已发表论文

使用 4-巯基苯酸/生物素修饰的多功能纳米金为标记物对糖蛋白进行放大伏安检测

 

Authors Liu L, Xing Y, Zhang H, Liu RL, Liu HJ, Xia N

Published Date May 2014 Volume 2014:9(1) Pages 2619—2626

DOI http://dx.doi.org/10.2147/IJN.S62343

Received 12 February 2014, Accepted 23 March 2014, Published 27 May 2014

 
Abstract: Ultrasensitive detection of protein biomarkers is essential for early diagnosis and therapy of many diseases. Glycoproteins, differing from other types of proteins, contain carbohydrate moieties in the oligosaccharide chains. Boronic acid can form boronate ester covalent bonds with diol-containing species. Herein, we present a sensitive and cost-effective electrochemical method for glycoprotein detection using 4-mercaptophenylboronic acid (MBA)/biotin-modified gold nanoparticles (AuNPs) (MBA-biotin-AuNPs) as labels. To demonstrate the feasibility and sensitivity of this method, recombinant human erythropoietin (rHuEPO) was tested as a model analyte. Specifically, rHuEPO was captured by the anti-rHuEPO aptamer-covered electrode and then derivatized with MBA-biotin-AuNPs through the boronic acid–carbohydrate interaction. The MBA-biotin-AuNPs facilitated the attachment of streptavidin-conjugated alkaline phosphatase for the production of electroactive p-aminophenol from p-aminophenyl phosphate substrate. A detection limit of 8 fmol L-1 for rHuEPO detection was achieved. Other glycosylated and non-glycosylated proteins, such as horseradish peroxidase, prostate specific antigen, metallothionein, streptavidin, and thrombin showed no interference in the detection assay.
Keywords: electrochemical biosensor, boronic acid, signal amplification, alkaline phosphatase