Multispectroscopic studies on the molecular interactions between bovine γ‐globulin and borohydride‐capped silver nanoparticles. (27th May 2022)

• Record Type: Journal Article
• Authors: Sharma, Anchal; Sarmah, Sharat; Roy, Atanu Singha; Ghosh, Kalyan Sundar
• Is Part Of: Luminescence. Volume 37:Number 7(2022)
• Page Start: 1200
• Page End: 1207
• Publication Date: 2022-05-27
• Subjects: 3D‐fluorescence -- borohydride‐capped silver nanoparticles -- bovine γ‐globulin -- circular dichroism -- fluorescence quenching; Luminescence -- Periodicals; Bioluminescence -- Periodicals; Chemiluminescence -- Periodicals; Luminescence -- Periodicals; 535.35
• DOI: 10.1002/bio.4276
• Languages: English
• ISSNs: 1522-7235

Abstract

Abstract: Interactions between bovine γ‐globulin (BGG) and borohydride‐capped silver nanoparticles (BAgNPs) were studied using dynamic light scattering (DLS) and spectroscopic techniques such as UV–vis spectroscopy, fluorescence, and circular dichroism. The results were compared with earlier reported interactions between γ‐globulin and citrate‐coated AgNPs (CAgNPs). BAgNPs were synthesized and characterized. Irrespective of the coating on AgNPs, nanoparticles had formed ground‐state complexes with the protein. CAgNPs, as well as BAgNPs had caused static quenching of tryptophan (Trp) fluorescence of the protein. The change in the capping agent from citrate to borohydride weakened the binding of nanoparticles with the protein. But the same change in capping agent had increased the fluorescence quenching efficiency of AgNPs. Hydrogen bonding and van der Waals interactions were involved in BGG–BAgNPs complex similar to the CAgNPs complex with γ‐globulin. Polarity of the Trp microenvironment in BGG was not altered using BAgNPs as opposed to CAgNPs, as supported using synchronous and three‐dimensional fluorescence. Resonance light scattering experiments also suggested nano‐bio conjugation. Far‐UV and near‐UV circular dichroism (CD) spectra respectively pointed towards changes in the secondary and tertiary structure of BGG by BAgNPs, which was not observed for CAgNPs. Abstract : Quenching of tryptophan fluorescence (left) and changes in 3D‐fluorescence (right) of bovine γ‐globulin on addition of borohydride‐capped silver nanoparticles.