Spectroscopic Studies of CNT Induced Fibrillar Structures of BSA, Haemoglobin and Lysozyme

摘要

Nanotechnology has brought several innovations in the biomedical field due to the unique properties of nanoparticles (NPs) with the size range below 100 nm. But, there arise issues on the negative intervention of such NPs with human owing out from their interaction with biomolecules possessing significant biological function. For example, the pathogenesis of several amyloid diseases is mainly due to the conversion of proteins alpha helical contents to the insoluble aggregates of beta sheets structures arising out of their interaction with NPs. NPs may either inhibit or promote the aggregation of biomolecules. Herein, we have studied the fibrillation behavior of four significant biological macromolecules including the plasma protein Bovine Serum Albumin, iron transport protein such as the haemoglobin and the enzyme lysozyme from chicken egg white and human source as the model system to investigate the fibrillation effect of CNTs including the pristine SW, MW and the functionalized OH-MWCNTs. Turbidity, Congo Red (CR) and Thioflavin T (ThT) assay have shown the presence of fibrillar structures, 3D and tryptophan emission studies revealed the quenching effect. Fluorescence microscopic images of the fibrillar structures were also captured. Circular Dichroism studies revealed the quantitative estimation of the secondary structures of biomolecules in the fibrillation conditions. These results demonstrate the promoting effect of CNTs against the fibrillation of biomolecules induced in vitro.