CdSe/ZnS quantum dots based electrochemical immunoassay for the detection of phosphorylated bovine serum albumin.
A CdSe/ZnS quantum dot (QD) based electrochemical immunoassay of phosphorylated bovine serum albumin (BSA-OP) as a protein biomarker is presented. The QDs were used as labels for amplifying electrochemical signals and were conjugated with a secondary anti-phosphoserine antibody in a heterogeneous sandwich immunoassay. In this assay, the model phosphorylated protein BSA-OP was added to the primary BSA antibody coated polystyrene microwells, and then the QD labeled anti-phosphoserine antibody was added for completing immunorecognition. Finally, the bound QD was dissolved in an acid-dissolution step and was detected by electrochemical stripping analysis. The measured current responses were proportional to the concentration of BSA-OP. Under optimal conditions, the voltammetric response was linear over the range of 0.5-500 ngmL(-1) of BSA-OP, with a detection limit of 0.5 ngmL(-1). It also shows good reproducibility with a relative standard deviation of 8.6%. This QD-based electrochemical immunoassay offers great promise for simple and cost-effective analysis of protein biomarkers.
Pinwattana
Kulwadee
K
Department of Chemistry, Faculty of Science, Chulalongkorn University, Patumwan, Bangkok 10330, Thailand.
Wang
Jun
J
Lin
Chiann-Tso
CT
Wu
Hong
H
Du
Dan
D
Lin
Yuehe
Y
Chailapakul
Orawon
O
D000818:Animals; D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D002417:Cattle; D055664:Electrochemical Techniques; D007118:Immunoassay / Q000379:methods; D046529:Microscopy, Electron, Transmission; D058726:Nanoconjugates / Q000737:chemistry / Q000648:ultrastructure; D010766:Phosphorylation; D010768:Phosphoserine / Q000737:chemistry / Q000276:immunology; D045663:Quantum Dots; D015203:Reproducibility of Results; D012710:Serum Albumin, Bovine / Q000032:analysis* / Q000737:chemistry / Q000276:immunology
D000911:Antibodies, Monoclonal; D058726:Nanoconjugates; D010768:Phosphoserine; D012710:Serum Albumin, Bovine