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A novel tri-layered, functionally-graded chitosan membrane (FGM) with bioactive glass gradient (50%, 25%, and 0% wt.) was developed by lyophilization. A step-wise grading of chitosan, bioactive glass (BG), and Pluronic F127 was introduced into the membrane in which each layer has separate surface functions that play a role of guided tissue regeneration (GTR) membranes. The lower layer was designed to replicate alveolar bone and contains 50%wt. BG, the middle layer contains 25%wt. BG, while the upper layer was non-porous without BG and it did not support cell growth. Scanning Electron Microscopy (SEM) revealed that the lower FGM surface possessed a porous structure with embedded BG particles, while the upper surface was non-porous with interconnected architecture. The contact angle measurement confirmed that the surface with BG was hydrophilic (≈0 0 ), while the opposite surface was hydrophobic (91 0  ± 3.84 0 ). Both osteoblast and fibroblast cells have maximum adhesion at contact angle <80°. Alamar blue assay revealed the biocompatibility of the MC3T3-E1 mouse pre-osteoblasts cells with these membranes in vitro. The cells attachment and proliferation was seen for lower surface, while no cells adhesion was observed for the upper layer. Additionally, the interaction of the tissue with these tri-layered membranes was also investigated in vivo. Hematoxylin and eosin staining revealed the biocompatible nature of these membranes. Altogether, these results indicated that due to the biocompatible nature of these membranes, they will be a good carrier of in vivo implantation., (Copyright © 2019 Elsevier B.V. All rights reserved.)

With an increase in the demand for skin regeneration products, there is a noticeable increase in developing materials that encourage, wound healing and skin regeneration. It has been reported that antioxidants play an important role in anti-inflammatory reactions, cellular proliferation and remodeling phase of wound healing. While consideration all these factors, a novel α-tocopherol acetate (vitamin E) (VE) loaded bi-layered electrospun membrane, based on lower polycaprolactone (PCL) layer and upper polylactic acid (PLA) layer, was fabricated through electrospinning. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), in-vitro degradation studies, swelling studies and VE release studies were performed to evaluate structural, physical and in-vitro behavior of membranes. Biological properties of membranes were evaluated through cell proliferation assay, cell adhesion studies, live/dead cell assay and CAM assay. SEM images showed that the average diameter of nanofibers ranged from 1 to 6 μm, while addition of VE changed the diameter and morphology of fibers. Bi-layered membranes showed significant swelling behavior through water uptake, membranes loaded with 30% VE showed 8.7% and 6.8% degradation in lysozyme and H 2 O 2 respectively. 20% and 30% VE loaded membranes followed Korsmeyer-Peppas and first order drug release kinetics followed by non-fickian drug release kinetics. Membranes showed non-toxic behavior and supported cell proliferation via alamar blue assay, cell adhesion via SEM, cell viability via live/dead assay and wound healing by scratch assay. CAM assay showed that membranes having VE supported angiogenesis and showed significant formation of blood vessels making it suitable for skin regeneration and wound healing. Results showed that large surface area of nanofibers, porous structure and biocompatible nature are suitable for targeted clinical applications., (Copyright © 2019. Published by Elsevier B.V.)

In this study, an effective, biocompatible and biodegradable co-polymer comprising of chitosan (CS) and polyvinyl alcohol (PVA) hydrogels, chemically crosslinked and impregnated with doxazocin, is reported. The chemical structural properties of the hydrogels were evaluated by Fourier Transform Infrared spectroscopy (FTIR) and physical properties were analysed by scanning electron microscopy (SEM). The swelling behaviour is an important parameter for drug release mechanism and was investigated to find out the solution absorption capacity of the synthesized hydrogels. MTT assay revealed that doxazocin loaded hydrogels significantly hindered the cell viability. Flow cytometry analysis was performed to analyse the effect of 8CLH and 4CLH on regulation of cell cycle. Moreover, in vivo anti-cancer potential of synthesized hydrogels was assessed by CAM Assay. Results displayed that 8CLH with 1mg/ml of doxazocin had prominently decreased the angiogenesis and significantly increased the number of cells in G1 phase of cell cycle. These results declared that 8CLH will be a good addition among hydrogels used for treatment of cancer by onsite delivery of drug., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Our aim was to develop a biocompatible hydrogel that could be soaked in heparin and placed on wound beds to improve the vasculature of poorly vascularized wound beds. In the current study, a methodology was developed for the synthesis of a new chitosan derivative (CSD-1). Hydrogels were synthesized by blending CSD-1 for either 4 or 24h with polyvinyl alcohol (PVA). The physical/chemical interactions and the presence of specific functional groups were confirmed by Fourier transform infrared (FT-IR) spectroscopy and proton nuclear magnetic resonance ( 1 H NMR). The porous nature of the hydrogels was confirmed by scanning electron microscopy (SEM). Thermal gravimetric analysis (TGA) showed that these hydrogels have good thermal stability which was slightly increased as the blending time was increased. Hydrogels produced with 24h of blending supported cell attachment more and could be loaded with heparin to induce new blood vessel formation in a chick chorionic allantoic membrane assay., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Chitosan's poor solubility especially in organic solvents limits its use with other organo-soluble polymers; however such combinations are highly required to tailor their properties for specific biomedical applications. This paper describes the development of a new synthetic methodology for the synthesis of organo-soluble chitosan derivatives. These derivatives were synthesized from chitosan (CS), triethyl orthoformate and barbituric or thiobarbituric acid in the presence of 2-butannol. The chemical interactions and new functional motifs in the synthesized CS derivatives were evaluated by FTIR, DSC/TGA, UV/VIS, XRD and (1)H NMR spectroscopy. A cytotoxicity investigation for these materials was performed by cell culture method using VERO cell line and all the synthesized derivatives were found to be non-toxic. The solubility analysis showed that these derivatives were readily soluble in organic solvents including DMSO and DMF. Their potential to use with organo-soluble commercially available polymers was exploited by electrospinning; the synthesized derivatives in combination with polycaprolactone delivered nanofibrous membranes., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Periodontal disease is associated with the destruction of periodontal tissues, along with other disorders/problems including inflammation of tissues and severe pain. This paper reports the synthesis of meloxicam (MX) immobilized biodegradable chitosan (CS)/poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) based electrospun (e-spun) fibers and films. Electrospinning was employed to produce drug loaded fibrous mats, whereas films were generated by solvent casting method. In-vitro drug release from materials containing varying concentrations of MX revealed that the scaffolds containing higher amount of drug showed comparatively faster release. During initial first few hours fast release was noted from membranes and films; however after around 5h sustained release was achieved. The hydrogels showed good swelling property, which is highly desired for soft tissue engineered implants. To investigate the biocompatibility of our synthesized materials, VERO cells (epithelial cells) were selected and cell culture results showed that these all materials were non-cytotoxic and also these cells were very well proliferated on these synthesized scaffolds. These properties along with the anti-inflammatory potential of our fabricated materials suggest their effective utilization in periodontital treatments., (Copyright © 2016 Elsevier B.V. All rights reserved.)

This paper describes the development of a new crosslinking method for the synthesis of novel hydrogel films from chitosan and PVA for potential use in various biomedical applications. These hydrogel membranes were synthesized by blending different ratios of chitosan (CS) and poly(vinyl alcohol) (PVA) solutions and were crosslinked with 2.5% (w/v) triethyl orthoformate (TEOF) in the presence of 17% (w/v) sulfuric acid. The physical/chemical interactions and the presence of specific functional groups in the synthesized materials were evaluated by Fourier transform infrared (FT-IR) spectroscopy. The morphology, structure and pore size of the materials were investigated by scanning electron microscopy (SEM). Thermal gravimetric analysis (TGA) proved that these crosslinked hydrogel films have good thermal stability which was decreased as the CS ratio was increased. Differential scanning calorimetry (DSC) exhibited that CS and PVA were present in the amorphous form. The solution absorption properties were performed in phosphate buffer saline (PBS) solution of pH7.4. The 20% PVA-80% CS crosslinked hydrogel films showed a greater degree of solution absorption (183%) as compared to other compositions. The hydrogels with greater CS concentration (60% and 80%) demonstrated relatively more porous structure, better cell viability and proliferation and also revealed good blood clotting ability even after crosslinking. Based on the observed facts these hydrogels can be tailored for their potential utilization in wound healing and skin tissue engineering applications., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Development of biodegradable composites having the ability to suppress or eliminate the pathogenic micro-biota or modulate the inflammatory response has attracted great interest in order to limit/repair periodontal tissue destruction. The present report includes the development of non-steroidal anti-inflammatory drug encapsulated novel biodegradable chitosan (CS)/poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) electro-spun (e-spun) composite nanofibrous mats and films and study of the effect of heat treatment on fibers and films morphology. It also describes comparative in-vitro drug release profiles from heat treated and control (non-heat treated) nanofibrous mats and films containing varying concentrations of piroxicam (PX). Electrospinning was used to obtain drug loaded ultrafine fibrous mats. The physical/chemical interactions were evaluated by Fourier Transform Infrared (FT-IR) spectroscopy. The morphology, structure and pore size of the materials were investigated by scanning electron microscopy (SEM). The thermal behavior of the materials was investigated by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). Control (not heat treated) and heat treated e-spun fibers mats and films were tested for in vitro drug release studies at physiological pH7.4 and initially, as per requirement burst release patterns were observed from both fibers and films and later sustained release profiles were noted. In vitro cytocompatibility was performed using VERO cell line of epithelial cells and all the synthesized materials were found to be non-cytotoxic. The current observations suggested that these materials are potential candidates for periodontal regeneration., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The aim was to develop an obturating material which has the tendency to release fluoride and minimize interfaces with tooth. Nano-fluorapatite (nFA) powder was synthesized by sol-gel. The composite based on polyurethane (PU) was obtained by chemically binding the nFA (10, 15, 20%wt/wt) to the diisocyanate component by utilizing in-situ polymerization. The procedure involved stepwise addition of monomeric units of PU, and optimizing the reagent concentrations to synthesize composite. The structural, phase and morphological analysis of nFA was evaluated. The structural, fluoride release and in-vitro adhesion analysis with tooth structure of PU/nFA was conducted. For fluoride release analysis the samples were stored in artificial saliva and deionized water for periodical time intervals. Bond strength of composites was analyzed by push-out test. Chemical linkage was achieved between PU and nFA without intermediate coupling agent. The insignificant difference of fluoride release pattern was observed in artificial saliva and (p≥0.05) deionized water. The PU/nFA composite provided sustained release of fluoride over a long period of time. The composite showed more adhesion toward tooth structure with the increase in concentration of nFA. Bond strength of composite was in accordance with root canal filling material, hence, the material with anti-cariogenic properties can be used as an obturating material., (Copyright © 2013 Elsevier B.V. All rights reserved.)