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[Display omitted] Chronic wounds affect millions of people annually and have emotional and financial implications in addition to health issues. The current treatment for chronic wounds involves the repeated use of bandages and drugs such as antibiotics over an extended period. A cost-effective and convenient solution for wound healing is the development of drug-incorporated bandages. This study aimed to develop a biocompatible bandage made of drug-incorporated poly (lactic-co-glycolic acid) (PLGA) microparticles (MPs) and eggshell membrane (ESM) for cornea wound healing. ESM has desirable properties for wound healing and can be isolated from eggshells using acetic acid or ethylenediaminetetraacetic acid (EDTA) protocols. Fluorescein isothiocyanate-labelled Bovine Serum Albumin (FITC-BSA) was used as a model drug, and the PLGA MPs were fabricated using a solvent extraction method. The MPs were successfully attached to the fibrous layer of the ESM using NaOH. The surface features of the ESM samples containing MPs were studied using a field emission scanning electron microscope (FESEM) and compared with blank ESM images. The findings indicated that the MPs were attached to the ESM fibres and had similar shapes and sizes as the control MPs. The fibre diameters of the MPs samples were assessed using Fiji-ImageJ software, and no significant changes were observed compared to the blank ESM. The surface roughness, Ra values, of the MPs incorporated ESM samples were evaluated and compared to the blank ESM, and no significant changes were found. Fourier transform infrared (FTIR) spectroscopy was used to analyse the chemical Composition of the bandage, and the spectra showed that the FBM were effectively incorporated into the ESM. The FTIR spectra identified the major peaks of the natural ESM and the PLGA polymer in the bandage. The bandage was transparent but had a reduced visibility in the waterproof test card method. The bandage achieved sustained drug release up to 10 days and was found to be biocompatible and non-toxic in a chorioallantoic membrane (CAM) assay. Overall, the drug-incorporated PLGA MPs-ESM bandage has great potential for treating chronic wounds. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Antibacterial and biodegradable polyazomethine hydrogels were successfully prepared. • To investigate usability of the hydrogels as biomaterials, water uptake capacity, drug loading or release performance, protein absorption, biodegradability and antibacterial properties were studied. • The drug loading capacity of melamine-based hydrogels was found in the range from 21.55 and 17.05 µg/mL. Abstract In the present paper, a new series of biodegradable poly(azomethine) gels were prepared to investigate the usability as biomaterials. The structures of the hydrogels were characterized by using FT-IR and SEM analyses. Contact angle measurements were also performed to investigate hydrophobicity of the hydrogels. Thermal behavior of melamine-based poly(azomethine)s and hydrogels was performed using TG-DTA and DSC techniques. Mechanical properties of poly(azomethine) hydrogels were investigated using a tensile testing method. Biodegradability, drug loading or release performance, protein absorption, water uptake and antibacterial properties were also studied due to investigate usability of melamine-based hydrogels as biomaterials. [ABSTRACT FROM AUTHOR]

In the present study, novel pH-responsive prodrug nanoparticles based on xylan-curcumin (xyl-cur) conjugate were developed to enhance the therapeutic efficacy of curcumin in cancer therapy. The synthesis of xyl-cur conjugate (prodrug) was confirmed by FT-IR, 1 H NMR, UV–vis and fluorescence spectroscopy. The xyl-cur prodrug was subsequently self-assembled in to nanoparticles (xyl-cur prodrug NPs) in an aqueous medium with the average particle size 253 nm and the zeta potential of −18.76 mV. The xyl-cur prodrug NPs were highly pH-sensitive in nature and most of the drug was released at lower pH. The interaction of the xyl-cur prodrug NPs with blood components was tested by hemolysis study. The cytotoxic activity of the xyl-cur prodrug NPs against human colon cancer cells (HT-29, HCT-15) demonstrated that the prodrug NPs exhibits greater cytotoxic effect than curcumin. Therefore, these results reveal that xyl-cur prodrug NPs could be a promising candidate for improving the intracellular delivery of curcumin in cancer therapy. [ABSTRACT FROM AUTHOR]

Multifunctional surfaces may display the potential to accelerate and promote the healing process around dental implants. However, the initial cellular biocompatibility, molecular activity, and the release of functionalized molecules from these novel surfaces require extensive investigation for clinical use. Aiming to develop and compare innovative surfaces for application in dental implants, the present study utilized titanium disks, which were treated and divided into four groups: machined (Macro); acid-etched (Micro); anodized-hydrophilic surface (TNTs); and anodized surface coated with a rifampicin-loaded polymeric layer (poly(lactide-co-glycolide), PLGA) (TNTsRIMP). The samples were characterized regarding their physicochemical properties and the cumulative release of rifampicin (RIMP), investigated at different pH values. Additionally, differentiated osteoblasts from mesenchymal cells were used for cell viability and qRT-PCR analysis. Antibacterial properties of each surface treatment were investigated against Staphylococcus epidermidis. TNTsRIMP demonstrated controlled drug release for up to 7 days in neutral pH environments. Osteogenic cell cultures indicated that all the evaluated surfaces showed biocompatibility. The TNTs group revealed up-regulated values for bone-related gene quantification in 7 days, followed by the TNTsRIMP group. Furthermore, the antibiotic-functionalized surface revealed effectiveness to inhibit S. epidermidis and stimulate promising conditions for osteogenic cell behavior. Characteristics such as nanomorphology and hydrophilicity were determinants for the up-regulated quantification of osteogenic biomarkers related to early bone maturation, encouraging application in intra-osseous implant surfaces; in addition, antibiotic-functionalized surfaces demonstrated significant higher antibacterial properties compared to the other groups. Our findings suggest that polymeric-antibiotic-loaded coating might be applied for the prevention of early infections, favoring its application in multifunctional surfaces for intra- and/or trans-mucosal components of dental implants, while, hydrophilic nanotextured surfaces promoted optimistic properties to stimulate early bone-related cell responses, favoring its application in bone-anchored surfaces. [Display omitted] • Macro-, micro-, and nano-topographies were developed for application on dental implant surfaces. • An antibiotic-release coating demonstrated biocompatibility and successful antibacterial properties. • Hydrophilic nanotextured surfaces showed optimistic properties for intra-osseous surfaces. • The drug-release coating revealed promising properties to defend against early contamination in the trans-mucosal region. • Particular combinations of surface properties may perform favorable actions on different regions of dental implants. [ABSTRACT FROM AUTHOR]

Bioactive titania (TiO 2 ) microparticles can be used as drug-releasing cement fillers for the chemotherapeutic treatment of metastatic bone tumors. Porous anatase-type TiO 2 microspheres around 15 μm in diameter were obtained through a sol–gel process involving a water-in-oil emulsion with 30:70 SiO 2 /H 2 O weight ratio and subsequent NaOH solution treatment. The water phase consisted of methanol, titanium tetraisopropoxide, diethanolamine, SiO 2 nanoparticles, and H 2 O, while the oil phase consisted of kerosene, Span 80, and Span 60. The resulting microspheres had a high specific surface area of 111.7 m 2 ·g − 1 . Apatite with a network-like surface structure formed on the surface of the microspheres within 8 days in simulated body fluid. The good apatite-forming ability of the microspheres is attributed to their porous structure and the negative zeta potential of TiO 2 . The release of rhodamine B, a model for a hydrophilic drug, was rapid for the first 6 h of soaking, but diffusion-controlled thereafter. The burst release in the first 6 h is problematic for clinical applications; nonetheless, the present results highlight the potential of porous TiO 2 microspheres as drug-releasing cement fillers able to form apatite. [ABSTRACT FROM AUTHOR]

Abstract: It is desired that the coatings on metallic implants have both excellent biological responses and good loading-release capacities of biological factors or drugs. So far, the challenge still remains, because the morphology and composition of the bioactive coatings are usually not favorable for accommodating drug molecules. In this study, we adopted an approach of incorporating chitosan nanospheres into a thin mineralized collagen coating; this approach is based on the good loading–release behavior of the nanospheres and the good cytocompatibility of the thin coating. The incorporation of chitosan nanospheres into the mineralized collagen coatings was realized by electrolytic co-deposition. The morphologies and microstructures of the resulting coatings were characterized by SEM, and the phase and chemical compositions of the coatings were measured by XRD and FTIR. The loading–release capacity for vancomycin hydrochloride (VH) was determined by ultraviolet spectrophotometry. MTS assay was used to evaluate cytocompatibility, and in vitro bacterial adhesion was tested for assessing the antibacterial effects of the VH-loaded coatings. The chitosan nanospheres adhered tightly to collagen fibrils. The incorporated coatings facilitated the sustained release of VH, and had a clear antibacterial effect. The incorporation of chitosan nanospheres into mineralized collagen coatings demonstrates an effective way to improve the drug loading–release capacity for the thin coatings. This formulation had a highly effective biological response. [Copyright &y& Elsevier]

Abstract: Multifunctional hydrogels that simultaneously possess semi-interpenetrating networks structure, strong photoluminescence, and temperature sensitivity were successfully fabricated based on the crosslink of poly(acrylamide) (PAAm) in the presence of poly(N-isopropylacrylamide) (PNIPAM) and CdTe quantum dots (QDs) at a mild condition. With the increase of external temperature, the photoluminescence (PL) intensity and emission peak of the hydrogels gradually decreased and red-shifted, respectively. Decreasing the temperature, the PL intensity and emission peak of the hydrogels could back to their initial values again. Moreover, drug-release experiments on the multifunctional hydrogels demonstrated that the release rate can be tuned by the environmental temperature and the content of PNIPAM. In addition, biocompatible hyperbranched polyglycerol functionalized QDs (QD@HPGs) instead of pristine QDs can also be incorporated into the hydrogels, affording biocompatible hydrogels which could still exhibit temperature-sensitive photoluminescence and drug-release behaviors. [Copyright &y& Elsevier]

The application of iontophoresis was demonstrated in the nail drug delivery of terbinafine (TH) recently. This study explored a systematic assessment of this approach to enhance the drug delivery using a novel topical formulation, and the subsequent release of TH from the drug loaded nails. For the first time, a nail on-agar plate model was used to study the release of drug from the iontophoresis (0.5 mA/cm2) loaded nails. In addition, the activity of the drug released from the drug loaded nail plate was studied against Trichophyton rubrum. An increase in applied current density and current duration enhanced the transport of TH into and through the nail plate. In vitro release of drug from the iontophoretic loaded nails into agar plates exhibited 2-phase release pattern. The amount of drug released in both of the in vitro models was comparable, and the nails loaded using iontophoresis continued to release levels of TH > 2 orders of magnitude above the minimum inhibitory concentration over at least 52 days. Results indicate that iontophoresis enhances the delivery of terbinafine into and through the nail plate and suggest that the use of this treatment approach could result in a safe and more efficacious outcome with less frequent treatments. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4130–4140, 2009 [ABSTRACT FROM AUTHOR]

• The gelation process of TOCN and TOChN was optimized that improved the production efficiency. • The release of amygdalin from hydrogel could be more than 60 h with a release amount of 80 %. • The release capacity of hydrogels showed diversity due to the different pH surroundings. Cellulose and chitin, as the two important natural carbohydrate polymers, have possibility to disassemble to biomass derived polysaccharide nanofibers. The 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) oxidized nanocellulose and nanochitin based hydrogel was fabricated via acid gas phase coagulation. It was observed that hydrogels began to form when the pH was lower than 3. When 0.1 mL of acetic acid coagulation bath was provided, 10 h were enough to form sufficient physical crosslinking. Moreover, the release time of amygdalin loaded in the hydrogel could be more than 60 h with a release amount of 80 % due to the uniform network and water-bearing structure. Meanwhile, the release capacity of hydrogels showed diversity at different pH surroundings, which was attributed to the existence of carboxyl groups on the oxidized nanofiber. The results suggested the possible application of the produced nanofiber hydrogels in some specific areas, such as drug delivery, wound dressing, and food packaging. [ABSTRACT FROM AUTHOR]

• A novel amphipathic triblock copolymer side-chain containing aldehyde and ferrocene groups was prepared via ROMP. • DOX could be grafted to the side chain of triblock copolymer via Schiff base linkage. • DOX-grafting triblock copolymer can self-assemble into micelles to encapsulate Rhodamine B. • Rhodamine B and DOX could be stepwise released under the treatment of oxidation and acid in turn. • In vitro and in vivo experimental results confirm the good biocompatibility of the triblock copolymer. Using the ring-opening metathesis polymerization, a new amphipathic triblock polynorbornene-based copolymer containing reactive aldehyde, redox-active ferrocene, and dendritic oligoethylene glycols units (PNCHO-PNFc-PNTEG), was controllably synthesized and exhibited the dual-cargo loading capacity with the oxidation/pH stimuli-responsive behavior. PNCHO-PNFc-PNTEG could conjugate the amino-containing doxorubicin (DOX) by the acid-sensitive Schiff base reaction. The DOX-grafted PNCHO-PNFc-PNTEG could further self-assemble into spherical nanoscale polymeric micelles that can encapsulate the second model cargo rhodamine B (RhB). The step-by-step release behavior of the loaded two cargos was observed. Namely, the loaded RhB could be firstly released under the stimulus of oxidant, and the grafted DOX could be then released under acidic condition. Moreover, PNCHO-PNFc-PNTEG micelles showed excellent biocompatibility both in in vitro L929 cell test and in vivo zebrafish embryo toxicity experiments. Thus, PNCHO-PNFc-PNTEG as polymeric carrier has great application potential in the medical field for controllable drug release. [ABSTRACT FROM AUTHOR]

Novel antibacterial and drug-release dual-function membranes based on the cross-linked hyperbranched cationic polymers (c-HCPM) were synthesized by cross-linkage of hyperbranched poly(4-chloromethylstyrene) (PVBC) followed by quaternary amination or quaternary phosphonium salinization. The resulting c-HCPMs have a good hydrophilicity and swelling ability and show excellent broad-spectrum antibacterial and anti-bacterial adhesion properties against gram negative Escherichia coli and gram positive Staphylococcus aureus. Meanwhile, curcumin, a medicine that can promote wound healing, was successfully loaded in the c-HCPM membranes. The curcumin release performance of the c-HCPM membranes was investigated by an in vitro drug release experiment. The curcumin loaded c-HCPMs exhibited a significant performance of controlled curcumin release. These results suggest that the dual-function of antibacterial and controlled drug-release were successfully realized by the c-HCPMs. The hyperbranched structure of PVBC having abundant terminal cations and intramolecular cavities was postulated to afford c-HCPMs the excellent antibacterial and controlled drug release performances. In this study, the influences of the kind and substituent of the cations in the membrane on the antibacterial and drug release performances of c-HCPMs were systematically investigated. In addition, hemcompatibility and cytotoxicity studies were performed on c-HCPMs, the results indicate that c-HCPMs have good biocompatibility and can be used as a potential antibacterial dressing for wounds. The curcumin loaded c-HCPM can be a potential wound dressing material that has the dual function of anti-bacterial infection and promoting wound healing. Unlabelled Image • Novel crosslinked hyperbranched cationic polymer membranes (c-HCPMs) were prepared. • The c-HCPMs show excellent broad-spectrum antibacterial properties. • The drug loaded c-HCPMs exhibited a good performance of controlled drug release. • The cations and cavities in the hyperbranched structure cause the dual-function. [ABSTRACT FROM AUTHOR]