Facile, sensitive and selective fluorescence turn-on detection of HSA/BSA in aqueous solution utilizing 2,4-dihydroxyl-3-iodo salicylaldehyde azine

A novel fluorescence turn-on detection method of human serum albumin (HSA) and bovine serum albumin (BSA) in aqueous solution is investigated using 2,4-dihydroxyl-3-iodo salicylaldehyde azine (DISA). Upon the addition of DISA to HSA/BSA solution, a fluorescence turn-on effect at 529 nm can be observed with a large stokes shift of similar to 129 nm based on hydrophobic binding-mode between protein and dye Under the optimal condition, the linear ranges of fluorescence intensity for HSA and BSA are 0.1-30 mu g mL(-1) with the relative correlation coefficient of R-2 = 0.991 (n =10) and 0.3-50 mu g mL(-1) with R-2 = 0 997 (n = 10): and the detection limits for HSA and BSA based on IUPAC (C-DL =3.5(b)/m) are 20 ng m L-1 and 50 ng mL(-1), respectively (C) 2009 Elsevier B.V. All rights reserved.