title: Designer SiO₂@Au nanoshells towards sensitive and selective detection of small molecules in laser desorption ionization mass spectrometry.
abstract: We report a novel platform using optimized SiO2@Au core-shell structures as matrices for highly efficient laser desorption/ionization mass spectrometry analysis of small biomolecules (MW<700 Da). Owing to the designer structure, SiO2@Au nanoshells can achieve low detection-of-limits (~pmol-fmol) in mass spectrometry and selective laser desorption/ionization in bio-mixtures towards diverse small molecules. By further surface modification with aptamers, Apt-SiO2@Au nanoshells allowed simultaneously targeted enrichment and detection of kanamycin with a detection limit at 200 pM. Our work not only starts new applications of SiO2@Au nanoshells in mass spectrometry, but also contributes to advanced analysis of either a group of small molecules or one target small molecule from complex bio-samples in a pre-designed manner for bio-diagnostics.
  
  
  BACKGROUND
  Existing methods for the detection of small molecules are often not sensitive enough. Here, the authors developed aptamer functionalized SiO2@Au nanoshells for use in mass spectrometry, with very low detection limits. The new platform appeared to be simple and efficient and should be applicable in detection of clinical samples.
authors.affiliation: Department of Chemistry, Institute of Biomedical Sciences and State Key Lab of Molecular Engineering of Polymers, Fudan University, Shanghai, China.
authors.forename: Jinrui
authors.initials: J
authors.lastname: Gan
authors.affiliation: Center for Bio-Nano-Chips and Diagnostics in Translational Medicine (CBD™), School of Biomedical Engineering and Med-X Research Institute, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Wei
authors.affiliation: Department of Chemistry, Institute of Biomedical Sciences and State Key Lab of Molecular Engineering of Polymers, Fudan University, Shanghai, China.
authors.forename: Yixin
authors.initials: Y
authors.lastname: Li
authors.affiliation: Center for Bio-Nano-Chips and Diagnostics in Translational Medicine (CBD™), School of Biomedical Engineering and Med-X Research Institute, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Jiao
authors.initials: J
authors.lastname: Wu
authors.affiliation: Center for Bio-Nano-Chips and Diagnostics in Translational Medicine (CBD™), School of Biomedical Engineering and Med-X Research Institute, Shanghai Jiao Tong University, Shanghai, China. Electronic address: k.qian@sjtu.edu.cn.
authors.forename: Kun
authors.initials: K
authors.lastname: Qian
authors.affiliation: Department of Chemistry, Institute of Biomedical Sciences and State Key Lab of Molecular Engineering of Polymers, Fudan University, Shanghai, China. Electronic address: bhliu@fudan.edu.cn.
authors.forename: Baohong
authors.initials: B
authors.lastname: Liu
mesh_terms: D006046:Gold / Q000737:chemistry; D057230:Limit of Detection; D057145:Nanoshells / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D054852:Small Molecule Libraries / Q000737:chemistry / Q000302:isolation & purification*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D054852:Small Molecule Libraries; D006046:Gold; D012822:Silicon Dioxide
keywords: Laser desorption/ionization; Mass spectrometry; Silica-gold nanoshells; Small molecules; Surface chemistry