title: A novel mimetic enzymatic fluorescence immunoassay for hepatitis B surface antigen by using a thermal phase separating polymer.
abstract: Iron tetrasulfonatophthalocyanine (FeTSPc), a peroxidase mimic, was used as a labeling reagent and poly(N-isopropylacrylamide) (PNIP) as the separation support of the immune complex for the mimetic-enzymatic immunoassay of hepatitis B surface antigen (HBsAg). PNIP was precipitated from aqueous solution when the ambient temperature was higher than its lower critical solution temperature of 31 degrees C. In a sandwich immunoassay, the antigen (HBsAg) first reacted with mouse anti-human HBsAg antibody immobilized on PNIP (PNIP-antibody) and then further reacted with FeTSPc-labeled mouse anti-HBsAg antibody (antibody-FeTSPc) at room temperature in a homogeneous format. After changing the temperature to separate the PNIP-antibody-HBsAg-antibody-FeTSPc conjugate moiety, it was re-dissolved and determined by coupling with the fluorogenic reaction of hydrogen peroxide and p-hydroxyphenylpropionic acid. The sensitivity of this method (3 ng mL-1) was close to that of the traditional ELISA using the same reactants. However, the assay was much faster (the assay time decreased from 100-120 to 45 min). This method was applied to determine HBsAg in human serum with satisfactory results.
authors.affiliation: Key Laboratory of Analytical Sciences of MOE and Department of Chemistry, Xiamen University, Xiamen 361005, China.
authors.forename: Q Z
authors.initials: QZ
authors.lastname: Zhu
authors.forename: H H
authors.initials: HH
authors.lastname: Yang
authors.forename: D H
authors.initials: DH
authors.lastname: Li
authors.forename: Q Y
authors.initials: QY
authors.lastname: Chen
authors.forename: J G
authors.initials: JG
authors.lastname: Xu
mesh_terms: D006514:Hepatitis B Surface Antigens / Q000097:blood*; D006801:Humans; D007124:Immunoenzyme Techniques; D013050:Spectrometry, Fluorescence
chemical_list: D006514:Hepatitis B Surface Antigens