Comprehensive spectroscopic studies of synergism between Gadong starch based carbon dots and bovine serum albumin

Spectrochim Acta A Mol Biomol Spectrosc. 2019 Jul 5:218:85-96. doi: 10.1016/j.saa.2019.03.108. Epub 2019 Mar 29.

Abstract

Carbon dots (C-dots) were used to study the binding mechanisms with serum protein, bovine serum albumin (BSA) by using two notable binding systems known as non-covalent and covalent interaction. Interaction between C-dots and BSA were estimated by Stern-Volmer equation and Double Log Regression Model (DLRM). According to the fluorescent intensity, quenching of model carrier protein by C-dots was due to dynamic quenching for non-covalent and static quenching for covalent binding. The binding site constant, KA and number of binding site, for covalent interaction is 1754.7L/mol and n≈1 (0.6922) were determined by DLRM on fluorescence quenching results. The blue shift of the fluorescence spectrum, from 450nm to 421nm (non-covalent) and 430nm (covalent) and suggested that both the microenvironment of C-dots and protein changed in relation to the protein concentration. The fluorescence intensity results show that protein structure has a significant role in Protein-C-dots interactions and type of binding influence physicochemical properties of C-dots differently. Understanding to this bio interface is important to utilize both quantum dots and biomolecules for biomedical field. It can be a useful guideline to design further applications in biomedical and bioimaging.

Keywords: Binding interaction; Bovine serum albumin; C-dots; Fluorescence quenching; Quantum dots.

MeSH terms

  • Animals
  • Binding Sites
  • Carbon / chemistry
  • Carbon / metabolism*
  • Cattle
  • Immobilized Proteins / chemistry
  • Immobilized Proteins / metabolism
  • Molecular Docking Simulation
  • Protein Binding
  • Quantum Dots / chemistry
  • Quantum Dots / metabolism*
  • Quantum Dots / ultrastructure
  • Serum Albumin, Bovine / chemistry
  • Serum Albumin, Bovine / metabolism*
  • Spectrometry, Fluorescence
  • Spectrophotometry, Ultraviolet
  • Starch / chemistry
  • Starch / metabolism
  • Thermodynamics

Substances

  • Immobilized Proteins
  • Serum Albumin, Bovine
  • Carbon
  • Starch