Development of D-π-A organic dyes for discriminating HSA from BSA and study on dye-HSA interaction

• Published in: Bioorganic chemistry 2024-06, Vol.147, p.107360-107360, Article 107360
• Main Authors: Cao, Hao-Wen, Chen, Yan-Song, Li, Jing-Zhi, Chen, Hai-Wen, Li, Lu-Yu, Li, Ze-Kai, Wang, Ming-Qi
• Format: Article
• Language: English
• Subjects: Animals; Biological fluid; Cattle; D-π-A constitution; Fluorescent Dyes - chemical synthesis; Fluorescent Dyes - chemistry; Fluorescent probe; Human serum albumin; Humans; Molecular Structure; Selectivity; Serum Albumin, Bovine - chemistry; Serum Albumin, Bovine - metabolism; Serum Albumin, Human - chemistry; Serum Albumin, Human - metabolism; Spectrometry, Fluorescence
• ISSN: 0045-2068; 1090-2120
• DOI: 10.1016/j.bioorg.2024.107360

[Display omitted] •D-π-A fluorescent probes were reasonably designed and developed through systematic changes in electron-donor and-acceptor groups.•Probes M−H−SO3with a hydrophilic sulfonate group displayed sufficient selectivity for discrimination of HSA from BSA.•Probe M−H−SO3 can bind to the IB site of HSA, yielding a substantial fluorescent enhancement.•The probe M−H−SO3 can be used for detecting human serum albumin in urine samples. HSA (human serum albumin), a most abundant protein in blood serum, plays a key role in maintaining human health. Abnormal HSA level is correlated with many diseases, and thus has been used as an essential biomarker for therapeutic monitoring and biomedical diagnosis. Development of small-molecule fluorescent probes allowing the selective and sensitive recognition of HSA in in vitro and in vivo is of fundamental importance in basic biological research as well as medical diagnosis. Herein, we reported a series of new synthesized fluorescent dyes containing D-π-A constitution, which exhibited different optical properties in solution and solid state. Among them, dye M−H−SO3 with a hydrophilic sulfonate group at electron-acceptor part displayed selectivity for discrimination of HSA from BSA and other enzymes. Upon binding of dye M−H−SO3 with HSA, a significant fluorescence enhancement with a turn-on ratio about 96-fold was triggered. The detection limit was estimated to be ∼ 40 nM. Studies on the interaction mechanism revealed that dye M−H−SO3 could bind to site III of HSA with a 1:1 binding stoichiometry. Furthermore, dye M−H−SO3 has been applied to determine HSA in real urine samples with good recoveries, which provided a useful method for HSA analysis in biological fluids.