Qing Zhua, Huixia Liua, Jing Zhangc, Kang Wub, * （吴康）, Anping Denga *（邓安平）, Jianguo Lia, *（李建国）
a The Key Lab of Health Chemistry & Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering & Materials Science, Soochow University, Suzhou 215123, China
b School of Biology & Basic Medical Science, Soochow University, Suzhou 215123, China
c Shanghai Animal Disease Control Center, Shanghai 201103, China
Sensors and Actuators B 243 (2017) 121–129
In this work, gold nanoparticals (AuNPs) and CdSe QDs decorated poly (diallyldimethylammonium chloride)-graphene (CdSe QDs/PDDA-GN/AuNPs) were prepared and applied as probe to assemble an electrochemiluminescence (ECL) immunosensor for detecting ractopamine (RAC) for the first time. The CdSe QDs/PDDA-GN/AuNPs composite showed good electronic conductivity, fast response and satisfactory stability which employed for fabricating ECL biosensors with high sensitivity. AuNPs and PDDA-GN were creatively applied in this sensor not only accelerate electron conduction to achieve dual signal amplification, but also provide large surface for coating antigen and antibody loading. A competitive immunoassay strategy was chosen for determining RAC, where RAC in the sample would compete with the coating antigen for the limited biomarkers. The well-prepared ECL immunosensor satisfied in samples detection of RAC with a wider linear range from 0.01 to 1000 ng mL−1 and a lower detection limit of 2.6 pg mL−1 (S/N = 3). The proposed ECL immunosensor displayed high sensitivity and stability, and provided an approach for determining other important biomarkers.
链接：http://www.sciencedirect.com/science/article/pii/S0925400516319335