CdxZn1-xS nanoparticles-protein corona: Kinetics and temperature dependent interaction along with detection of the denaturation and unfolding of serum albumin.

In this study, the interaction and corona formation of HSA with nanostructured CdxZn1-xS have been analysed through microscopic, spectroscopic and structural investigations. Binding kinetics showed corona formation time for CdS NRs, Cd0.5Zn0.5S NPs and ZnS NPs are 60,45,70 min, respectively. The observed time for surface reorganization (85,130,110 min) was greater than corona formation time (60, 45, 70 min, respectively). The HRTEM showed that during corona formation of HSA, CdS NRs are attached each other and Cd0.5Zn0.5S NPs leads aggregation of HSA through positive cooperative reaction at room temperature. Very small ZnS NPs (5-7 nm) were selectively formed protein corona on their surface and coronas were placed almost isolated way. During interaction process protein fibrillation occurs and some wrinkles were formed. The emission spectrums of nano-bio corona were studied within temperature ranges of 298-328 K, which indicated that the tertiary deformation and quenching depend on temperature with exothermic nature of bindings. The ultrafast decay showed that maximum energy transfer among HSA and CdS NRs, Cd0.5Zn0.5S NPs, ZnS NPs are 52.4, 37.4, 23.3 %, respectively. The unfolding of protein was occurs during interaction with gradual increment of the ratio of β-strand to α-helix of HSA from 0.13 to 4.28 due to interaction.