Browsing by Author "Shelma, R"
Now showing 1 - 5 of 5
Results Per Page
Sort Options
Item Characterization of surface modified polyester fabric(JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE, 2009) Joseph, R; Shelma, R; Rajeev, A; Muraleedharan, CVWoven polyethylene terephthalate (PET) fabric has been used in the construction of vascular grafts and sewing ring of prosthetic heart valves. In an effort to improve haemocompatibility and tissue response to PET fabric, a fluoropolymer, polyvinylidine fluoride (PVDF), was coated on PET fabric by dip coating technique. The coating was found to be uniform and no significant changes occurred on physical properties such as water permeability and burst strength. Cell culture cytotoxicity studies showed that coated PET was non-cytotoxic to L929 fibroblast cell lines. In vitro studies revealed that coating improved haemocompatibility of PET fabric material. Coating reduced platelet consumption of PET fabric by 50%. Upon surface modification leukocyte consumption of PET was reduced by 24%. About 60% reduction in partial thromboplastin time (PTT) observed when PET was coated with PVDF. Results of endothelial cell proliferation studies showed that surface coating did not have any substantial impact on cell proliferation. Overall results indicate that coating has potential to improve haemocompatibility of PET fabric without affecting its mechanical performance.Item Characterization of surface modified polyester fabric.(Journal of materials science. Materials in medicine, 2009)Woven polyethylene terephthalate (PET) fabric has been used in the construction of vascular grafts and sewing ring of prosthetic heart valves. In an effort to improve haemocompatibility and tissue response to PET fabric, a fluoropolymer, polyvinylidine fluoride (PVDF), was coated on PET fabric by dip coating technique. The coating was found to be uniform and no significant changes occurred on physical properties such as water permeability and burst strength. Cell culture cytotoxicity studies showed that coated PET was non-cytotoxic to L929 fibroblast cell lines. In vitro studies revealed that coating improved haemocompatibility of PET fabric material. Coating reduced platelet consumption of PET fabric by 50%. Upon surface modification leukocyte consumption of PET was reduced by 24%. About 60% reduction in partial thromboplastin time (PTT) observed when PET was coated with PVDF. Results of endothelial cell proliferation studies showed that surface coating did not have any substantial impact on cell proliferation. Overall results indicate that coating has potential to improve haemocompatibility of PET fabric without affecting its mechanical performance.Item Development and characterization of self-aggregated nanoparticles from anacardoylated chitosan as a carrier for insulin(CARBOHYDRATE POLYMERS, 2010) Shelma, R; Paul, W; Sharma, CPNanoparticulate carriers made from biodegradable polymers especially from chitosan seems to be an excellent approach to increase the uptake and transport of orally administered insulin. Various approaches have been studied to develop nanoparticles from chitosan including self-aggregated nanoparticles from hydrophobically modified chitosan. Anacardic acid is a naturally occurring fatty acid having bulky aromatic group as well as long aliphatic chain and an amphiphilic monomer of great potential. An attempt has been made to develop and characterize self-aggregated nanoparticles from chitosan modified with anacardic acid. Anacardoylated chitosan spontaneously formed nanoparticles in aqueous insulin solution with a particles size of 214 nm diameter at neutral pH. The hydrophobic nature of the nanoparticles helped in the Sustained release of insulin in the intestinal environment and the released insulin was stable and retained its conformation. However, it released insulin in acidic conditions and need to be encapsulated in alginate to render pH sensitiveness. (C) 2009 Elsevier Ltd. All rights reserved.Item In vitro and in vivo evaluation of curcumin loaded lauroyl sulphated chitosan for enhancing oral bioavailability(Carbohydr Polym., 2013-04) Shelma, R; Sharma, CPItem In Vitro Cell Culture Evaluation and In Vivo Efficacy of Amphiphilic Chitosan for Oral Insulin Delivery(JOURNAL OF BIOMEDICAL NANOTECHNOLOGY, 2013) Shelma, R; Sharma, CPThe overall goal of this paper was to enhance the bioavailability of orally delivered insulin. A mucoadhesive amphiphilic chitosan derivative, lauroyl sulphated chitosan (LSCS) was used as the oral carrier for insulin. Trans epithelial electrical resistance experiment was performed on Caco-2 cell monolayers and observed a reduction of TEER after the incubation with the particles. The insulin transport experiment was done with excised rat intestinal tissue using an Ussing chamber and observed an enhanced transport of insulin due to the effect of LSCS. Following oral administration of FITC-insulin loaded LSCS in SD rats; the qualitative biodistribution of the administered drug was investigated using a fluorescence microscopy. The results showed the time dependent distribution of insulin through gastro intestinal tract (GIT). The efficacy of insulin-loaded LSCS sub micro particles (LSCS-ins) was investigated in diabetic rats by measuring the blood glucose level and found to be an effective reduction of the blood glucose level after oral administration of LSCS-ins. The pharmacological availability was found to be 2.5-fold and had a longer pharmacological activity compared with that of native insulin via oral and subcutaneous (sc) routes. The enhanced oral bioavailability of insulin may be associated with a higher release rate in the intestinal juice, enhanced absorption by improved permeability and increased residence time in the intestinal cavity. Thus, encapsulating insulin in LSCS matrix is a promising carrier for sustained and controlled drug delivery with improved bioavailability of insulin for diabetic patients.