Severe blood loss due to traumatic injuries remains one of the leading causes of death in emergency settings.Chitosan continues to be the candidate material for hemostatic applications due to its inherent hemostatic p...Severe blood loss due to traumatic injuries remains one of the leading causes of death in emergency settings.Chitosan continues to be the candidate material for hemostatic applications due to its inherent hemostatic properties.However,available chitosan-based dressings have been reported to have an acidic odor at the wound site due to the incorporation of acid based solvents for their fabrication and deformation under compression owing to low mechanical strength limiting its usability.In the present study semi-IPN cryogel was fabricated via Schiff's base cross-linking between the polyaldehyde groups of oxidized dextran and thiolated chitosan in presence of locust bean gum(LBG)known for its hydrophilicity.Polymerization at12C yielded macroporous semi-IPN cryogels with an average pore size of 124.57±20.31 mm and 85.46%porosity.The hydrophobicity index of LBG reinforced semi-IPN cryogel was reduced 2.42 times whereas the swelling ratio was increased by 156.08%compare to control cryogel.The increased hydrophilicity and swelling ratio inflated the compressive modulus from 28.1 kPa to 33.85 for LBG reinforced semi-IPN cryogel.The structural stability and constant degradation medium pH were also recorded over a period of 12 weeks.The cryogels demonstrated lower adsorption affinity towards BSA.The cytotoxicity assays(direct,indirect)with 3T3-L1 fibroblast cells confirmed the cytocompatibility of the cryogels.The hemolysis assay showed<5%hemolysis confirming blood compatibility of the fabricated cryogel,while whole blood clotting and platelet adhesion assays confirmed the hemostatic potential of semi-IPN cryogel.展开更多
Biomimetic cell culture substrates are developed as an alternative to the conventional substrates.They provide necessary biochemical and biophysical cues to the cells from their surrounding environment for their optim...Biomimetic cell culture substrates are developed as an alternative to the conventional substrates.They provide necessary biochemical and biophysical cues to the cells from their surrounding environment for their optimal growth,behaviour and physiology.Changes in physiology of cells growing on biomimetic substrate can essentially affect results of in vitro biological experiments such as drug cytotoxicity,nanoparticle internalization or signalling pathways.As majority of ECM proteins are fibrous in nature,nanofibrous scaffolds have more biomimicking properties.Therefore,in this study,we developed ECM mimicking polycaprolactone-chitosan nanofiber substrate and evaluated its effect on cell morphology,proliferation,cell cycle and ECM production.Further,cellular uptake of BSA-AuNCs has been assessed on conventional and biomimetic substrate in order to demonstrate the effect of these events on cellular properties.It was observed that the cells that were grown for 15 days on the nanofibers,had majority of cells in the proliferative phase of cell cycle compared to TCPS.Moreover,these cells showed extensive collagen and fibronectin production.Due to these conditions C3H10T1/2 cells displayed higher cell internalization of BSA-AuNCs.Overall,this study indicates that the nano-topographical and biochemical environment could alter the cell proliferative behaviour and ECM production,which affects the cell internalization of BSA-AuNCs.Also,PCL-chitosan nanofibrous substrate could be a better alternative to TCPS for cell culture studies.展开更多
文摘Severe blood loss due to traumatic injuries remains one of the leading causes of death in emergency settings.Chitosan continues to be the candidate material for hemostatic applications due to its inherent hemostatic properties.However,available chitosan-based dressings have been reported to have an acidic odor at the wound site due to the incorporation of acid based solvents for their fabrication and deformation under compression owing to low mechanical strength limiting its usability.In the present study semi-IPN cryogel was fabricated via Schiff's base cross-linking between the polyaldehyde groups of oxidized dextran and thiolated chitosan in presence of locust bean gum(LBG)known for its hydrophilicity.Polymerization at12C yielded macroporous semi-IPN cryogels with an average pore size of 124.57±20.31 mm and 85.46%porosity.The hydrophobicity index of LBG reinforced semi-IPN cryogel was reduced 2.42 times whereas the swelling ratio was increased by 156.08%compare to control cryogel.The increased hydrophilicity and swelling ratio inflated the compressive modulus from 28.1 kPa to 33.85 for LBG reinforced semi-IPN cryogel.The structural stability and constant degradation medium pH were also recorded over a period of 12 weeks.The cryogels demonstrated lower adsorption affinity towards BSA.The cytotoxicity assays(direct,indirect)with 3T3-L1 fibroblast cells confirmed the cytocompatibility of the cryogels.The hemolysis assay showed<5%hemolysis confirming blood compatibility of the fabricated cryogel,while whole blood clotting and platelet adhesion assays confirmed the hemostatic potential of semi-IPN cryogel.
文摘Biomimetic cell culture substrates are developed as an alternative to the conventional substrates.They provide necessary biochemical and biophysical cues to the cells from their surrounding environment for their optimal growth,behaviour and physiology.Changes in physiology of cells growing on biomimetic substrate can essentially affect results of in vitro biological experiments such as drug cytotoxicity,nanoparticle internalization or signalling pathways.As majority of ECM proteins are fibrous in nature,nanofibrous scaffolds have more biomimicking properties.Therefore,in this study,we developed ECM mimicking polycaprolactone-chitosan nanofiber substrate and evaluated its effect on cell morphology,proliferation,cell cycle and ECM production.Further,cellular uptake of BSA-AuNCs has been assessed on conventional and biomimetic substrate in order to demonstrate the effect of these events on cellular properties.It was observed that the cells that were grown for 15 days on the nanofibers,had majority of cells in the proliferative phase of cell cycle compared to TCPS.Moreover,these cells showed extensive collagen and fibronectin production.Due to these conditions C3H10T1/2 cells displayed higher cell internalization of BSA-AuNCs.Overall,this study indicates that the nano-topographical and biochemical environment could alter the cell proliferative behaviour and ECM production,which affects the cell internalization of BSA-AuNCs.Also,PCL-chitosan nanofibrous substrate could be a better alternative to TCPS for cell culture studies.
