title: Quantification of captopril in urine through surface-assisted laser desorption/ionization mass spectrometry using 4-mercaptobenzoic acid-capped gold nanoparticles as an internal standard.
abstract: We have developed a new internal standard method for the determination of the concentration of captopril (CAP) through surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) using gold nanoparticles (Au NPs). This approach provided linearity for CAP over the concentration range 2.5-25 microM (R(2) = 0.987), with a limit of detection (signal-to-noise ratio = 3) of 1.0 microM. The spot-to-spot variations in the concentration of CAP through SALDI-MS analyses performed in the absence and presence of the internal standard were 26% and 9%, respectively (15 measurements). This approach provides simplicity, accuracy, precision, and great reproducibility to the determination of the levels of CAP in human urine samples.
authors.affiliation: Department of Chemistry, National Taiwan University, Taipei, Taiwan.
authors.forename: Wen-Tsen
authors.initials: WT
authors.lastname: Chen
authors.forename: Cheng-Kang
authors.initials: CK
authors.lastname: Chiang
authors.forename: Yang-Wei
authors.initials: YW
authors.lastname: Lin
authors.forename: Huan-Tsung
authors.initials: HT
authors.lastname: Chang
mesh_terms: D001565:Benzoates / Q000737:chemistry*; D002216:Captopril / Q000652:urine*; D006046:Gold / Q000737:chemistry*; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D001565:Benzoates; D013438:Sulfhydryl Compounds; C013594:4-mercaptobenzoate; D006046:Gold; D002216:Captopril