Transvaginal repair of anterior vaginal wall prolapse with polyvinylidene fluoride (PVDF) mesh: an alternative for previously restricted materials?

INTRODUCTION AND HYPOTHESIS: To study the mid-term safety and functional outcomes of transvaginal anterior vaginal wall prolapse repair using polyvinylidene fluoride (PVDF) mesh (DynaMesh®-PR4) by the double trans-obturator technique (TOT). METHODS: Between 2015 and 2020, we prospectively included women with symptomatic high-stage anterior vaginal wall prolapse with or without uterine prolapse or stress urinary incontinence (SUI) in the study. The patients underwent transvaginal repair of the prolapse using PVDF mesh in two medical centers. We followed all patients for at least 12 months. We recorded the characteristics of vaginal and sexual symptoms, urinary incontinence, and prolapse stage pre- and postoperatively using International Consultation on Incontinence Questionnaire-Vaginal Symptoms (ICIQ-VS), International Consultation on Incontinence Questionnaire-Urinary Incontinence-Short Form (ICIQ-UI-SF), and Pelvic Organ Prolapse Quantification (POP-Q) system, respectively. RESULTS: One hundred eight women were included in the final analysis with a mean follow-up time of 34.5 ± 18.6 months. The anatomical success was achieved in 103 (95.4%) patients. There was a significant improvement in patients' vaginal symptoms, urinary incontinence, and quality of life scores postoperatively (p < 0.0001). Only six patients (5.5%) had mesh extrusion, five of whom were managed successfully. The total rates of complications and de novo urinary symptoms were 21.3% and 7.4%, respectively. Significant pain was reported in 17 cases (15.7%). CONCLUSION: Our findings show that using PVDF mesh in the double TOT technique for anterior vaginal wall prolapse repair is a safe procedure with high anatomic and functional success rates and acceptable complication rates in mid-term follow-up.

Development of Polyvinyl Alcohol/Kaolin Sponges Stimulated by Marjoram as Hemostatic, Antibacterial, and Antioxidant Dressings for Wound Healing Promotion.

The predominant impediments to cutaneous wound regeneration are hemorrhage and bacterial infections that lead to extensive inflammation with lethal impact. We thus developed a series of composite sponges based on polyvinyl alcohol (PVA) inspired by marjoram essential oil and kaolin (PVA/marjoram/kaolin), adopting a freeze-thaw method to treat irregular wounds by thwarting lethal bleeding and microbial infections. Microstructure analyses manifested three-dimensional interconnected porous structures for PVA/marjoram/kaolin. Additionally, upon increasing marjoram and kaolin concentrations, the pore diameters of the sponges significantly increased, recording a maximum of 34 ± 5.8 µm for PVA-M0.5-K0.1. Moreover, the porosity and degradation properties of PVA/marjoram/kaolin sponges were markedly enhanced compared with the PVA sponge with high swelling capacity. Furthermore, the PVA/marjoram/kaolin sponges exerted exceptional antibacterial performance against Escherichia coli and Bacillus cereus, along with remarkable antioxidant properties. Moreover, PVA/marjoram/kaolin sponges demonstrated significant thrombogenicity, developing high thrombus mass and hemocompatibility, in addition to their remarkable safety toward fibroblast cells. Notably, this is the first study to our knowledge investigating the effectiveness of marjoram in a polymeric carrier for prospective functioning as a wound dressing. Collectively, the findings suggest the prospective usage of the PVA-M0.5-K0.1 sponge in wound healing for hemorrhage and bacterial infection control.

TiO2@HNTs Robustly Decorated PVDF Membrane Prepared by a Bioinspired Accurate-Deposition Strategy for Complex Corrosive Wastewater Treatment.

As industrialization has spread all around the world, the problems of water pollution such as offshore oil spill and industrial sewage discharge have spread with it. Although many new separation materials have been successfully developed to deal with this crisis, a large number of water treatment materials only focus on the treatment of classified single water pollutant under mild conditions. It is a great challenge to treat soluble contaminants such as water-soluble dyes and insoluble contaminants, for example, emulsified oils simultaneously in a strong corrosive environment. Herein, in this work, corrosive resistance and multifunctional surface on a commercial polyvinylidene difluoride (PVDF) membrane via a tunicate-inspired gallic acid-assisted accurate-deposition strategy is created. Owing to the titanium-carboxylic coordination bonding and accurate-deposition strategy, the as-prepared membrane exhibits extraordinary stability, facing various harsh environmental challenges and incredibly corrosive situations (e.g., 4 M NaOH, 4 M HCl, and saturated NaCl solution). The robust multifunctional surface also endows commercial PVDF membrane with the ability for in situ separation and adsorption of surfactant-stabilized oil-in-water (corrosive and dyed) emulsions with high adsorption efficiencies up to 99.9%, separation efficiencies above 99.6%, and permeation flux as high as 15,698 ± 211 L/(m2·h·bar). Furthermore, the resultant membrane can be regenerated facilely and rapidly by flushing a small amount of HCl (4 M) or NaOH (4 M), making the corrosive resistance membrane attain a long-term and high-efficiency application for complex dyed wastewater treatment. Therefore, the multifunctional membrane has a broad application prospect in the industrial field.

Litsea cubeba fruit essential oil and its major constituent citral as volatile agents in an antimicrobial packaging material.

Food packaging films were coated with polyvinyl acetate (PVA) containing different concentrations of citral or Litsea (L.) cubeba essential oil (EO). Antimicrobial contact trials in style of ISO22916 were performed. Citral coatings achieved bactericidal effects against Escherichia coli (2.1 log) and Staphylococcus aureus (4.3 log) at concentrations of 20%DM. L. cubeba inactivated more than 4 log cycles of both bacteria at a concentration of 20%DM. To determine the antimicrobial activity across the gas phase, a unique method for volatile agents was developed, adapting ISO22196. GC/MS measurements were performed to supplement microbiological tests in a model packaging system with a defined 220 ml headspace (HS). HS-equilibrium concentrations of 1.8 µg/mlAir were found for 20%DM 'citral-coatings, resulting in antimicrobial effects of 3.8 log against of E. coli. Saccharomyces cerevisiae (4.74 log) and Aspergillus niger (4.29 log) were more effectively inactivated by 3%DM and 5%DM coatings. In an application trial with strawberries, simulating a headspace packaging, growth inhibitory effects on the yeast and mold microbiota were found for the 20%DM coatings.

Design and synthesis of transparent and flexible nanofibrillated cellulose films to replace petroleum-based polymers.

Nanofibrillated cellulose films have garnered attention due to their interesting proprieties such as transparency and high mechanical strength. However, they are brittle, very hydrophilic, which is decreasing their potential applications. We have successfully achieved a simple and effective chemical modification based on polymer grafting and through plasticizer additions to increase the performance of the films as well as to improve the compatibility within conventional polymer. A preliminary study shows the possibility of using this film as an interlayer in safety glazing and/or bulletproof glass with polyvinyl butyral (PVB). The modified NFC films displays high optical transmittance (93 %), increases tensile stretch and is more hydrophobic (83°). A higher flexibility was also achieved, as the film was greatly stretched and bended without cracking or breaking. The NFC / PVB composite has three times more elongation at break, 13 % more specific energy absorbed with a half-tensile stress compared to an interlayer of PVB.

Chitosan-polyvinylpyrrolidone CoxFe3-xO4 (0.25 ≤ x ≤ 1) nanoparticles for hyperthermia applications.

Blends of chitosan (CS) and polyvinylpyrrolidone (PVP) with cobalt ferrite nanoparticles (CoFe2O4) have the potential for use in several biomedical applications as drug delivery systems and for hyperthermia applications. Herein, we present a detailed study of the effect of chitosan and PVP on the structural, magnetic and specific absorption rate (SAR) properties of CoxFe3-xO4 (x = 0.25, 0.50, 0.75 and 1.00) as an effective heat nanomediator for hyperthermia. Structural characterization was carried out using X-ray diffraction (XRD), infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Magnetic properties as a function of the Co2+ content were studied using a vibrating sample magnetometer (VSM) at room temperature. Hyperthermia investigations were performed at 454 ±â€¯20 kHz with a magnetic field amplitude of 5.5 mT. CS-PVP coated nanoparticles at x = 1.00 show a maximum SAR of 386 W/g, while bare nanoparticles show a SAR of 270 W/g. The advantage of the designed nanoparticles coated system lies in the fact that the versatile blending of chitosan and PVP enhance the SAR properties for hyperthermia of cobalt ferrite nanoparticles and provide biocompatibility and stability to the samples.

Optimization and validation of automated solid-phase microextraction arrow technique for determination of phosphorus flame retardants in water.

In the present work, a very sensitive and fully automated direct immersion PAL SPME Arrow procedure, coupled with GC-MS, has been developed and validated for determination of nine phosphorus flame retardants in different types of water samples (river, drinking and rainwater). PDMS/DVB was selected among three commercially available SPME Arrows (PDMS/DVB, DVB/PDMS/CWR and PDMS/CWR), since it resulted in the best sensitivity. The important experimental parameters were optimized via a central composite design response surface methodology and as result, extraction time of 65 min, extraction temperature of 80 °C and added salt concentration of 19% (w/v), were selected as the optimum values. The optimized method showed linear response over the calibration range (2 - 500 ng L-1), with R2-values higher than 0.9937. The precision (RSD%) measured by replicate analyses (n = 7) was estimated at 2 and 100 ng L-1 and was less than 29% and 21%, respectively. The LOQ of PAL SPME Arrow, calculated as S/N = 10, was between 0.2 and 1.2 ng L-1 (for triphenyl phosphate and tris-(1­chloro­2-propyl) phosphate, respectively) with extraction efficiencies between 5.9 and 31% (for tris-(1,3-dichloro-2-propyl) phosphate and tri-n­butyl phosphate, respectively). To assess the performance of the developed technique for real samples, two river water samples, tap water from two regions and a rainwater sample were analyzed. Most of the target analytes were observed in the river samples with concentrations of 1.0 - 250 ng L-1 and the obtained recoveries at 50 ng L-1 ranged between 60 and 107%. Considering the figures of merit of the optimized method, PAL SPME Arrow-GC-MS showed to be the most sensitive analytical approach for determination of phosphorus flame retardants in water, with satisfying precision and accuracy, compared with conventional SPME-NPD, LLE-GC-MS and SPE-LC-MS/MS.

Grape seed extract-soluplus dispersion and its antioxidant activity.

OBJECTIVE: The main objective of this work was to formulate a nanodispersion containing grape seed extract and analyzed its release profile, antioxidant potential of the prepared formulations. METHODS: The grape seed extract (GSE) containing proanthocyanidins (PC's) has been dispersed in polymer matrix soluplus (SOLU) by the freeze-drying method. The morphological analysis was carried out using atomic force microscopy (AFM), scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). The in-vitro release of the nanodispersion formulations was evaluated by simulated intestinal fluid (SIF). The antioxidant activity of GSE and the formulation were evaluated by employing various in-vitro assays such as 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), 2, 2-diphenyl-1- picrylhydrazyl (DPPH), Ferric reducing antioxidant power (FRAP) and peroxidation inhibiting activity. RESULTS: The formulation FIII (1:5) resulted in a stable formulation with a higher loading efficiency of 95.36%, a particle size of 69.90 nm, a polydispersity index of 0.154 and a zeta potential value of -82.10 mV. The antioxidant efficiency of GSE-SOLU evaluated by DPPH was found to be 96.7%. The ABTS and FRAP model exhibited a dose-dependent scavenging activity. Linoleic model of FIII formulation and GSE exhibited a 66.14 and 86.58% inhibition respectively at 200 µg/l. CONCLUSIONS: The main reason for excellent scavenging activity of the formulations can be attributed to the presence of monomeric, dimeric, oligomeric procyanidins and the phenolic group. The present work denotes that GSE constitutes a good source of PC's and will be useful in the prevention and treatment of free radical related diseases.

Finely tuned Prussian blue-based nanoparticles and their application in disease treatment.

The Prussian blue (PB) based nanostructure is a mixed-valence coordination network with excellent biosafety, remarkable photothermal effect and multiple enzyme-mimicking behaviours. Compared with other nanomaterials, PB-based nanoparticles (NPs) exhibit several unparalleled advantages in biomedical applications. This review begins with the chemical composition and physicochemical properties of PB-based NPs. The tuning strategies of PB-based NPs and their biomedical properties are systemically demonstrated. Afterwards, the biomedical applications of PB-based NPs are comprehensively recounted, mainly focusing on treatment of tumors, bacterial infection and inflammatory diseases. Finally, the challenges and future prospects of PB-based NPs and their application in disease treatment are discussed.

Preparation and antitumor evaluation of hinokiflavone hybrid micelles with mitochondria targeted for lung adenocarcinoma treatment.

Hinokiflavone (HF) is a natural biflavonoid extracted from medicinal plants such as Selaginella tamariscina and Platycladus orientalis. HF plays a crucial role in the treatment of several cancers. However, its poor solubility, instability, and low bioavailability have limited its use. In this study, soluplus/d-α-tocopherol acid polyethylene glycol 1000 succinate (TPGS)/dequalinium (DQA) was applied to improve the solubilization efficiency and stability of HF. HF hybrid micelles were prepared via thin-film hydration method. The physicochemical properties of micelles, including particle size, zeta potential, encapsulation efficiency, drug loading, CMC value, and stability were investigated. The in vitro cytotoxicity assay showed that the cytotoxicity of the HF hybrid micelles was higher than that of free HF. In addition, the HF hybrid micelles improved anticancer efficacy and induced mitochondria-mediated apoptosis, which is associated with the high levels of ROS inducing decreased mitochondrial membrane potential, promoting apoptosis of tumor cells. Furthermore, in vivo tumor suppression, smaller tumor volume and increased expression of pro-apoptotic proteins were found in nude mice treated with HF hybrid micelles, suggesting that HF hybrid micelles had stronger tumor suppressive activity compared with free HF. In summary, HF hybrid micelles developed in this study enhanced antitumor effect, which may be a potential drug delivery system for the treatment of lung adenocarcinoma.

Fabrication and characterization of herbal drug enriched Guar galactomannan based nanofibrous mats seeded with GMSC's for wound healing applications.

Electrospun nanofibrous Guar gum/PVA based scaffold matrix incorporated with standardized extracts of four traditional medicinal plants of wound healing repute namely - Acalypha indica (A.i), Aristolochia bracteolata (A.b), Lawsonia inermis (L.i) and Thespesia populnea (T.p) was developed. Combinatorial ratio optimization of the extracts subject to their impact on nanofibre morphology, thermal and swelling stability resulted in a 4:4:1:1 blend of A.i, A.b, T.p and L.i at 20% of the total weight of the polymer mix. Dermal toxicity studies on female wistar rats established the nontoxicity of the generated Scaffold/Dressing. Cutaneous wound healing ability of Mesenchymal Stem Cells (MSC's) is well characterized to amplify their delivery and efficacy at the wound site. Apart from ease of accessibility, increased immune modulation of Gingival MSC's is their clear merit relative to those conventionally sourced from adipose tissues and bone marrow. A population of cells were isolated from discarded sample of human gingiva, following standard procedures and characterized as per minimal criteria as described by International Society for Cellular Therapy's (ISCT). The Cytocompatibility and proliferation of GMSC's were evaluated by MTT and Calcein AM assay demonstrating the viability of the seeded GMSC's up to 6 days. In vivo efficacy of the scaffold with and without GMSC's showed complete restoration of the tissue with minimal scarring. This investigation thus generated an herb drug enriched nanofibrous mat as a dressing and also a skin like scaffold with GMSC's, integrating the biological and technological benefits of herbal medicine and stem cell therapy respectively for skin regenerative applications.

Understanding the interaction between Soluplus® and biorelevant media components.

Soluplus® (polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer) is a solubilizing copolymer commonly applied as carrier in solid dispersions of poorly soluble drugs. This polymer is used to increase the apparent solubility of drugs with low aqueous solubility and consequently enhance drug absorption by the human gastrointestinal tract. To select the appropriate carrier to compose solid dispersions, in vitro supersaturation studies were applied as a pre-formulation tool, using different dissolution media. During in vitro supersaturation studies performed for the poorly soluble drug candesartan cilexetil, it was found that Soluplus® may interact with components of the biorelevant medium Fasted State Simulated Intestinal Fluid, lowering the drug apparent solubility. Dynamic Light Scattering and Transmission Electron Microscopy analyses were performed, as well as fluorescence measurements, aiming to characterize the interaction behavior and determine the polarity of the microenvironment. It was evidenced that Soluplus® interacted preferentially with lecithin, forming mixed micelles with a more polar microenvironment, which lowered the candesartan cilexetil solubilization capacity and consequently reduced its apparent solubility in the biorelevant medium. These findings are important to emphasize the key role of the media selection for in vitro solubility-supersaturation studies, where media that could mimic the human gastrointestinal environment are recommended.

Five-Stage Approach for a Systematic Screening and Development of Etravirine Amorphous Solid Dispersions by Hot-Melt Extrusion.

The aim of this study was to develop a fast, effective, and material sparing screening method to design amorphous solid dispersions (ASDs) of etravirine to drive more effectively the development process, leading to improved bioavailability (BA) and stability. A systematic step-by-step approach was followed by combining theoretical calculations with high-throughput screening (HTS) and software-assisted multivariate statistical analysis. The thermodynamic miscibility and interaction of the drug in several polymers were predicted using Hansen solubility parameters (δ). The selected polymers were evaluated by HTS, using solvent evaporation. Binary compositions were evaluated by their solubilization capacity and physical stability over 2 months. JMP 14.0 was used for multivariate statistical analysis using principal components analysis. Extrusion was performed in Thermo Scientific HAAKE MiniLab II, and extrudates were characterized by assay, related substances, dissolution, and physical state (polarized light microscopy (PLM), Raman spectroscopy, and X-ray powder diffraction (XRPD)). A short stability study was performed where milled extrudates were exposed to 25 °C/60%RH and 40 °C/75%RH for 3 months. Through thermodynamic predictions, five main polymers were selected. The HTS enabled the evaluation of 42 formulations for solubilization capacity and physical stability. The three most promising compositions were selected for hot-melt extrusion (HME) tests. In general, a good correlation was found among the results of theoretical predictions, HTS, and HME. Poly(vinylpyrrolidone) (PVP)-based formulations were shown to be easily extrudable, with low degradation and complete amorphicity, whereas in Soluplus, the drug was not miscible, leading to a high crystalline content. The drug release rate was improved more than two times with PVP, and the manufactured ASD was demonstrated to be stable physically and chemically. A fast and effective screening technique to develop stable ASDs for a poorly soluble drug was successfully developed as applied to etravirine. The given method is easy to use, requires a low amount of drug, and is fairly accurate in predicting the amorphization of the drug when formulated. The success of HME formulation development of etravirine was undoubtedly enhanced with this high-throughput tool, which led to the identification of extrudates with improved biopharmaceutical properties. The structural characterization performed by PLM, XRPD, and Raman spectroscopy demonstrated that the HME prototype was essentially amorphous. The unexpected stability at 40 °C/75%RH was correlated with the presence of molecular interaction characterized by Raman spectroscopy.

Nano formulated proanthocyanidins as an effective wound healing component.

Proanthocyanidins (PCs), a component of grape seed extract (GSE), have recently being used for the treatment of wounds. However, poor absorption, poor stability and rapid elimination from the systemic circulation limit its acceptance. In addressing these problems, we herein report the development of PCs based nanoformulations (PCs/SOLU) for the first time based on 1% GSE and assessed its wound healing potential in-vivo on the wistar rats. GSE and PCs/SOLU nanodispersions 1% were prepared by incorporating them into the ointment base via uniform mixing to form ointment which could be easily applied topically to wounds. The antibacterial activity of PCs/SOLU against gram positive and gram-negative bacteria strains proved that the cell membranes became more permeable with disrupted cell structure. While carrageenan and histamine induced rat paw edema analyses show there was no inflammatory signs in animals treated with 1 wt% of PCs/SOLU nanodispersion. Excision wound measuring about 3 cm in depth was created on the wistar rats. The ointment was applied topically on the wounded site and the wound contraction was measured daily. Grape seed extract (GSE) ointment, ointment base and povidone­iodine (Povi-Iod) ointment of about 1% was used as the control, positive and negative standards. PCs/SOLU nanodispersion heals the wound by mobilising the fibroblasts in the wound site and inhibits the inflammatory response through decreased expression of monocyte. The macroscopical, immunological and histopathological assessments revealed that PCs/SOLU nanodispersion ointment usage improves the cell adhesion and proliferation.

A multifunctional long-term release system for treatment of hypothyroidism.

Hypothyroidism is an autoimmune disease associated with underactive thyroid gland. In this study, a dual effect polymeric system was designed to release Cepharanthine (CEP) to block T cell activation and Selenium (Se) to decrease the anti-thyroid peroxidase (TPOAb) concentration in order to treat hypothyroidism. For this purpose, poly(ethylene-vinyl acetate) (PEVA) and polyethylene glycol (PEG) nanoparticles (NPs) including CEP were synthesized by emulsion solvent evaporation method and they were loaded to polyurethane (PU)/PEG-PUSe-PEG block copolymer blends which were fabricated by particulate leaching technique as porous sponges. Fourier-Transform Infrared (FTIR), Raman, and Nuclear Magnetic Resonance (NMR) analysis showed successful synthesis of PEG-PUSe-PEG block copolymer. A long-term zero-order release profile was obtained for CEP. Se release rate from matrices showed an oxidative stress-mediated release which can be used to adjust Se amount. According to MTS results conducted by NIH 3T3 fibroblasts, both NPs and matrices have no adverse effect on cell viability. Fluorescence microscopy and SEM images confirm the MTS results. The dual release system has potential to be effectively used in long-term treatment of hypothyroidism by addressing both auto-immune response and hormone regulation.

Characterization of non-covalent immobilized Candida antartica lipase b over PS-b-P4VP as a model bio-reactive porous interface.

The design of interfaces that selectively react with molecules to transform them into compounds of industrial interest is an emerging area of research. An example of such reactions is the hydrolytic conversion of ester-based molecules to lipids and alcohols, which is of interest to the food, and pharmaceutical industries. In this study, a functional bio-interfaced layer was designed to hydrolyze 4-nitrophenyl acetate (pNPA) and Ricinus Communis (castor) oil rich in triglycerides using lipase b from Candida antarctica (CALB, EC 3.1.1.3). The attachment of CALB was performed via non-covalent immobilization over a polymer film of vertically aligned cylinders that resulted from the self-assembly of the di-block copolymer polystyrene-block-poly(4-vinyl pyridine) (PS-b-P4VP). This polymer-lipase model will serve as the groundwork for the design of further bioactive layers for separation applications requiring similar hydrolytic processes. Results from the fabricated functional bio-interfaced material include cylinders with featured pore size of 19 nm, d spacing of 34 nm, and ca. 40 nm of thickness. The polymer-enzyme layers were physically characterized using AFM, XPS, and FTIR. The immobilized enzyme was able to retain 91% of the initial enzymatic activity when using 4-nitrophenyl acetate (pNPA) and 78% when exposed to triglycerides from castor oil.

Development and characterization of octreotide-modified curcumin plus docetaxel micelles for potential treatment of non-small-cell lung cancer.

We prepared octreotide (OCT)-modified curcumin plus docetaxel micelles to enhance active targeting and inhibit tumor metastasis by destroying vasculogenic mimicry (VM) channels. Soluplus was applied as an amphiphilic material to form micelles via film dispersion. The cytotoxic effects, active cellular targeting, and inhibitory effects on metastasis were systematically evaluated in vitro using A549 cells, and in vivo antitumor effects were evaluated using xenograft tumor-bearing mice. In vitro assays indicated that the OCT-modified curcumin plus docetaxel micelles showed robust cytotoxicity on A549 cells and effectively inhibited VM channels and tumor metastasis. Studying the mechanism of action indicated that OCT-modified curcumin plus docetaxel micelles downregulated MMP-2 and HIF-1α. In vivo assays indicated that OCT-modified curcumin plus docetaxel micelles increased drug accumulation at tumor sites and showed obvious antitumor efficacy. The developed OCT-modified curcumin plus docetaxel micelles may offer a promising treatment strategy for non-small-cell lung cancer.

Construction of 2D Antimony(III) Selenide Nanosheets for Highly Efficient Photonic Cancer Theranostics.

Photonic cancer hyperthermia has been considered to be one of the most representative noninvasive cancer treatments with high therapeutic efficiency and biosafety. However, it still remains a crucial challenge to develop efficient photothermal nanoagents with satisfactory photothermal performance and biocompatibility, among which two-dimensional (2D) ultrathin nanosheets have recently been regarded as the promising multifunctional theranostic agents for photothermal tumor ablation. In this work, we report, for the first time, on the construction of a novel kind of photothermal agents based on the intriguing 2D antimony(III) selenide (Sb2Se3) nanosheets for highly efficient photoacoustic imaging-guided photonic cancer hyperthermia by near-infrared (NIR) laser activation. These Sb2Se3 nanosheets were easily fabricated by a novel but efficiently combined liquid nitrogen pretreatment and freezing-thawing approach, which were featured with high photothermal-conversion capability (extinction coefficient: 33.2 L g-1 cm-1; photothermal-conversion efficiency: 30.78%). The further surface engineering of these Sb2Se3 ultrathin nanosheets with poly(vinyl pyrrolidone) (PVP) substantially improved the biocompatibility of the nanosheets and their stability in physiological environments, guaranteeing the feasibility in photonic antitumor applications. Importantly, 2D Sb2Se3-PVP nanosheets have been certificated to efficiently eradicate the tumors by NIR-triggered photonic tumor hyperthermia. Especially, the biosafety in vitro and in vivo of these Sb2Se3 ultrathin nanosheets has been evaluated and demonstrated. This work meaningfully expands the biomedical applications of 2D bionanoplatforms with a planar topology through probing into new members (Sb2Se3 in this work) of 2D biomaterials with unique intrinsic physiochemical property and biological effect.

Silver triethanolamine-loaded PVB/CO films for a potential liquid bandage application.

Many studies have reported that silver has excellent antibacterial properties. However, silver ions can easily react with oxygen to form Ag2O, thus leading to a color change and a reduction in its anti-microbial characteristics. In this study, silver triethanolamine- (ST) loaded PVB/CO solution was prepared as a potential candidate liquid bandage. PVB/CO/ST retained high transparency after exposure to light for 12 months, which allowed convenient inspection of the wound bed without removal of the dressing. The PVB/CO/ST film exhibited favorable properties, such as speed of drying, excellent tensile strength and elongation characteristics and water vapor transmission rate (WVTR). It was comfortable and waterproof, and therefore effective at preventing bacterial invasion, providing effective biosafety. PVB/CO/ST solution-treated wounds exhibited accelerated healing and reduced inflammation in a nude mouse mode. Our data suggested that PVB/CO/ST solution could serve as a promising liquid bandage for treatment of minor trauma.

Nano CuAl2O4 spinel mineral as a novel antibacterial agent for PVDF membrane modification with minimized copper leachability.

The employment of copper-containing antibacterial agents for membrane modification can constrain undesirable bacterial adhesion and growth in an effective and economical way. However, copper ion may be leached out and cause further toxicity after applying those materials for membrane processes. Therefore, in this study, nano CuAl2O4 spinel was synthesized as a novel copper-containing material which was expected to have good antibacterial activity and simultaneously stabilize copper ions by its intrinsic structure. The obtained nano spinel was applied for membrane modification via both doping and coating methods. Results show that the addition of nano CuAl2O4 spinel during doping process can change polyvinylidene fluoride (PVDF) membrane properties (crystallization, tensile strength, porosity, pore size distribution, permeate flux and bovine serum albumin (BSA) rejection) obviously, but no obvious change was observed for the coated membrane except increased hydrophilicity and permeate flux. Most importantly, the amount of bacteria attachment was found to reduce significantly (˜68%) on the membrane coated with nano spinel, which indicates the successful application of nano CuAl2O4 spinel as a novel antibacterial agent for membrane modification without extra concern of copper toxicity.