Electrospun protein nanofibers in healthcare: A review.

Electrospun nanofibers are being utilized for a wide range of healthcare applications. A plethora of natural and synthetic polymers are exploited for their ability to be electrospun and replace the complex habitat provided by the extracellular matrix for the cells. The fabrication of nanofibers can be tuned to act as a multicarrier system to deliver drugs, growth factors and health supplements etc. in a sustained manner. Owing to its pliability, nanofibers reached its heights in tissue engineering and drug delivery applications. This review mainly focuses on various standardized parameters and optimized blending ratios for animal and plant proteins to yield fine, continuous nanofibers for effective utilization in various healthcare applications.

Effect of bimetallic iron:zinc nanoparticles on collagen stabilization.

The ability of metallic nanoparticles to facilitate crosslinking of collagen by binding to side chain moieties has been studied for some time. The current study is mainly focused on understanding the effect of bimetallic iron:zinc nanoparticles on the stability of collagen. The results showed that the bimetallic nanoparticle was able to efficiently stabilize collagen, which is reflected by the enhanced fibril formation kinetics, viscosity, mechanical and thermal stability of the collagen molecule crosslinked with bimetallic nanoparticles. Contrary to the inhibitory effects on these properties exhibited by individual nanoparticles, in combination as bimetallic nanoparticles they showed superior collagen crosslinking properties. It was observed that the physico-chemical properties of the individual nanoparticles drastically change when they are combined with other metal nanoparticles and these properties are entirely different from the properties they exhibit individually. Circular dichroism analysis confirmed no structural disparity in collagen despite the superior physicochemical properties suggesting the significance of bimetallic iron:zinc nanoparticle mediated crosslinking. The ability of the bimetallic iron:zinc nanoparticles to crosslink collagen molecules suggested that the bimetallic iron:zinc nanoparticles apart from their application in tissue engineering could find use in tanning of leather. Superior stabilization of collagen by bimetallic Fe:Zn nanoparticles when compared to chrome tanning therefore may reduce the amount chromium used in leather tanning process. The present study is the first report on the application of a bimetallic nanoparticle as crosslinker for stabilisation of collagen and its application as an ecofriendly tanning agent in the leather industry. This study gives new scope for the application of bimetallic nanoparticle-based strategies for the development of alternative crosslinking agents for tissue engineering applications.

Effect of Cr(VI) and Ni(II) metal ions on human adipose derived stem cells.

Environmental exposure of Cr(VI) and Ni(II) due to rapid industrialization causes adverse effects in living tissues. Small quantities of these ions also find their way into tissues when metal alloys are used as implants. Even though considerable research has been done on the effects due to their exposure in animal cells, there are only very few reports on how they can affect stem cells which have been shown to be found in adult tissues as well, albeit in small quantities. Hence this study was aimed at understanding how Cr(VI) and Ni(II) affect human adipose derived stem cells (hADSCs) in a cell culture environment. Our results indicate that both ions induce apoptosis in a concentration and time dependent manner with loss of mitochondrial membrane potential (MMP) and corresponding increase in caspase-3 activity. With regard to Ni(II), apoptosis seems to occur only in a small percentage of cells while necrosis is predominant. It can be inferred that the long term exposure of these metals may cause adverse effects in stem cell proliferation and differentiation.