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This laboratory experiment employs an innovative approach to introduce undergraduates to liquid chromatography-tandem mass spectrometry (LC-MS/MS) by developing a method based on multiple reaction monitoring (MRM). During this qualitative investigation, students operated a triple quadrupole mass spectrometer in the MS scan and product ion scan modes to determine precursor and product ions, respectively, for a vanillin, ethyl vanillin, and coumarin standard mixture. After identifying precursor → product ion transitions, students conducted a 2 min liquid chromatography run in MRM mode. Students were astonished by the speed, selectivity, and sensitivity of the LC-MS/MS method compared to that of a liquid chromatograph with ultraviolet detection. [ABSTRACT FROM AUTHOR]

Laboratory experiments were developed to introduce students to the quantitation of drugs of abuse by high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). Undergraduate students were introduced to internal standard quantitation and the LC-MS/MS method optimization for cocaine. Cocaine extracted from paper currency was analyzed with a simple and rapid LC-MS/MS method. Students in advanced laboratories determined the amount of amphetamine, methamphetamine, and oxycodone on currency in addition to cocaine. The LC-MS/MS method has a short run time (2.5 min) to allow for a high throughput of student samples. [ABSTRACT FROM AUTHOR]

A five-week, research-based experiment suitable for second-semester introductory organic laboratory students is described. Each student designs, prepares, and analyzes a combinatorial array of six aromatic oligoamides. Molecules are prepared on solid phase via a six-step synthetic sequence, and purities and identities are determined by analysis of LC-MS data. This experiment engages students in a research experience: none of the structurally diverse compounds prepared have been previously reported in the literature. After completion of this experiment, products are evaluated for their biological activity in the author's research laboratory. Although execution of biological experiments falls outside the learning objectives in this course, these applications motivate students. Through these hands-on experiences, students learn about organic chemistry reactions and modern techniques, and their research skills are enhanced. [ABSTRACT FROM AUTHOR]

The article discusses the factors that contribute to variations in assays during quantitative analysis of sex steroid hormones when using liquid and gas chromatography coupled with mass spectrometry (LC-MS and GC-MS). Topics include the role of sex steroids in numerous physiological processes, factors to consider when trying to minimize assay variation, such as sample preparation, and steps for developing an effective assay for sex steroids.