title: Dual-signal amplified electrochemiluminescence immunoassay for salbutamol based on quantum dots and gold nanoparticle-labeled horseradish peroxidase.
abstract: This study describes a novel electrochemical immunosensor to amplify the electrochemiluminescence (ECL) signal for the ultrasensitive detection of salbutamol (SAL) using quantum dots (QDs) and gold nanoparticle (AuNP) conjugated horseradish peroxidase (HRP). The electrochemical detection was based on the HRP catalyzed consumption of self-produced H2O2, which has been extensively used as a co-reactant of QDs, by o-phenylenediamine (OPD). The enzymatic reaction rate is proportional to the amount of HRP bound to the electrode. In the presence of a SAL standard solution, the immobilized SAL coating antigens competed with the SAL solution for the Ab-AuNPs-HRP complexes. With an increase in the SAL concentration, the amount of immobilized HRP decreases, which leads to an increase in the ECL intensity. Under optimized conditions, the ECL intensity changes linearly with the logarithm of the SAL concentration in the range of 0.05-500 ng mL(-1) with a detection limit of 0.017 ng mL(-1) (S/N = 3). The ECL immunosensor possesses high sensitivity, satisfactory reproducibility and selectivity, and may provide a feasible route for practical application.
authors.affiliation: College of Chemistry, Chemical Engineering & Materials Science, Soochow University, Suzhou 215123, China. lijgsd@suda.edu.cn denganping@suda.edu.cn.
authors.forename: Fudong
authors.initials: F
authors.lastname: Cai
authors.forename: Nan
authors.initials: N
authors.lastname: Wang
authors.forename: Tiantian
authors.initials: T
authors.lastname: Dong
authors.forename: Anping
authors.initials: A
authors.lastname: Deng
authors.forename: Jianguo
authors.initials: J
authors.lastname: Li
mesh_terms: D000420:Albuterol / Q000032:analysis* / Q000276:immunology; D000818:Animals; D055910:Antibodies, Immobilized / Q000737:chemistry / Q000276:immunology; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D006046:Gold / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry / Q000378:metabolism*; D007118:Immunoassay; D057230:Limit of Detection; D008099:Liver / Q000378:metabolism; D008163:Luminescent Measurements / Q000379:methods*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D045663:Quantum Dots / Q000737:chemistry* / Q000648:ultrastructure; D013552:Swine
chemical_list: D055910:Antibodies, Immobilized; D004800:Enzymes, Immobilized; D006046:Gold; D006735:Horseradish Peroxidase; D000420:Albuterol