NIR responsive scaffold with multistep shape memory and photothermal-chemodynamic properties for complex tissue defects repair and antibacterial therapy.

Complex tissue damage accompanying with bacterial infection challenges healthcare systems globally. Conventional tissue engineering scaffolds normally generate secondary implantation trauma, mismatched regeneration and infection risks. Herein, we developed an easily implanted scaffold with multistep shape memory and photothermal-chemodynamic properties to exactly match repair requirements of each part from the tissue defect by adjusting its morphology as needed meanwhile inhibiting bacterial infection on demand. Specifically, a thermal-induced shape memory scaffold was prepared using hydroxyethyl methacrylate and polyethylene glycol diacrylate, which was further combined with the photothermal agent iron tannate (FeTA) to produce NIR light-induced shape memory property. By varying ingredients ratios in each segment, this scaffold could perform a stepwise recovery under different NIR periods. This process facilitated implantation after shape fixing to avoid trauma caused by conventional methods and gradually filled irregular defects under NIR to perform suitable tissue regeneration. Moreover, FeTA also catalyzed Fenton reaction at bacterial infections with abundant H2O2, which produced excess ROS for chemodynamic antibacterial therapy. As expected, bacteriostatic rate was further enhanced by additional photothermal therapy under NIR. The in vitro and vivo results showed that our scaffold was able to perform high efficacy in both antibiosis, inflammation reduction and wound healing acceleration, indicating a promising candidate for the regeneration of complex tissue damage with bacterial infection.

A low-swelling alginate hydrogel with antibacterial hemostatic and radical scavenging properties for open wound healing.

Development of a low-cost and biocompatible hydrogel dressing with antimicrobial, antioxidant, and low swelling properties is important for accelerating wound healing. Here, a multifunctional alginate hydrogel dressing was fabricated using the D-(+)-gluconic acidδ-lactone/CaCO3system. The addition of hyaluronic acid and tannic acid (TA) provides the alginate hydrogel with anti-reactive oxygen species (ROS), hemostatic, and pro-wound healing properties. Notably, soaking the alginate hydrogel in a poly-ϵ-lysine (EPL) aqueous solution enables the alginate hydrogel to be di-crosslinked with EPL through electrostatic interactions, forming a dense network resembling 'armor' on the surface. This simple one-step soaking strategy provides the alginate hydrogel with antibacterial and anti-swelling properties. Swelling tests demonstrated that the cross-sectional area of the fully swollen multifunctional alginate hydrogel was only 1.3 times its initial size, thus preventing excessive wound expansion caused by excessive swelling. After 5 h ofin vitrorelease, only 7% of TA was cumulatively released, indicating a distinctly slow-release behavior. Furthermore, as evidenced by the removal of 2,2-diphenyl-1-picrylhydrazyl free radicals, this integrated alginate hydrogel systems demonstrate a notable capacity to eliminate ROS. Full-thickness skin wound repair experiment and histological analysis of the healing site in mice demonstrate that the developed multifunctional alginate hydrogels have a prominent effect on extracellular matrix formation and promotion of wound closure. Overall, this study introduces a cost-effective and convenient multifunctional hydrogel dressing with high potential for clinical application in treating open wounds.

First Insight into Lignin Valorization as a Promising Biopolymer for the Modulation of the Physicochemical Properties of Port Wine.

Lignosulfonate (LS), kraft lignin (KL), and organosolv lignin (OL) were evaluated as potential modulating agents of the physicochemical properties of Port wine at two different concentrations for 7 and 30 days. KL and LS demonstrated the ability to remove proteins and potentiate the anthocyanin concentration. LS reduced the tannin content and the interaction of salivary acidic proline-rich proteins with wine phenolic compounds. None of the lignin promoted a perceptible color change; however, the yellowish color of KL and OL at 100 g/hL contributed to an increase in the yellow tones of wines. Lignin improved wine aroma by reducing the amount of unwanted volatiles by 30% and increasing the content of ethyl esters associated with fruity aromas by up to 60%. The results suggest that lignin, especially LS, can be employed as a modulating agent, positively impacting wine's physicochemical properties. This valorization of a byproduct opens up new opportunities for the wine industry.

TME-Responsive Nanoplatform with Glutathione Depletion for Enhanced Tumor-Specific Mild Photothermal/Gene/Ferroptosis Synergistic Therapy.

Background: Triple negative breast cancer (TNBC) is one of the worst prognosis types of breast cancer that urgently needs effective therapy methods. However, cancer is a complicated disease that usually requires multiple treatment modalities. Methods: A tumor microenvironment (TME)-responsive PFC/TRIM37@Fe-TA@HA (abbreviated as PTFTH) nanoplatform was constructed by coating Fe3+ and tannic acid (TA) on the surface of TRIM37-siRNA loaded phase-transition perfluorocarbon (PFC) nanodroplets and further modifying them with hyaluronic acid (HA) to achieve tumor-specific mild photothermal/gene/ferroptosis synergistic therapy (MPTT/GT/ Ferroptosis) in vitro. Once internalized into tumor cells through CD44 receptor-mediated active targeting, the HA shell of PTFTH would be preliminarily disassembled by hyaluronidase (HAase) to expose the Fe-TA metal-phenolic networks (MPNs), which would further degrade in response to an acidic lysosomal environment, leading to HAase/pH dual-responsive release of Fe3+ and PFC/TRIM37. Results: PTFTH showed good biocompatibility in vitro. On the one hand, the released Fe3+ could deplete the overexpressed glutathione (GSH) through redox reactions and produce Fe2+, which in turn converts endogenous H2O2 into highly cytotoxic hydroxyl radicals (•OH) for chemodynamic therapy (CDT). On the other hand, the local hyperthermia generated by PTFTH under 808 nm laser irradiation could not only improve CDT efficacy through accelerating the Fe2+-mediated Fenton reaction, but also enhance TRIM37-siRNA delivery for gene therapy (GT). The consumption of GSH and accumulation of •OH synergistically augmented intracellular oxidative stress, resulting in substantial tumor cell ferroptosis. Moreover, PTFTH possessed outstanding contrast enhanced ultrasound (CEUS), photoacoustic imaging (PAI) and magnetic resonance imaging (MRI) ability. Conclusion: This PTFTH based multiple-mode therapeutic strategy has successfully achieved a synergistic anticancer effect in vitro and has the potential to be translated into clinical application for tumor therapy in future.

Modified Chitosan-Based Coating/Packaging Composites with Enhanced Antibacterial, Antioxidant, and UV-Resistant Properties for Fresh Food Preservation.

Chitosan-based biomass packaging materials are a promising material for food preservation, but their limited solubility, antioxidant capacity, UV resistance, and mechanical properties severely restrict their application. In this study, we developed a novel chitosan-based coating/packaging composite (QCTO) using quaternary ammonium salt and tannic acid (TA)-modified chitosan (QCS-TA) and oxidized chitosan (OCS). The introduction of quaternary ammonium salt and TA effectively improves the water solubility and antibacterial, antioxidant, and UV-resistant properties of chitosan. The Schiff-base bond formed between OCS and QCS-TA, along with the TA-mediated multiple interactions, conferred the prepared composite film with good mechanical properties (69.9 MPa tensile strength) and gas barrier performance to water (14.3 g·h-1·m-2) and oxygen (3.5 g·mm·m-2·h-1). Meanwhile, the prepared QCTO composites demonstrate excellent biocompatibility and safety and are applied as coatings for strawberries and bananas as well as packaging films for mushrooms. These preservation experiments demonstrated that the prepared composites are able to effectively reduce weight loss, prevent microbial growth, maintain color, and significantly prolong the shelf life of fresh products (bananas, strawberries, and mushrooms extended shelf life by 6, 5, and 6 days, respectively). Therefore, the developed QCTO coating/packaging film shows great potential for applications in the field of food preservation and packaging.

Controlled preparation of tannic acid-derived carbonized dots and their use to inhibit amyloid aggregation and promote aggregate disaggregation.

Tannic acid (TA)-derived carbon dots (TACDs) were synthesized for the first time via a solvothermal method using TA as one of the raw materials, which may effectively inhibit amyloid fibril aggregation and disaggregate mature fibril. The fluorescent property of TACDs were modulated by adjusting the ratio of TA to o-phenylenediamine (oPD), and TACDs fabricated with the precursor ratio as 1:1 showed the best fluorescent property. Circular dichroism spectra (CD) showed that the structure of ß-sheet decreased as the concentration of TACDs increased. The inhibition efficiency, as confirmed by thioflavin T (ThT) and transmission electron microscopy (TEM), is extraordinary at 98.16%, whereas disaggregation efficiency is noteworthy at 97.97%, and the disaggregated lysozyme fibrils did not reaggregate after 7 days. More critically, TACDs can also alleviate the cellular toxicity caused by Aß fibrils and improve cell viability. This work offers a new perspective on the design of scavengers for amyloid plaques.

The influence mechanism of pH and polyphenol structures on the formation, structure, and digestibility of pea starch-polyphenol complexes via high-pressure homogenization.

The formation of starch-polyphenol complexes through high-pressure homogenization (HPH) is a promising method to reduce starch digestibility and control postprandial glycemic responses. This study investigated the combined effect of pH (5, 7, 9) and polyphenol structures (gallic acid, ferulic acid, quercetin, and tannic acid) on the formation, muti-scale structure, physicochemical properties, and digestibility of pea starch (PS)-polyphenol complexes prepared by HPH. Results revealed that reducing pH from 9 to 5 significantly strengthened the non-covalent binding between polyphenols and PS, achieving a maximum complex index of 13.89 %. This led to the formation of complexes with higher crystallinity and denser structures, promoting a robust network post-gelatinization with superior viscoelastic and thermal properties. These complexes showed increased resistance to enzymatic digestion, with the content of resistant starch increasing from 28.66 % to 42.00 %, rapidly digestible starch decreasing from 42.82 % to 21.88 %, and slowly digestible starch reducing from 71.34 % to 58.00 %. Gallic acid formed the strongest hydrogen bonds with PS, especially at pH 5, leading to the highest enzymatic resistance in PS-gallic acid complexes, with the content of resistant starch of 42.00 %, rapidly digestible starch of 23.35 % and slowly digestible starch of 58.00 %, and starch digestion rates at two digestive stages of 1.82 × 10-2 min-1 and 0.34 × 10-2 min-1. These insights advance our understanding of starch-polyphenol interactions and support the development of functional food products to improve metabolic health by mitigating rapid glucose release.

HPLC METHOD FOR THE QUANTIFICATION OF SOME ACTIVE FLAVONOIDS IN ETHYL ACETATE EXTRACT OF LEAVES OF BUTEA MONOSPERMA LINN.

AIM: The aim of the present investigation is to study HPLC process to evaluate Some Active Flavonoids in Ethyl Acetate Extract of Leaves of Butea monosperma Linn. MATERIAL AND METHODS: Using a soxhlation device, the leaves of Butea monosperma Linn. were extracted in stages. Each powdered batch (500g) was extracted in stages with polarity-graded solvents such as petroleum ether (Pet. Et) (60-80º), chloroform (CHCl3), ethyl acetate (EtOAc) using a soxhlet extractor. Alkaloids, flavonoids, glycosides, tannins, phenols, and steroids, among other chemical families of components, were identified through qualitative phytochemical screenings of each extract. To make a 10 g/ml stock, standard phenolic markers like quercetin, rutin, catechin, gallic acid, and chlorogenic acid were dissolved in methanol. Phytoconstituents were separated and identified from extracts using various solvents and combinations of solvents, which were chosen after consulting the literature. RESULTS AND DISCUSSION: Preliminary phytochemical screening showed the revealed that the leaves contain steroid, triterpenoids, fatty acid and alkaloids. While the ethyl acetate extract found to contain therapeutically important phytoconstitutes such as steroids, triterpenoids, saponins, flavonoids, and tannins. Bioactive extracts of Butea monosperma were found to include flavonoids and phenolic substances. In ethyl acetate extract, various flavonoids and phenolic compounds were discovered. CONCLUSION: This is a preliminary report on the identification of phytochemical and HPLC evaluation of ethyl acetate extract of leaves of Butea monosperma Linn. and to unravel the mechanisms driving bioactive qualities and the existence of putative synergy among these substances, more research is needed on the isolation and characterization of individual Flavonoids or phenolic compounds.

Tannic acid elicits differential gene regulation in prostate cancer apoptosis.

Prostate cancer is a significant global health concern that requires innovative therapeutic investigations. Here, the potential anticancer properties of tannic acid were evaluated by examining its effects on apoptosis in prostate cancer cell lines. PC-3 and LnCaP prostate adeno carcinoma cells, along with PNT1A prostate control cells, were cultured and divided into untreated and tannic acid-treated groups. Cell proliferation, cytotoxicity, and effects of tannic acid on the cell death mechanism were evaluated. mRNA expression levels of 84 genes were explored in cells following tannic acid treatment. Notably, tannic acid-induced down-regulation of several pro-survival genes, including ATM, BCL2, BCL2A1, BIK, BIRC2, BIRC3, BRE, CASP3, CASP6, CASP8, CHEK2, CRADD, PPIA, RPA3, TNFSF18, TRAF1, TRAF2, TRAF4, and TRAF5 in both cell lines. Moreover, tannic acid treatment led to the up-regulation of various pro-apoptotic genes, such as BCL10, BIRC3, BNIP3, CASP1, CASP5, CD40, CIDEB, DAPK2, FASLG, GADD45A, MYD88, RPA 3, TNFRSF10D, TNFRSF17, TNFRSF8, TNFSF13B, TNFSF4, TNFSF7, TNFSF8, TNFSF9, TP53, TRAF1, and TRAF2 in both PC-3 and LnCap cells. These findings highlight tannic acid's ability to induce apoptosis in prostate cancer cells through pro-apoptotic pathways. This study concludes that tannic acid selectively inhibits prostate cancer cell growth.

Fabrication and Application of Tannin Double Quaternary Ammonium Salt/Polyvinyl Alcohol as Efficient Sterilization and Preservation Material for Food Packaging.

Food packaging films play a vital role in preserving and protecting food. The focus has gradually shifted to safety and sustainability in the preparation of functional food packaging materials. In this study, a bisquaternary ammonium salt of tannic acid (BQTA) was synthesized, and the bioplastics based on BQTA and polyvinyl alcohol (PVA) were created for packaging applications. The impact of BQTA on antibacterial effect, antioxidant capacity, opacity, ultraviolet (UV) protective activity, mechanical strength, thermal stability, and anti-fog of the resultant bioplastics was examined. In vitro antibacterial experiments confirmed that BQTA possesses excellent antimicrobial properties, and only a trace amount addition of BQTA in PVA composite film could inhibit about 100% of Escherichia coli and Staphylococcus aureus. Compared to BQTA/PVA bioplastics with pure PVA, the experiment findings demonstrate that BQTA/PVA bioplastics show strong antioxidant and UV protection action and the performance of fruit preservation. It also revealed a small improvement in thermal stability and tensile strength. The small water contact angle, even at low BQTA concentrations, gave BQTA/PVA bioplastics good anti-fog performance. Based on the findings, bioplastics of BQTA/PVA have the potential to be used to create packaging, and they can be applied as the second (inner) layer of the primary packaging to protect food freshness and nutrition due to their antioxidant activity and biocompatibility.

Synergetic effect of Accentuated Cut Edges (ACE) and macerating enzymes on the phenolic composition of Marquette red wines.

One of the challenges of cold-hardy grape cultivars is their typical low content of tannins, alongside the presence of anthocyanin diglucoside and high acidity, which can lead to unbalanced red wines. This study hypothesized that the combination of Accentuated Cut Edges (ACE) and macerating enzymes would improve phenolics extraction from grape skins after disruption. The effects of those two winemaking techniques, either used separately or together, on red wine quality characteristics were investigated at crushing, bottling, and after six or nine months of aging. Overall, the combination of treatments improved the concentration of monomeric phenolics (20 %) and tannins (21 %) after nine months of aging. ACE or enzyme treatment separately applied had little impact on phenolics extraction in finished wines. This study exhibited a potential strategy to modify phenolics profile through the synergistic effect of ACE and macerating enzymes by causing cellular breakdown in a cold-hardy red grape cultivar.

The role of TRPA1 and TRPV1 in the perception of astringency.

Astringency, commonly described as a drying, roughening, and/or puckering sensation associated with polyphenol-rich foods affects their palatability. While the compounds eliciting astringency are known, its mechanism of action is debated. This study investigated the role of transient receptor potential (TRP) channels A1 and V1 in astringency perception. If TRP A1 or V1 have a functional role in astringency perception, then desensitizing these receptors should decrease perceived astringency. Thirty-seven panelists underwent unilateral lingual desensitization of TRP A1 and V1 channels using mustard oil and capsaicin, respectively. Panelists then evaluated four astringent stimuli: epicatechin (EC), epigallocatechin gallate (EGCG), tannic acid (TA), and potassium alum (Alum), via 2-AFC and intensity ratings. When TRPA1 receptors were desensitized on one half of the tongue via mustard oil, no significant differences were observed between the treated and untreated sides for both 2-AFC and intensity ratings. Similarly, when TRPV1 receptors were desensitized on one half of the tongue via capsaicin, no significant differences were observed between the treated and untreated sides for both 2-AFC and intensity ratings. These findings challenge the notion that TRP channels play a pivotal role in astringency perception.

Natural redox mediator anthraquinone aloe-emodin facilitated the in-situ mineralized γ-FeO(OH) membrane for the removal of tannic acid through photocatalytic-PMS activation.

The growing utilization of Traditional Chinese Medicine (TCM) has resulted in an increase in wastewater. Herein, a new kind of organic-inorganic redox mediator membrane by immobilizing γ-FeO(OH) and aloe-emodin(AE) with the characteristic large π-conjugation anthraquinone structure on PVDF membrane was innovatively achieved. AE exhibiting both electron deficiency and redox activity possesses a co-catalyst role in degradation of tannic acid (TA), aiding in the separation of charge carriers through the sequential hydrogenation and dehydrogenation of AE. The removal rates of TA were 92.8 % in the tannic acid solution and 60.3 % in the simulated rhubarb wastewater by the AE-γ-FeO(OH) membrane under PMS+Vis conditions in 45 min. Also, they show a higher recovery of pure water flux and owning good fouling performance. Overall, this current work presents a novel approach for the design and preparation of organic-inorganic photocatalytic composite membrane using readily available natural products for the purification TCM wastewater.

Tannic acid protects neuroblastoma cells against hydrogen peroxide - triggered oxidative stress by suppressing oxidative stress and apoptosis.

Recent investigations indicate that tannic acid is associated with a decrease in oxidative damage. Growing evidence supports the protective effects of tannic acid on the central nervous system (CNS). However, uncertainties persist regarding its influence on hydrogen peroxide (H2O2)-triggered oxidative impairment in nerve cells and its interaction with apoptosis. Hence, the objective of this work was to examine the neuroprotective impact of tannic acid on SH-SY5Y cell impairment following H2O2-induced oxidative stress, particularly concerning apoptotic pathways. The control group received no treatment, while the H2O2 group underwent treatment with 0.5 mM H2O2 for a duration of 24 h. The tannic acid group received treatment with different concentrations of tannic acid for a duration of 24 h. Meanwhile, the tannic acid + H2O2 group underwent pre-treatment with tannic acid for one hour and was subsequently subjected to 0.5 mM H2O2 for one day. Within the tannic acid + H2O2 group, the cell viability in SH-SY5Y cells was notably enhanced by tannic acid at concentrations of 2.5, 5, and 10 µM. It also resulted in a considerable rise in TAS (Total Antioxidant Status) levels and a concurrent decline in TOS (Total Oxidant Status) levels, serving as indicators of reduced oxidative stress. Additionally, tannic acid treatment resulted in decreased levels of apoptotic markers (Bax, cleaved PARP, and cleaved caspase 3) and oxidative DNA damage marker (8-oxo-dG), while increasing the anti-apoptotic marker Bcl-2. The findings from flow cytometry also revealed a significant reduction in the apoptosis rate following pretreatment with tannic acid. In summary, tannic acid demonstrates protective effects on SH-SY5Y cells in the face of H2O2-triggered oxidative damage by suppressing both oxidative stress and apoptosis. Nevertheless, additional research is warranted to assess the neuroprotective potential of tannic acid.

A double-layer film based on the strategy of tannic acid-anthocyanin co-pigmentation and tannic-crosslinked-gelatin/-reduced Ag nanoparticles for beef preservation and monitoring.

A double-layer film was developed with tannic acid (TA) co-pigmented purple potato anthocyanin extract (PAE)-agar as the inner layer, and K-carrageenan-oregano essential oil Pickering emulsion (OPE)/silver nanoparticles (TA-AgNPs) as the outer layer. Molecular docking and FT-IR results elucidated that intermolecular hydrogen bond was the main interaction between components in the agar-carrageenan matrix, with TA and PAE contributing to intensified anthocyanin color through π-π stacking. The incorporation of OPE/TA-AgNPs enhanced the film's hydrophobicity (WCA > 100°) and UV-vis barrier (close to 0% at 200-320 nm, effectively impeding UVA, UVB, and UVC) properties and exhibited outstanding antioxidant (DPPH scavenging rate > 88%) and antimicrobial activities. This film showed a significant color change in the pH range of 2-12 (from pink to yellow) and a considerable sensitivity to volatile amines within 2 min. The films effectively alleviated beef spoilage (extending the shelf life of beef for 1d) and reflected the freshness of beef during storage. Additionally, the digital color information of the film was obtained by a smartphone combined with RGB values analysis to quantify the freshness of beef rapidly. Therefore, this study expands the application of food packaging films with freshness preservation and monitoring in the field of animal-derived food.

A water-resistant egg white/chitosan/pectin blending film with spherical-linear molecular interpenetrating network strengthened by multifunctional tannin-nisin nanoparticles.

Edible films are effective alternatives to plastic packaging, however, the hydrophilicity of edible films based on protein and polysaccharide limits the application. Therefore, we fabricated a water-stable hybrid film with a linear-spherical interpenetrating molecular topology network using egg white (EW), chitosan (CS), and pectin. Meanwhile, the nisin-tannin acid self-assembly complex nanoparticles were employed as a multifunctional cross-linker, antibacterial and antioxidant agent to improve the performance of films. The FTIR, XRD, and SEM analysis revealed that the conformation and crystalline structure rearrangement of chitosan induced by the alkaline environment provided by egg white enhanced the network structure of films, effectively avoided the addition of modifying reagents. The proposed hybrid films exhibited excellent properties, with EW/TNPCS3 showing the best overall performance. The water contact angle (WCA) increased to 105.27 ± 1.62°, and its dissolution and swelling rates were significantly lower than pure egg white and pure chitosan films. Moreover, tannin-nisin (TN) nanoparticles endowed the films with excellent antimicrobial activity against the common Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. Thus, the prepared blending films have great application potential in food preservation, especially to maintain stable performance in high humidity environment.

Development of a multifunctional active food packaging membrane based on electrospun polyvinyl alcohol/chitosan for preservation of fruits.

To mitigate environmental impacts in food preservation, the development of a multifunctional membrane for packaging is of importance. In this study, we have successfully fabricated a nanofibrous membrane using an eco-friendly electrospinning technique, comprising polyvinyl alcohol (PVA), chitosan (CS), and tannic acid (TA). The resulting nanofibrous membranes were crosslinked with glutaraldehyde (GA) and surface modified with ZnO. Our findings demonstrate that the crosslinking process enhances water resistance, reduces water vapor permeability, improves tensile strength (from 3 to 18 MPa), and enhances thermal stability (increasing decomposition temperature from 225 °C to 310 °C). Furthermore, the incorporation of TA and ZnO provides antioxidant properties to the membrane, effectively preventing food decomposition caused by UV-induced oxidation. Additionally, CS, TA, and ZnO synergistically exhibit a remarkable antibacterial effect with a bacteriostasis rate exceeding 99.9 %. The strawberry fresh-keeping experiment further confirms that our developed membrane significantly extends shelf life by up to 6 days. Moreover, cytotoxicity assays confirm the non-toxic nature of these membranes. The innovative significance of this study lies in proposing a robust GA-PVA/CS/TA@ZnO nanofibrous membrane with excellent mechanical properties, biocompatibility, and multiple functionalities including antibacterial, anti-ultraviolet, and anti-oxidation capabilities. It has tremendous potential for applications in active food packaging materials.

Copper-MOF and tannic acid-empowered composite cryogel as a skin substitute for accelerated deep wound healing.

The effective management of deep skin wounds remains a significant healthcare challenge that often deteriorates with bacterial infection, oxidative stress, tissue necrosis, and excessive production of wound exudate. Current medical approaches, including traditional wound dressing materials, cannot effectively address these issues. There is a great need to engineer advanced and multifunctional wound dressings to address this multifaceted problem effectively. Herein, a rationally designed composite cryogel composed of a Copper Metal-Organic Framework (Cu-MOF), tannic acid (TA), polyvinyl alcohol (PVA), and zein protein has been developed by freeze-thaw technique. Cryogels display a remarkable swelling capacity attributed to their interconnected microporous morphology. Moreover, dynamic mechanical behaviour with the characteristics of potent antimicrobial, antioxidant, and biodegradation makes it a desirable wound dressing material. It was further confirmed that the material is highly biocompatible and can release TA and copper ions in a controlled manner. In-vivo skin irritation in a rat model demonstrated that composite cryogel did not provoke any irritation/inflammation when applied to the skin of a healthy recipient. In a deep wound model, the composite cryogel significantly accelerates the wound healing rate. These findings highlight the multifunctional nature of composite cryogels and their promising potential for clinical applications as advanced wound dressings.

Layer-by-layer self-assembly coatings on strontium titanate nanotubes with antimicrobial and anti-inflammatory properties to prevent implant-related infections.

One way to effectively address endophyte infection and loosening is the creation of multifunctional coatings that combine anti-inflammatory, antibacterial, and vascularized osteogenesis. This study started with the preparation of strontium-doped titanium dioxide nanotubes (STN) on the titanium surface. Next, tannic acid (TA), gentamicin sulfate (GS), and pluronic F127 (PF127) were successfully loaded into the STN via layer-by-layer self-assembly, resulting in the STN@TA-GS/PF composite coatings. The findings demonstrated the excellent hydrophilicity and bioactivity of the STN@TA-GS/PF coating. STN@TA-GS/PF inhibited E. coli and S. aureus in vitro to a degree of roughly 80.95 % and 92.45 %, respectively. Cellular investigations revealed that on the STN@TA-GS/PF surface, the immune-system-related RAW264.7, the vasculogenic HUVEC, and the osteogenic MC3T3-E1 showed good adhesion and proliferation activities. STN@TA-GS/PF may influence RAW264.7 polarization toward the M2-type and encourage MC3T3-E1 differentiation toward osteogenesis at the molecular level. Meanwhile, the STN@TA-GS/PF coating achieved effective removal of ROS within HUVEC and significantly promoted angiogenesis. In both infected and non-infected bone defect models, the STN@TA-GS/PF material demonstrated strong anti-inflammatory, antibacterial, and vascularization-promoting osteogenesis properties. In addition, STN@TA-GS/PF had good hemocompatibility and biosafety. The three-step process used in this study to modify the titanium surface for several purposes gave rise to a novel concept for the clinical design of antimicrobial coatings with immunomodulatory properties.

Quaternary ammonium grafted chitosan hydrogel with enhanced antibacterial performance as tannin acid and deferoxamine carrier to promote diabetic wound healing.

The delay of diabetic wound healing puts a huge burden on the society. The key factors hindering wound healing include bacterial infection, unresolved inflammation and poorly generated blood vessels. In this paper, glycidyl trimethyl ammonium chloride (GTA) was grafted to chitosan (CS) to obtain quaternary ammonium grafted chitosan (QCS) with enhanced antibacterial performance, and then cross-linked by dialdehyde terminated poly(ethylene oxide) (PEO DA) to construct QCS/PEO DA hydrogel with tissue adhesion, biodegradation and self-healing properties. The QCS/PEO DA hydrogel is loaded with tannin acid (TA) and deferoxamine (DFO) to enhance antioxidant property and angiogenesis. At the same time, the TA and DFO loaded TA@DFO/hydrogel preserved the biocompatibility and biodegradability of chitosan. Moreover, the multifunctional hydrogel behaved excellent hemostatic properties in mice model and significantly promoted the healing efficacy of diabetic wounds. Overall, the TA@DFO/hydrogel is promising anti-infection dressing material for diabetic wound healing.