Biophysical study of cisplatin loaded albumin-gold nanoparticle and its interaction with glycans of gp60 receptor.

The biophysical study provides a quantitative understanding of biomolecular interaction. The interaction of protein-nanoparticle has been critically examined using various biophysical and biochemical tools. The present investigation focussed on the biophysical characterization of anticancer drug cisplatin (CPT) with Bovine Serum Albumin (BSA) - Gold nanoparticles (GNP) conjugate; and BSA-CPT-GNP interaction with glycan sugars of glycoprotein receptor. Spectroscopic study (UV visible and fluorescence) showed strong binding of CPT loaded BSA with GNP. The binding between BSA-CPT-GNP and glycan sugars of gp60 receptor was estimated. Circular Dichroism (CD) spectroscopy study revealed weak alteration in the secondary structure of BSA upon CPT and GNP binding. Dynamic Light Scattering (DLS) data indicated the changes in the size of conjugates; zeta potential data showed the stability of conjugates. Biocompatible studies showed no toxicity to RBCs and chorioallantoic membrane (CAM). The mechanisms of interaction have been explored at the molecular and cellular levels. This investigation can be effectively extrapolated for in-vivo and in-vitro targeted drug delivery studies for cancer therapy.

Effect of Smartphone Light Fluxes on Cornea: A Biophysical Study.

OBJECTIVE: Biophysical study to investigate (a) the effects of smartphone light fluxes (SPLF) on isolated mammalian cornea and model protein (insulin), (b) to predict the possible visual interference of SPLF. MATERIALS AND METHODS: Fresh goat cornea and insulin protein were used as an experimental model system. The energy of absorbed SPLF was measured using chemical dosimeter. The effect of SPLF on the aggregation of model protein was studied using fluorescence spectroscopy and dynamic light scattering (DLS). Fluorescence microscopy, scanning electron microscopy (SEM), DLS, were used for cornea imaging. RESULTS: The spectral emission peak of SPLF was observed at 380 nm and 420 nm. Absorbed radiation of SPLF was found to be 2.82 mWm-2 and 1.92 mWm-2 for collimated (focussed) and noncollimated (nonfocussed) condition, respectively. Secondary structural changes of insulin were observed by fluorescence and zeta potential after SPLF exposure. SEM study revealed the disorganization of the epithelial cell surface, increase in intercellular space, disorganization of primary epithelium layer, and exposure of the second layer is seen in depth. Differential Interference Microscopy showed an optical gradient in images that appears to be changed in specimen structure. Fluorescence microscopy showed disorganization in epithelial cell pattern. A significant difference in bio-molecular permeation was observed in the exposed cornea. Ultraviolet UV-visible spectroscopy study indicated a reduction in light transmission through the cornea. CONCLUSIONS: The obtained results indicate changes in physicochemical and morphological modifications in the cornea and insulin modifications after exposed to SPLF.

Biophysical interactions between silver nanoparticle-albumin interface and curcumin.

Active targeted drug delivery methods facilitate effective uptake of functionalized nanoparticles through receptor-mediated transcytosis. In recent years, albumin-nanoparticle interaction has been critically examined so that this functionalized nanoparticle can be efficiently loaded with drugs. The present investigation aims at understanding the adsorption of Bovine Serum Albumin (BSA) on Silver Nanoparticle (SNP) surface, preparation of soft conjugates (SC) and hard conjugates (HC) of BSA-functionalized SNP (SNP-BSA), and their interaction with curcumin (CUR). HC contains tightly bound BSA whereas SC involves tightly and loosely bound BSA. Increase in the hydrodynamic radii of conjugates was observed upon SNP incubation with increased concentration of BSA. Three different SNP-BSA conjugate ratios were selected to study their interaction with CUR. Fluorescence spectroscopy showed a strong association between CUR and SNP:BSA conjugates. However, binding varied with a change in the conjugate ratio. Circular Dichroism (CD)/Fourier Transform Infrared (FTIR) spectroscopy revealed the alterations in the secondary structure of BSA upon CUR binding to the conjugates. Zeta potential data indicated stable conjugate formation. CUR in SNP:BSA conjugate was found to have a higher half-life as compared to the control. We believe that this is the first biophysical characterization report of conjugates that can be effectively extrapolated for targeted drug delivery.