The Synthesis Of Low-Molecule Fluorescent Probes And Their Applications In The Detection Of Sugars And Serum Albumin

Fluorescence method has attracted wide attention due to its high sensitivity, good selectivity and rapid response. In this work, two kinds of organic fluorescent probes were designed and synthesized for selective detection of sugars and serum albumin.Four fluorescent probes for saccharides were designed based on the principle of covalently reversible combination between boronic acid and diols. Compounds CSP1-2are ICT probes with coumarin as the fluorophore. The emission maxima of both CSP1(616nm) and CSP2(632nm) are in the visible wavelength region with a Stokes shift of about150nm, which ensures both compounds potential probes for biological application. In PBS, significant fluorescence enhancements of CSP1-2were observed upon the addition of some saccharides. CSP1showed relatively high sensitivity towards D-fructose and.D-sorbitol, and their respective detection limits were0.05mmol/L and0.10mmol/L with CPS1as the probe.NSP1-2are PET probes with naphthalimide as the fluorophore. n-Butyl amine and ethanol amine were respectively introduced into NSP1and NSP2to improve the solubility of the probes. The presence of D-fructose induced about50times enhancement in the fluorescence of NSP2. The detection limits of fructose and sorbitol are0.045mmol/L and0.028mmol/L, respctively. NSP2was also used to detect the fructose content in drinks and the recovery was about85%, which suggests the application of NSP2in realistic samples.Fluorescent probes CPP1-3with coumarin as the fluorophore were designed and synthesized for the determination of bovine serum albumin (BSA). All three probes exhibited evidently solvatochromic UV-vis and fluorescence spectra. CPP3was the most effective towards the solvent’s polarity:155nm red shift in the emission maximum was found as the solvent changing from cyclohexane to phosphate buffer solution. CPP3was applied to detect BSA and the detection limit of BSA was0.6μg/mL with CPP3as the probe, which ensured the detection of BSA content in fetal bovine serum with good recovery.