A flow-injection chemiluminescence method for the determination of human serum albumin, using the reaction of fluorescein-human serum albumin-sodium hypochlorite by the enhancement effect of the cationic surfactant cetyltrimethylammonium bromide.
The interaction between surfactant and fluorescein was studied, using a fluorescence spectroscopy and flow-injection (FI) chemiluminescence (CL) method. It was found that the cationic surfactant cetyltrimethylammonium bromide (CTAB) could cause the structural transformation of fluorescein from the quinone to the spirolactone form, and greatly enhance the CL intensity of the fluorescein-human serum albumin (HSA) complex. Based on this finding, a rapid and sensitive FI-CL method was developed for the determination of HSA. Under the optimum conditions, the proposed method has a linear range of 0.05-24.0 microg/mL, with a detection limit of 0.03 microg/mL for HSA (3sigma). The relative standard deviation (RSD) of 1.2 microg/mL HSA (n = 8) is 0.8%. The method was applied to the determination of protein content in urine samples, with satisfactory results. Density functional theory was used to study the mechanism of surfactant-enhanced CL intensity of the fluorescein-HSA complex.
Huang
Chun-Bao
CB
School of Chemistry and Applied Chemistry, Huanggang Normal University, Huangzhou 438000, People's Republic of China. huacb2003@yahoo.com.cn
Zhang
Kai
K
Liu
Xue-Lian
XL
Wang
Sheng-Fu
SF
D002412:Cations; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry*; D017022:Flow Injection Analysis / Q000295:instrumentation / Q000379:methods; D019793:Fluorescein / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008163:Luminescent Measurements / Q000295:instrumentation / Q000379:methods*; D015394:Molecular Structure; D012680:Sensitivity and Specificity; D012709:Serum Albumin / Q000032:analysis*; D012973:Sodium Hypochlorite / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry*
D002412:Cations; D002593:Cetrimonium Compounds; D012709:Serum Albumin; D013501:Surface-Active Agents; D012973:Sodium Hypochlorite; D019793:Fluorescein; D000077286:Cetrimonium