Fluorescent probe for simultaneous detection of human serum albumin and sulfite: A theoretical analysis

• Published in: Journal of molecular structure 2022-05, Vol.1255, p.132441, Article 132441
• Main Authors: Liu, Yu-ling, Huang, He, Peng, Yong-jin
• Format: Article
• Language: English
• Subjects: Density functional theory; Electronic properties; Fluorescent probe; HSA
• ISSN: 0022-2860; 1872-8014
• DOI: 10.1016/j.molstruc.2022.132441

•The different stable conformations of probe C23 were found through theoretical method which explained the no fluorescent character of the probe itself.•The extreme points of electrostatic potential of C23 indicated the potential reaction sites with the HSA and SO2.•After the Michael addition reaction with SO2 (HSO3−1), some rotated CC bonds in C23 were restricted in CS structure reduced the number of the stable conformations and led to the blue fluorescence generation which was proved by theoretical research.•The electron excitation analysis indicated the charge transfer process in the C23 and CS when the molecules were under optical excitation. A small molecule probe for simultaneous detection of Human Serum Albumin (HSA) and Sulfite via distinct fluorescent signals was designed recently. This effective tool provided a significant opportunity to understanding the underlying mechanism of synergistic action between sulfite and HSA in disease. The structural and fluorescent characters of this probe molecule were studied under density functional theory in this work. The different stable conformations of probe C23 were found through theoretical method which can explain the negative experimental fluorescent character of the probe itself. The electron excitation analysis indicated the charge transfer process in the restricted probe C23 (binding to the hydrophobic cavity of HSA) and probe CS (C23 reaction with sulfite) when the molecules were under optical excitation. The theoretical results could be helpful for understanding the electronical properties in the probe and providing the insights for designing new functional probe molecules.