title: Surface Enhanced Laser Desorption Ionization of Phospholipids on Gold Nanoparticles for Mass Spectrometric Immunoassay.
abstract: High-throughput and sensitive detection of proteins are essential for clinical diagnostics and biomarker discovery. We develop a novel high-throughput, multiplexed, sensitive mass spectrometric (MS) immunoassay method, which utilizes antibody-modified phospholipid bilayer coated gold nanoparticles (PBL-AuNPs) as the detection label and antibody-immobilized magnetic beads as the capture reagent. This method enables magnetic enrichment of the PBL-AuNPs label specific to target protein, allowing sensitive surface enhanced laser desorption ionization (SELDI)-TOF MS detection of the protein via its specific label. AuNPs act as not only the support but also the matrix for the phospholipids in SELDI TOF MS detection. Moreover, with phospholipids with varying molecular weights as the encoded MS reporters, this method allows multiplexed detection of multiple proteins. With the use of a predefined phospholipids internal standard, this method also affords excellent reproducibility in protein quantification. We have demonstrated this method using the assays of two tumor biomarkers, and the results reveal that it provides a sensitive platform for multiplexed protein detection with detection limits in the picomolar ranges. This method may provide a useful platform for high-throughput and sensitive detection of protein biomarkers for clinical diagnostics.
authors.affiliation: State Key Laboratory of Chemeo/Bio-Sensing and Chemometrics, Institute of Chemical Biology and Nanomedicine, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Xiang-Cheng
authors.initials: XC
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Chemeo/Bio-Sensing and Chemometrics, Institute of Chemical Biology and Nanomedicine, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Xiang-Nan
authors.initials: XN
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Chemeo/Bio-Sensing and Chemometrics, Institute of Chemical Biology and Nanomedicine, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Lan
authors.initials: L
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Chemeo/Bio-Sensing and Chemometrics, Institute of Chemical Biology and Nanomedicine, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wen
authors.affiliation: State Key Laboratory of Chemeo/Bio-Sensing and Chemometrics, Institute of Chemical Biology and Nanomedicine, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Ru-Qin
authors.initials: RQ
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Chemeo/Bio-Sensing and Chemometrics, Institute of Chemical Biology and Nanomedicine, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Jian-Hui
authors.initials: JH
authors.lastname: Jiang