title: Amplified voltammetric detection of glycoproteins using 4-mercaptophenylboronic acid/biotin-modified multifunctional gold nanoparticles as labels.
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.
authors.affiliation: College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan, People's Republic of China ; College of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan, People's Republic of China.
authors.forename: Lin
authors.initials: L
authors.lastname: Liu
authors.affiliation: College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan, People's Republic of China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Xing
authors.affiliation: College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan, People's Republic of China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.affiliation: College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan, People's Republic of China.
authors.forename: Ruili
authors.initials: R
authors.lastname: Liu
authors.affiliation: College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan, People's Republic of China.
authors.forename: Huijing
authors.initials: H
authors.lastname: Liu
authors.affiliation: College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan, People's Republic of China ; College of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan, People's Republic of China.
authors.forename: Ning
authors.initials: N
authors.lastname: Xia
mesh_terms: D000669:Amplifiers, Electronic; D015374:Biosensing Techniques / Q000295:instrumentation*; D001710:Biotin / Q000737:chemistry* / Q000276:immunology; D001897:Boronic Acids / Q000737:chemistry*; D003217:Conductometry / Q000295:instrumentation*; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006023:Glycoproteins / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D006046:Gold / Q000737:chemistry*; D007118:Immunoassay / Q000295:instrumentation; D053768:Metal Nanoparticles / Q000737:chemistry*; D013194:Staining and Labeling; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: C510906:4-mercaptophenylboronic acid; D001897:Boronic Acids; D006023:Glycoproteins; D013438:Sulfhydryl Compounds; D001710:Biotin; D006046:Gold
keywords: alkaline phosphatase; boronic acid; electrochemical biosensor; signal amplification