondrocytes (CChons). Cells sown on the hydrogels considerably multiplied after 7 days of culture and kept up the expression of particular proteins. Together, our findings point to GelMA/HAMA/polyacrylamide (PAM) hydrogel as a potential material for nasal cartilage restoration. The photocuring multicrosslinked network ink composed of appropriate proportions of GelMA/HAMA/PAM is very suitable for DLP 3D printing and will play an important role in the construction of nasal cartilage, ear cartilage, articular cartilage, and other tissues and organs in the future. Notably, previous studies have not explored the application of 3D‐printed GelMA/HAMA/PAM hydrogels for nasal cartilage regeneration. [ABSTRACT FROM AUTHOR]

The developments of nano-roughness surface textures are important to implement enhanced osseointegration, cell adhesion, and proliferation in polymers for biomedical applications such as tissue engineering scaffolds and orthopaedic implants. The hydrophilicity of the polymeric implants is a crucial factor for cell adhesion, which can be improved via adapting the roughness of the surface. This study explores the surface modification of poly (lactic acid) (PLA) polymer through an alkaline wet etching process, varying alkaline concentration and etching time under both room temperature and elevated conditions. The main objective is to refine the PLA surface through wet etching, altering its properties for potential use in biomedical contexts. The assessment of surface roughness is conducted through scanning electron microscopy (SEM), atomic force microscopy (AFM), and fourier-transform infrared spectroscopy (FTIR). These techniques offer a comprehensive analysis of surface topography, nanoscale roughness, and potential chemical changes resulting from the wet etching process. The nano-roughness of treated 3D printed PLA was increased by 1.4 times compared to the control 3D printed PLA. The research contributes to the broader field of biomaterial engineering, laying the groundwork for subsequent investigations that will focus on applying the derived conclusions to enhance PLA’s biocompatibility and functionality in tissue engineering and orthopaedic applications.

AbstractFabrication of haemostatic materials with excellent antimicrobial, biocompatible and biodegradable properties remains as a major challenge in the field of medicine. Haemostatic agents play vital role in protecting patients and military individuals during emergency situations. Natural polymers serve as promising materials for fabricating haemostatic compounds due to their efficacy in promoting hemostasis and wound healing. In the present work, sodium alginate/aloe vera/sericin (SA/AV/S) scaffold has been fabricated using a simple cost-effective casting method. The prepared SA/AV/S scaffolds were characterised for their physicochemical properties such as scanning electron microscope, UV–visible spectroscopy and Fourier transform infra-red spectroscopy. SA/AV/S scaffold showed good mechanical strength, swelling behaviour and antibacterial activity. In vitro experiments using erythrocytes proved the hemocompatible and biocompatible features of SA/AV/S scaffold. In vitro blood clotting assay performed using human blood demonstrated the haemostatic and blood absorption properties of SA/AV/S scaffold. Scratch wound assay was performed to study the wound healing efficacy of prepared scaffolds. Chick embryo chorioallantoic membrane assay carried out using fertilised embryos proved the angiogenic property of SA/AV/S scaffold. Thus, SA/AV/S scaffold could serve as a potential haemostatic healthcare product due to its outstanding haemostatic, antimicrobial, hemocompatible, biocompatible and angiogenic properties.

Tunable hydrogels have gained significant attention in the bioengineering field due to their designer preparation approach. Towards this end, gelatine stands out as a promising candidate owing to its desirable attributes, such as biocompatibility, ability to support cell adhesion and proliferation, biodegradability, and cost-effectiveness. This study presents the preparation of a robust gelatine hydrogel employing sacran aldehyde (SDA) as a natural cross-linker. The resulting SDA-cross-linked gelatine hydrogels (GSDA) display an optimal compressive stress of 0.15 MPa at 50% strain, five times higher than pure gelatine hydrogel. As SDA cross-linking concentration is increased, the swelling capacity of GSDA declines. This decline in swelling capacity, from 80% to 40%, is a result of strong crosslinking of gelatin with SDA. Probing further with FT-IR spectroscopy and SEM at the micron scale unveiled a dual-cross-linking mechanism within the hydrogels. This mechanism encompasses both short- and long-range covalent cross-linking, along with thermo-induced physical cross-linking, resulting in a significant enhancement of the load-bearing capacity of the fabricated hydrogels.

Abstract The limitations associated with conventional cancer treatment modalities, particularly for breast cancer, underscore the imperative for developing safer and more productive drug delivery systems. A promising strategy that has emerged is the combination of chemotherapy with gas therapy. We synthesized curcumin-loaded amorphous calcium carbonate nanoparticles (Cur-CaCO3) via a gas diffusion reaction in the present study. Subsequently, a "one-step" ethanol injection method was employed to fabricate lipid-coated calcium carbonate nanoparticles (Cur-CaCO3@LA-Lip) loaded with L-arginine, aimed at harnessing the synergistic effects of chemotherapy and nitric oxide to enhance antitumor efficacy. Transmission electron microscopy analysis revealed that Cur-CaCO3@LA-Lip nanoparticles were subspherical with a distinct lipid layer encapsulating the periphery. Fourier transform infrared spectroscopy, X-ray powder diffraction, and differential scanning calorimetry results confirmed the successful synthesis of Cur-CaCO3@LA-Lip. The nanoparticles exhibited significant drug loading capacities of 8.89% for curcumin and 3.1% for L-arginine. In vitro and in vivo assessments demonstrated that Cur-CaCO3@LA-Lip nanoparticles facilitated sustained release of curcumin and exhibited high cellular uptake, substantial tumor accumulation, and excellent biocompatibility. Additionally, the nanoparticles showed robust cytotoxicity and potent antitumor efficacy, suggesting their potential as a formidable candidate for breast cancer therapy.

Objective To investigate the physicochemical and biological properties of a new calcium sulfate-based root canal sealer for deciduous teeth containing calcium sulfate hemihydrate, barium sulfate, chlorhexidine acetate, and polyethylene glycol 400 (PEG 400). Methods This study was reviewed and approved by the Ethics Committee. The calcium sulfate hemihydrate and barium sulfate powders with different mass percentages were mixed with liquid PEG 400 at a powder-to-liquid ratio of 3∶1, and chlorhexidine acetate was added to a concentration of 0.2 mg/mL according to the volume of PEG 400. The above materials were mechanically ground at 250 r/min for 24 h to obtain a calcium sulfate-based root canal sealer for deciduous teeth. The sealer was classified into different groups according to mass percentages of components. The mass percentages of components were optimized by performing time, fluidity, and radiopacity experiments, and then the pH, mass loss in vitro, and microscopic morphology of the optimal sealer were evaluated. The antimicrobial properties of the sealer were evaluated by a bacterial-material cocultivation method. The cytocompatibility of the sealer was evaluated by a CCK-8 assay and cytomorphological staining, and its biocompatibility was evaluated by a subcutaneous tissue embedding assay. Results After optimization, mass percentage of calcium sulfate hemihydrate was 80 wt%, and the mass percentage of barium sulfate was 20 wt%. The flowability and radiopacity of the sealer were in accordance with international standards. The pH stabilized between 6-7. On the 7th and 14th days, the pH in the water group was significantly greater than that in the PBS group (PP>0.05). In vitro degradation experiments, the mass loss of the sealer was approximately 15.17% during the preimmersion period, and rate of mass loss decreased after 3 weeks, reaching only approximately 8.33%. X-ray diffraction (XRD) and scanning electron microscopy (SEM) revealed that the main component of the sealer after hydration was calcium sulfate dehydrate. In bacterial growth assays and cytological tests, the sealer showed significant inhibition of the growth of E. faecalis (PPP>0.05). Both the sealer group and the control group (Vitapex and zinc oxide eugenol) caused mild inflammatory reactions in tissue sections. Conclusion In this study, a new type of root canal sealer for deciduous teeth was designed based on calcium sulfate, which has good physicochemical properties and strong antibacterial properties and meets biocompatibility requirements. This study provides an idea for the development of a new type of root canal sealer for deciduous teeth.

Abstract The exploration of newer antibacterial strategies is driven by antibiotic‐resistant microbes that cause serious public health issues. In recent years, nanoscale materials have developed as an alternative method to fight infections. Despite the fact that many nanomaterials have been discovered to be harmful, numerous researchers have shown a keen interest in nanoparticles (NPs) made of noble metals like silver, gold and platinum. To make environmentally safe NPs from plants, green chemistry and nanotechnology have been combined to address the issue of toxicity. The study of bimetallic nanoparticles (BNPs) has increased tremendously in the past 10 years. The production of BNPs mediated by natural extracts is straightforward, low cost and environmentally friendly. Due to their low toxicity, safety and biological stability, noble BNPs with silver, gold, platinum and palladium have the potential to be used in biomedical applications. They have a significant impact on human health and are used in medicine and pharmacy due to their biological characteristics, which include catalytic, antioxidant, antibacterial, antidiabetic, anticancer, hepatoprotective and regenerative activity.

Objectives The micro‐nano structure of 3D‐printed porous titanium (Ti) alloy with excellent performance in avoiding stress shielding and promoting bone tissue differentiation provides a new opportunity for the development of bone implants, but it necessitates higher requirements for bone tissue differentiation and the antibacterial properties of bone implants in clinical practice. Methods This study investigated the preparation, antimicrobial properties, and osteogenesis‐promoting ability of the 3D printed porous Ti alloy anodic oxidized Ag‐carrying (Ag@3D‐TiO2) scaffolds. The 3D printed porous Ti alloy (3D‐Ti), anodized 3D printed porous Ti alloy (3D‐TiO2), and Ag@3D‐TiO2 scaffolds were synthesized using electron beam melting. The antimicrobial properties of the scaffolds were examined using antibacterial tests and their cytocompatibility was assessed using a cell proliferation assay and acridine orange/ethidium bromide (AO/EB) staining. In vitro cellular assays were used to investigate the effects of the scaffold microstructural features on cell activity, proliferation, and osteogenesis‐related genes and proteins. In vivo animal experiments were used to evaluate the anti‐inflammatory and osteogenesis‐promoting abilities of the scaffolds. Results The Ag@3D‐TiO2 scaffolds exhibited sustained anti‐microbial activity over time, enhanced cell proliferation, facilitated osteogenic differentiation, and increased extracellular matrix mineralization. In addition, alkaline phosphatase (ALP), collagen type I (COL‐I), and osteocalcin (OCN)‐related genes and proteins were upregulated. In vivo animal implantation experiments, the anti‐inflammatory effect of the Ag@3D‐TiO2 scaffolds were observed using histology, and a large amount of fibrous connective tissue was present around it; the Ag@3D‐TiO2 scaffolds were more bio‐compatible with the surrounding tissues compared with 3D‐Ti and 3D‐TiO2; a large amount of uniformly distributed neoplastic bone tissue existed in their pores, and the chronic systemic toxicity test showed that the 3D‐Ti, 3D‐TiO2, and Ag@3D‐TiO2 scaffolds are biologically safe. Conclusion The goal of this study was to create a scaffold that exhibits antimicrobial properties and can aid bone growth, making it highly suitable for use in bone tissue engineering.

Due to their great physical and mechanical behaviors, polymers have become essential in various industries. Polymers have been produced using chemical monomer synthesis, potentially dangerous non-biodegradable waste in the environment. Therefore, biopolymers are introduced, and organic compounds are found in natural sources as monomeric units. Also, biopolymers were discovered to be biodegradable and biocompatible, and these biopolymers are beneficial in numerous applications. Natural plant fibers have drawn more attention recently as potential reinforcing materials. The composites made with natural fibers have excellent mechanical and thermal characteristics. Materials made of natural fibers are inexpensive, recyclable, and environmentally beneficial. These natural fibers are excellent candidates to replace conventional fibers due to their biodegradability and eco-friendliness. The adhesion between the fibers and matrix has the most impact on the mechanical characteristics of composites. The mechanical characteristics of the composites were improved by combining chemical and physical modification techniques to increase fiber–matrix adhesion. The main objective of this study is to provide a thorough understanding of common types of biopolymers, various natural fibers, fillers, chemical treatments, and the performance of biopolymers and their composites-reinforced natural fibers. Moreover, the characterization and application of various biopolymers and composites were reviewed. [ABSTRACT FROM AUTHOR]

Zinc chalcogenide nanostructures are an important class of non-toxic nanomaterials due to their biocompatible nature, surface flexibility, high degree of crystallinity, and high photoluminescence efficiency that makes them applicable in solar cells biosensors, photocatalysts, LEDs, and electroluminescence materials. There are various methods for synthesizing zinc chalcogenides, including ZnS, ZnSe, and ZnTe, through colloidal, hydrothermal, solvothermal, microwave, and core shell synthesis to prepare highly luminescent material for drug delivery and biomedical applications. The main focus of this review is to explore various synthetic approaches to tune the morphology, size, and surface properties of zinc-based chalcogenide nanostructures, revealing their potential as biocompatible quantum dots. Despite their advantages, zinc chalcogenides also have certain drawbacks, such as low mechanical strength, limited bandgap tunability, and less thermal stability, that can point the way for future research. Thus, this review may prove beneficial for developing and designing more advanced nanomaterials based on existing knowledge, protocols, and strategies. [ABSTRACT FROM AUTHOR]

Generally, an esterase lipase enzyme can hydrolyze specific substrates called esters in an aqueous solution. Herein, we investigate how a G‐quadruplex self‐assembly affects the hydrolysis equilibrium in reverse. The biocatalyst, lipase, activates the individual building‐blocks through fuel consumption, causing them to undergo a higher degree of self‐organization into nanofibers within spheres. We have synthesized five peptide‐lipid‐conjugated guanine base functionalized molecules to explore how the equilibrium can be shifted through reverse hydrolysis. Among these, NAC5 self‐assembled into a G‐quadruplex structure which has been confirmed by various spectroscopic techniques. The wide‐angle powder XRD, ThT dye binding assay and circular dichroism study is carried out to support the presence of the G‐quadruplex structure. The biocatalytic formation of nanofibers enclosed spheres is analyzed using CLSM, FE‐SEM and HR‐TEM experiments. Additionally, we assess the biocompatibility of the enzyme fueled dissipative self‐assembled fibers enclosed spheres, as they have potential applications as a biomaterial in protocells. MTT assay is performed to check the cytotoxicity of G‐quadruplex hydrogel, using HEK 293 and McCoy cell lines for viability assessment. Finally, the utility of the novel NAC5 hydrogel as a wound repairing biomaterial is demonstrated by cell migration experiment in a scratch assay. [ABSTRACT FROM AUTHOR]

The limitations associated with conventional cancer treatment modalities, particularly for breast cancer, underscore the imperative for developing safer and more productive drug delivery systems. A promising strategy that has emerged is the combination of chemotherapy with gas therapy. We synthesized curcumin-loaded amorphous calcium carbonate nanoparticles (Cur-CaCO3) via a gas diffusion reaction in the present study. Subsequently, a "one-step" ethanol injection method was employed to fabricate lipid-coated calcium carbonate nanoparticles (Cur-CaCO3@LA-Lip) loaded with L-arginine, aimed at harnessing the synergistic effects of chemotherapy and nitric oxide to enhance antitumor efficacy. Transmission electron microscopy analysis revealed that Cur-CaCO3@LA-Lip nanoparticles were subspherical with a distinct lipid layer encapsulating the periphery. Fourier transform infrared spectroscopy, X-ray powder diffraction, and differential scanning calorimetry results confirmed the successful synthesis of Cur-CaCO3@LA-Lip. The nanoparticles exhibited significant drug loading capacities of 8.89% for curcumin and 3.1% for L-arginine. In vitro and in vivo assessments demonstrated that Cur-CaCO3@LA-Lip nanoparticles facilitated sustained release of curcumin and exhibited high cellular uptake, substantial tumor accumulation, and excellent biocompatibility. Additionally, the nanoparticles showed robust cytotoxicity and potent antitumor efficacy, suggesting their potential as a formidable candidate for breast cancer therapy. [ABSTRACT FROM AUTHOR]

Bone tissue engineering (BTE) is an important field of research, essential in order to heal bone defects or replace impaired tissues and organs. As one of the most used additive manufacturing processes, 3D printing can produce biostructures in the field of tissue engineering for bones, orthopaedic tissues, and organs. Scaffold manufacturing techniques and suitable materials with final structural, mechanical properties, and the biological response of the implanted biomaterials are an essential part of BTE. In fact, the scaffold is an essential component for tissue engineering where cells can attach, proliferate, and differentiate to develop functional tissue. Fused deposition modelling (FDM) is commonly employed in the 3D printing of tissue-engineering scaffolds. Scaffolds must have a good architecture, considering the porosity, permeability, degradation, and healing capabilities. In fact, the architecture of a scaffold is crucial, influencing not only the physical and mechanical properties but also the cellular behaviours of mesenchymal stem cells. Cells placed on/or within the scaffolds is a standard approach in tissue engineering. For bio-scaffolds, materials that are biocompatible and biodegradable, and can support cell growth are the ones chosen. These include polymers like polylactic acid (PLA), polycaprolactone (PCL), and certain bioglass or composite materials. This work comprehensively integrates aspects related to the optimisation of biocompatible and biodegradable composites with the low cost, simple, and stable FDM technology to successfully prepare the best designed composite porous bone-healing scaffolds. FDM can be used to produce low-cost bone scaffolds, with a suitable porosity and permeability. [ABSTRACT FROM AUTHOR]

Today, the transformation of polymers into useful structures for the human body in medical field has been an interesting subject that affected everyone. Synthetic polymers have a wide range of uses in the health sector such as coating, cardiovascular, orthodontic surgery, tissue engineering, implant, and drug carrier with the development of technology. These polymers are known as polymers with various characteristics and applications artificially synthesized in accordance with chemical and thermodynamic laws. The polymers in health sector have a share of 41% in drug and release studies, 18% in treatment with therapy applications, 10% in vaccine production, 31% in studies on new approaches in this field. Synthetic polymers have ability to be produced cheaply and easily in large quantities. In this study, synthetic polymers such as polyethylene glycol, polyvinyl alcohol, polyurethane, polyolefin, polytetrafluoroethylene, silicone, polyvinyl chloride, poly-methyl methacrylate, polyester, polyamide and poly-lactic acid were investigated and details regarding the applications with explications of polymers were provided. It was seen that synthetic polymers could be evaluated in treatment of cancer and chronic diseases by determining the most appropriate methods and techniques with biocompatible, biodegradable, non-toxic materials. [ABSTRACT FROM AUTHOR]

This study aims to establish and optimize a process for the fabrication of 3D microstructures of the biocompatible polymer Parylene C using hot embossing techniques. The different process parameters such as embossing temperature, embossing force, demolding temperature and speed, and the usage of a release agent were optimized, utilizing adhesive micropillars as a use case. To enhance compatibility with conventional semiconductor fabrication techniques, hot embossing of Parylene C was adapted from conventional stainless steel substrates to silicon chip platforms. Furthermore, this adaptation included an investigation of the effects of the hot embossing process on metal layers embedded in the Parylene C, ensuring compatibility with the ultra-thin Parylene printed circuit board (PCB) demonstrated previously. To evaluate the produced microstructures, a combination of characterization methods was employed, including light microscopy (LM) and scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy (FTIR). These methods provided comprehensive insights into the morphological, chemical, and structural properties of the embossed Parylene C. Considering the improved results compared to existing patterning techniques for Parylene C like plasma etching or laser ablation, the developed hot embossing approach yields a superior structural integrity, characterized by increased feature resolution and enhanced sidewall smoothness. These advancements render the method particularly suitable for diverse applications, including but not limited to, sensor optical components, adhesive interfaces for medical wearables, and microfluidic systems. [ABSTRACT FROM AUTHOR]

Polyvinyl Alcohol (PVA) has been used in various applications, including the medical health industry and electronics. It is a synthetic polymer with advantages such as being transparent, flexible, biocompatible, biodegradable, and a simpler synthesis process. These advantages make PVA a very promising material for human wearable antennae. In this research, the bending effect of an antenna using a PVA substrate is studied to analyze its durability in the wearable application. Firstly, the thin film substrate synthesis is performed using PVA 2488 with the measured average dielectric constant and tangent loss of 1.24 and 0.066, respectively, across S-Band frequency. Later, a 5G antenna is designed and fabricated using the PVA substrate. Finally, the bending effects of the fabricated antenna are measured at different bending radii. Four different antenna-bending radii are selected to represent different curvatures of human body parts. Results show that bending does not have a significant effect on the reflection coefficient of the antenna, where the frequency shifts from 2.2% up to 7.4% only for all bending conditions. Hence, in that aspect of finding, the PVA thin film is a potential candidate for flexible and wearable antenna material in various human body parts in biomedical applications. [ABSTRACT FROM AUTHOR]

The increasing incidence of breast cancer and bacterial biofilm in medical devices significantly heightens global mortality and morbidity, challenging synthetic drugs. Consequently, greener-synthesized nanomaterials have emerged as a versatile alternative for various biomedical applications, offering new therapeutic avenues. This study explores the synthesis of biocompatible zinc oxide (ZnONPs) nanoparticles using Gymnema sylvestre and its antibacterial, antibiofilm, and cytotoxic properties. Characterization of ZnONPs inferred that UV–Vis spectra exhibited a sharp peak at 370 nm. Fourier transform infrared spectroscopical analysis revealed the presence of active functional groups such as aldehyde, alkyne, cyclic alkene, sulfate, alkyl aryl ether, and Zn–O bonds. X-ray diffraction analysis results confirmed the crystalline nature of the nanoparticle. Scanning electron microscope analysis evidenced hexagonal morphology, and energy-dispersive X-ray analysis confirmed zinc content. High-resolution transmission electron microscope analysis showed hexagonal and rod-shaped ZnONPs with a size of 5 nm. Zeta potential results affirmed the stability of nanoparticles. The ZnONPs effectively inhibited gram-positive (18–20 mm) than gram-negative (12–18 mm) bacterial pathogens with lower bacteriostatic and higher bactericidal values. Biofilm inhibitory property inferred ZnONPs were more effective against gram-positive (38–94%) than gram-negative bacteria (27–86%). The concentration of ZnONPs to exert 50% biofilm-inhibitory is lower against gram-positive bacteria (179.26–203.95 μg/mL) than gram-negative bacteria (201.46–236.19 μg/mL). Microscopic visualization inferred that at 250 μg/mL, ZnONPs strongly disrupted biofilm formation, as evidenced by decreased biofilm density and altered architecture. The cytotoxicity of ZnONPs against breast cancer cells showed a dose-dependent reduction in cell viability with an IC50 value of 19.4 µg/mL. AO/EB staining indicated early and late apoptotic cell death of breast cancer cells under fluorescence microscopy. The results of hemolytic activity validated the biocompatibility of the ZnONPs. Thus, the unique properties of the green-synthesized ZnONPs suggest their potential as effective drug carriers for targeted delivery in cancer therapy and the treatment of biofilm-related infections. [ABSTRACT FROM AUTHOR]

As micron-sized objects, mobile microrobots have shown significant potential for future biomedical applications, such as targeted drug delivery and minimally invasive surgery. However, to make these microrobots viable for clinical applications, several crucial aspects should be implemented, including customizability, motion-controllability, imageability, biodegradability, and biocompatibility. Developing materials to meet these requirements is of utmost importance. Here, a gelatin methacryloyl (GelMA) and (2-(4-vinylphenyl)ethene-1,1,2-triyl)tribenzene (TPEMA)-based multifunctional hydrogel with 3D printability, fluorescence imageability, biodegradability, and biocompatibility is demonstrated. By using 3D direct laser writing method, the hydrogel exhibits its versatility in the customization and fabrication of 3D microstructures. Spherical hydrogel microrobots were fabricated and decorated with magnetic nanoparticles on their surface to render them magnetically responsive, and have demonstrated excellent movement performance and motion controllability. The hydrogel microstructures also represented excellent drug loading/release capacity and degradability by using collagenase, along with stable fluorescence properties. Moreover, cytotoxicity assays showed that the hydrogel was non-toxic, as well as able to support cell attachment and growth, indicating excellent biocompatibility of the hydrogel. The developed multifunctional hydrogel exhibits great potential for biomedical microrobots that are integrated with customizability, 3D printability, motion controllability, drug delivery capacity, fluorescence imageability, degradability, and biocompatibility, thus being able to realize the real in vivo biomedical applications of microrobots. [ABSTRACT FROM AUTHOR]

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A wound dressing is important to ensure an efficient healing process while protecting the wound area. This research study combined 2-hydroxyethyl cellulose (2HEC)—an etherified cellulose derivative with salicylic acid (SA) to develop a single layer and investigate the 2HEC viability as wound dressing material. Nine different samples with different compositions of SA, from 5 wt.% to 40 wt.% (with an interval of 5 wt.%) and one control sample without adding SA were prepared via the solution casting method. The 2HEC-SA films were studied regarding the effects of SA composition on antimicrobial properties (Staphylococcus aureus) via the well-diffusion method. Additionally, degradability, mechanical properties, X-ray diffraction (XRD), and Fourier transform infrared (FTIR) of 2HEC-SA films have also been tested. The strongest antimicrobial effect of 2HEC-SA film was obtained at 40 wt.% with a 16 mm inhibition zone diameter. There was a noticeable decreasing weight loss pattern in the degradation test and the tensile strength of 2HEC-SA film when the composition of salicylic acid is increased. 2HEC-SA film changes phases from amorphous to crystalline starting at 25 wt.% of salicylic acid as seen through XRD, while FTIR shows that complexation of 2HEC and salicylic acid occurred at 1050 cm−1. [ABSTRACT FROM AUTHOR]

The need to create safe materials for biomedical and pharmaceutical applications has become a significant driving force for the development of new systems. Therefore, a chitosan-coated copolymer of itaconic acid, acrylic acid, and N-vinyl caprolactam (IT-AA-NVC) was prepared by radical polymerization and subsequent coating via nanoprecipitation to give a system capable of sustained delivery of melatonin. Although melatonin brings undoubted benefits to the human body, aspects of the optimal dose, route, and time of administration for the obtaining of suitable treatment outcomes remain under discussion. The entrapment of melatonin in biocompatible polymeric systems can prevent its oxidation, decrease its toxicity, and provide an increased half-life, resulting in an enhanced pharmacokinetic profile with improved patient compliance. The structures of the biopolymer and conjugate were proven by FTIR, thermal properties were tested by DSC, and the morphologies were followed by SEM. The loading efficiency and in vitro release profile were studied by means of HPLC, and a delayed release profile with an initial burst was obtained. The potential systemic toxicity of the formulation was studied in vivo; a mild hepatotoxicity was observed following administration of the melatonin-loaded formulation to mice, both by histopathology and blood clinical biochemistry. Histopathology showed a mild nephrotoxicity as well; however, kidney clinical biochemistry did not support this. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) represent a promising avenue for sustainable energy production by harnessing the metabolic activity of microorganisms. In this study, a novel design of MFC—a Microfluidic Benthic Microbial Fuel Cell (MBMFC)—was developed, fabricated, and tested to evaluate its electrical energy generation. The design focused on balancing microfluidic architecture and wiring procedures with microbial community dynamics to maximize power output and allow for upscaling and thus practical implementation. The testing phase involved experimentation to evaluate the performance of the MBMFC. Microbial feedstock was varied to assess its impact on power generation. The designed MBMFC represents a promising advancement in the field of bioenergy generation. By integrating innovative design principles with advanced fabrication techniques, this study demonstrates a systematic approach to optimizing MFC performance for sustainable and clean energy production. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA) is a highly biocompatible material that has similar properties to human bone. Researchers have adopted different methods for the synthesis of HA from different natural sources. This paper addresses the synthesis method of nano-hydroxyapatite (n-HA) from Hilsha Fishbone. The synthesized n-HA has been characterized by UV, FTIR, TEM, XRD and cytotoxicity analysis. The successful synthesis of n-HA has been confirmed by the peak formation in the UV analysis. The presence of functional groups has been identified by the FTIR analysis. According to the TEM images, the synthesized n-HA is irregular in size and shape. Based on the XRD analysis, the formation of crystals by the n-HA has been assured. The in-vitro cytotoxicity analysis confirmed the bio-safety of the synthesized n-HA. Based on the findings, the synthesized n-HA can be applied in different biomedical applications. [ABSTRACT FROM AUTHOR]

Objectives: The micro‐nano structure of 3D‐printed porous titanium (Ti) alloy with excellent performance in avoiding stress shielding and promoting bone tissue differentiation provides a new opportunity for the development of bone implants, but it necessitates higher requirements for bone tissue differentiation and the antibacterial properties of bone implants in clinical practice. Methods: This study investigated the preparation, antimicrobial properties, and osteogenesis‐promoting ability of the 3D printed porous Ti alloy anodic oxidized Ag‐carrying (Ag@3D‐TiO2) scaffolds. The 3D printed porous Ti alloy (3D‐Ti), anodized 3D printed porous Ti alloy (3D‐TiO2), and Ag@3D‐TiO2 scaffolds were synthesized using electron beam melting. The antimicrobial properties of the scaffolds were examined using antibacterial tests and their cytocompatibility was assessed using a cell proliferation assay and acridine orange/ethidium bromide (AO/EB) staining. In vitro cellular assays were used to investigate the effects of the scaffold microstructural features on cell activity, proliferation, and osteogenesis‐related genes and proteins. In vivo animal experiments were used to evaluate the anti‐inflammatory and osteogenesis‐promoting abilities of the scaffolds. Results: The Ag@3D‐TiO2 scaffolds exhibited sustained anti‐microbial activity over time, enhanced cell proliferation, facilitated osteogenic differentiation, and increased extracellular matrix mineralization. In addition, alkaline phosphatase (ALP), collagen type I (COL‐I), and osteocalcin (OCN)‐related genes and proteins were upregulated. In vivo animal implantation experiments, the anti‐inflammatory effect of the Ag@3D‐TiO2 scaffolds were observed using histology, and a large amount of fibrous connective tissue was present around it; the Ag@3D‐TiO2 scaffolds were more bio‐compatible with the surrounding tissues compared with 3D‐Ti and 3D‐TiO2; a large amount of uniformly distributed neoplastic bone tissue existed in their pores, and the chronic systemic toxicity test showed that the 3D‐Ti, 3D‐TiO2, and Ag@3D‐TiO2 scaffolds are biologically safe. Conclusion: The goal of this study was to create a scaffold that exhibits antimicrobial properties and can aid bone growth, making it highly suitable for use in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Double epoxy group double quaternary ammonium salts (DEpDQAS) were synthesized by epichlorohydrin (ECH) reacting with N,N,N'N'-tetramethylethylenediamine (TMEDA) and N,N,N'N'-tetramethyl-1,6-hexanediamine (TMHDA), respectively. The results of orthogonal experiments showed that temperature and time were the key factors influencing on epoxy value and quaternarization ratio respectively. The optimal condition for higher epoxy value was the reaction temperature at 15 °C and methanol as solvent. The reaction kinetic process was determined by conductivity, which showed that the reaction had a short induction period and appeared discontinuity in progress that the reaction rate of the first stage was almost constant, while the reaction rate of the second stage decreased gradually. The product was characterized by infrared spectroscopy (FTIR) and nuclear magnetic resonance (1H NMR). The results of surface tension testing showed that DEpDQAS-6 with longer spacer chain had better surface activity and lowered the solution surface tension to 26 mN·m−1 at 25 °C and CMC 0.27 mol·L−1. The thermodynamic parameters of micellization were obtained basing on charged pseudo-phase model. The studies of cytotoxicity in vitro and antibacterial activity showed that DEpDQAS was biocompatible and its antibacterial activity was more effective against Escherichia coli than against Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

This paper discusses the current challenges and potential solutions in the field of bioprinting tissues and organs. It highlights that most bioprinted tissues are small, composed of few cell types, lack vascular systems, and have limited functionality. This paper emphasizes the need to develop methods to obtain various functional cell types, create vascular systems for nutrient delivery, and enhance the size and capabilities of 3D-printed tissue structures. Additionally, it explores the advancements in nanorobots in the medical field, focusing on their unique properties and applications in various medical areas like cancer, cardiology, and neurology. [ABSTRACT FROM AUTHOR]

Infection is a serious risk in transplant surgery and should be carefully considered while developing biomaterials. Silver nanoparticles (AgNPs) are gaining popularity due to their ability to enhance antibacterial capabilities against a wide range of bacterial types. This study sought to create two antibacterial bone regenerations by incorporating AgNPs into bovine bone particles (BBX) (Product 1) and a light cross-linked hydrogel GelMA (Product 2). Scanning electron microscopy was used to characterize the constructions. PrestoBlue™ was used to assess osteoblast and osteoclast metabolic activities on the creations. Optimized AgNP functionalized BBX and GelMA were tested in a rabbit cranial 6mm defect model to assess their regeneration ability. The presence of AgNPs appears to increase. In vitro, osteoblasts proliferated more than AgNP-free controls. It is found that a 100 jg dosage of AgNPs effectively suppresses bacteria while minimizing negative effects on bone cells. The rabbit model indicated that both BBX and GelMA hydrogels loaded with AgNPs were biocompatible, with no evidence of necrosis or inflammation. Grafts functionalized with AgNPs can defend against germs while also serving as a platform for bone cell adhesion. [ABSTRACT FROM AUTHOR]

Ideal wound dressings should show enhanced moisture management at the wound site, antibacterial and physical barrier, and mechanical robustness. Additionally, it should be easy to apply to the wound and be biocompatible and non-toxic. In this study, a linker-free freeze-thaw procedure was used to create an array of chitosan/PVA hydrogels blended with commercially available marine collagen peptides. Marine collagen peptides (CP) are easily available as by-products of the marine food industry and are an inexpensive and novel source of biomaterial in this field. The different weight ratios of chitosan, PVA, and CP influenced the hydrogel properties such as swelling, gel content, evaporation, and mechanical properties. Furthermore, SEM and ATR-FTIR were used to characterize the hydrogels generated under ideal conditions. After 24 h, the optimum hydrogel (chitosan:PVA:CP ratio of 1:5:1) showed a water absorption capacity of up to 900 %, a gel content of 80 %, and a 40 % evaporation rate. The physical interactions between marine collagen peptide and gel-forming components were validated by ATR-FTIR spectra, and the hydrogel kept a sufficient porous structure for potential wound dressing application. To test the mechanical integrity of the hydrogels, compression testing was carried out showing a compressive modulus of up to ∼40 kPa. The addition of marine collagen peptide in the chitosan/PVA hydrogel increased its wettability, antimicrobial capabilities, and hemostatic properties. Furthermore, the hydrogel preparation procedure is simple and does not use toxic chemicals, serving as a model for developing safe and effective hydrogel wound dressing.

Abstract Long‐lasting vaginal dosage forms could improve the therapeutic efficacy of vaginal microbicides, but achieving long‐term delivery to the vaginal canal has been a significant challenge. To advance understanding of vaginal dosage retention and biodistribution, we describe a method of noninvasive imaging with 89Zr‐labeled bioadhesive nanoparticles (BNPs) in non‐human primates. We additionally examined the safety of repeated BNP application. BNPs administered vaginally to cynomolgus monkeys were still detected after 24 h (1.7% retention) and 120 h (0.1% retention). BNPs did not translocate to the uterus or into systemic circulation. Analysis of inflammatory biomarkers in the vaginal fluid and plasma suggest that BNPs are safe and biocompatible, even after multiple doses. BNPs are a promising delivery vehicle for vaginally administered therapeutics. Further studies using the non‐human primate imaging materials and methods developed here could help advance clinical translation of BNPs and other long‐lasting vaginal dosage forms.