Deciphering the Interactions of Bromelain with Carbon Nanotubes: Role of Protein as Well as Carboxylated Multiwalled Carbon Nanotubes in a Complexation Mechanism

Abstract

The interaction of the carboxylated multiwalled carbon nanotubes (MCNTCOOH) with globular protein bromelain (BM) has been studied using various spectroscopic and biophysical techniques. BM exhibited decreased stability in the presence of MCNTCOOH compared to BM in buffer. Additionally, the morphological changes in BM were decoded using a field emission scanning electron microscope (FESEM). Additionally, the increase in the size (hydrodynamic radius, dH) of MCNTCOOH as a result of BM adsorption was analyzed using dynamic light scattering (DLS). From this study, it was determined that the interaction of BM with MCNTCOOH results in a complex formation between the fluorophore and the quencher. In addition to hydrophobic and π–π interactions, electrostatic interactions a play vital role as the interacting force between BM and MCNTCOOH. Additionally, the DLS results revealed that a high concentration of BM can induce MCNTCOOH aggregations, which are reversible in nature. These results have helped in understandi...