title: Mass spectrometry signal amplification for ultrasensitive glycoprotein detection using gold nanoparticle as mass tag combined with boronic acid based isolation strategy.
abstract: We describe a novel method for rapid and ultrasensitive detection of intact glycoproteins without enzymatic pretreatment which was commonly used in proteomic research. This method is based on using gold nanoparticle (AuNP) as signal tag in laser desorption/ionization mass spectrometry (LDI-MS) analysis combined with boronic acid assisted isolation strategy. Briefly speaking, target glycoproteins were firstly isolated from sample solution with boronic acid functionalized magnetic microparticles, and then the surface modified gold nanoparticles were added to covalently bind to the glycoproteins. After that, these AuNP tagged glycoproteins were eluted from magnetic microparticles and applied to LDI-MS analysis. The mass signal of AuNP rather than that of glycoprotein was detected and recorded in this strategy. Through data processing of different standard glycoproteins, we have demonstrated that the signal of AuNP could be used to quantitatively represent glycoprotein. This method allows femtomolar detection of intact glycoproteins. We believe that the successful validation of this method on three different kinds of glycoproteins suggests the potential use for tracking trace amount of target glycoproteins in real biological samples in the near future.
authors.affiliation: Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, Shanghai, China.
authors.forename: Minbo
authors.initials: M
authors.lastname: Liu
authors.forename: Lijuan
authors.initials: L
authors.lastname: Zhang
authors.forename: Yawei
authors.initials: Y
authors.lastname: Xu
authors.forename: Pengyuan
authors.initials: P
authors.lastname: Yang
authors.forename: Haojie
authors.initials: H
authors.lastname: Lu
mesh_terms: D001897:Boronic Acids / Q000737:chemistry; D002364:Caseins / Q000032:analysis; D045304:Cytochromes c / Q000032:analysis; D006023:Glycoproteins / Q000032:analysis* / Q000302:isolation & purification*; D006046:Gold / Q000737:chemistry; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D009211:Myoglobin / Q000032:analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000032:analysis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D047392:beta-Cyclodextrins / Q000032:analysis
chemical_list: D001897:Boronic Acids; D002364:Caseins; D006023:Glycoproteins; D009211:Myoglobin; D047392:beta-Cyclodextrins; D012710:Serum Albumin, Bovine; D006046:Gold; D045304:Cytochromes c; C031215:betadex
keywords: Glycoprotein enrichment; Gold nanoparticle; Magnetic microbeads; Mass spectrometry; Signal amplification