Department of Chemistry, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan.
Rapid Commun Mass Spectrom. 2011 Jan 30;25(2):307-15. doi: 10.1002/rcm.4843.
Single drop microextraction (SDME) coupled with matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been applied for direct analysis of hydrophobic peptides (valinomycin and gramicidin D) from biological samples (urine and plasma) in high salt solution. The optimal conditions such as selection of extraction solvent, stirring rate, extraction time, effect of salt concentration and matrix-to-analyte ratio were investigated. The limits of detection (LODs) were found to be 73 nM to 170 nM for valinomycin and 96 nM to 5.5 µM for gramicidin D in high salt solution (1.7 M of NaCl) in MALDI-MS. The current approach can enhance the LODs by 11-320-fold for gramicidin D analysis in water, urine and plasma in high salt solution. Furthermore, the current approach has been successfully demonstrated for real-world sample analysis (β-carotene from carrots) by MALDI-MS. The current approach is a rapid, simple and efficient clean-up platform for direct analysis of hydrophobic molecules in biological samples from high salt solution.
单滴微萃取 (SDME) 与基质辅助激光解吸/电离质谱 (MALDI-MS) 联用，已被应用于从高盐溶液中的生物样品（尿液和血浆）中直接分析疏水性肽（缬氨霉素和短杆菌肽 D）。考察了萃取溶剂的选择、搅拌速度、萃取时间、盐浓度和基质与分析物比例的影响等最佳条件。在 MALDI-MS 中，对于高盐溶液（1.7 M NaCl）中的缬氨霉素，LOD 为 73 nM 至 170 nM，对于短杆菌肽 D，LOD 为 96 nM 至 5.5 µM。该方法可将水、尿液和高盐溶液中的血浆中短杆菌肽 D 的分析灵敏度提高 11-320 倍。此外，该方法还成功地通过 MALDI-MS 对实际样品（胡萝卜中的β-胡萝卜素）进行了分析。该方法是一种快速、简单、高效的净化平台，用于直接分析高盐溶液中生物样品中的疏水分子。
