Selective detection of human serum albumin by near infrared emissive fluorophores: Insights into structure-property relationship

Abstract

Two donor-acceptor fluorophores were prepared and tested for quantitative determination of HSA in aqueous samples. Fluorophores were non-emissive in polar solvents due to energy loss via nonradiative decays. Complexation of the fluorophores with HSA resulted multi-fold enhancement of emission in the red-near infrared (NIR) region. The emission intensity was linearly correlated to the amount of protein in the solution, which enabled us to develop calibration graphs for quantitative estimation of HSA in synthetic urine samples. Between the two fluorophores, the methoxy substituted fluorophore 1 selectively recognized HSA. It exhibited remarkable fluorescence enhancement with HSA over bovine serum albumin (BSA) and other globular proteins. The selective sensing aptitude of 1 was attributed to its restricted motions in the protein's microenvironment due to multiple non-covalent interactions, preventing energy loss by radiationless decay. The different recognition properties of the fluorophores were estimated by the steady-state fluorescence and molecular docking studies. These findings indicate that this class of fluorophores can be useful for quantitative estimation of HSA in biological urine and blood samples in clinical practice.

Anti-human albumin monoclonal antibody immobilized on EDC-NHS functionalized carboxylic graphene/AuNPs composite as promising electrochemical HSA immunosensor

“…The main functions of albumin include maintaining the osmotic pressure in the plasma, the transfer of fatty acids, steroids, hormones and certain drugs [1]. Normally, the concentration of HSA in serum is 35-50 g/L and less than 20 mg/L in urine of healthy persons [2,3]. However, these values can significantly deviate in the case of some diseases or metabolic disorders [4].…”

Development of Human Serum Albumin Selective Fluorescent Probe Using Thieno[3,2-b]pyridine-5(4H)-one Fluorophore Derivatives

“…In comparison with other detection methods, fluorescent probes are favored because of advantages including a rapid, non-invasive, and sensitive response. Accordingly, several fluorescent probes have been reported using many different types of fluorophore such as tetraphenylethylene, squaraine dye, and indolium derivative, which is based on aggregation-induced emission (AIE), molecular rotor containing donor-π-acceptor (D-π-A) structured fluorophore, and self-assembled nanoparticles [22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37]. However, there remain some problems to be solved, such as the low sensitivity and selectivity toward HSA.…”

A novel three-position molecular switch based on the transformations of a cyano-substituted pyrrol-2-one derivative

“…In the most cases, TCF derivatives are intensely colored compounds due to various unsaturated substituents conjugated with the BDTC fragment. There are such two-position molecular switches as hydrazones A, [12][13][14] 4-hydroxy derivatives B 15,16 and 2-hydroxy derivatives C among them. Contrasting color change is achieved by the action of acid-base reagents on compounds A and B, and by visible light irradiation on compounds C. [17][18][19] There is also a single example of a three-position switch C showing a combination of pH sensitivity and photochromic properties.…”