Sample preparation frequently is considered the most critical stage of the analytical workflow. It affects the analytical throughput and costs; moreover, it is the primary source of error and possible sample contamination. To increase efficiency, productivity, and reliability, while minimizing costs and environmental impacts, miniaturization and automation of sample preparation are necessary.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
August 2021
An on-line solid phase extraction using a lab-made restricted access media (RAM) was developed as sample preparation procedure for determination of the pharmaceutical compounds caffeine (CAF), carbamazepine (CBZ), norfloxacin (NOR), ciprofloxacin (CIP), fluoxetine (FLX) and venlafaxine in wastewater treatment plant samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS). This method is suitable for use in routine of analysis, avoiding cross-contamination and requiring only a small sample volume (50 µL), with minimal handling. The method was validated according to international guidelines.
View Article and Find Full Text PDFAn original, selective and automated method, for the microextraction by packed sorbent (MEPS) of Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-tetrahydrocannabinol (THC-OH), and 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) from human urine, was developed by using (i) a catechin-molded molecularly imprinted polymer (MIP), (ii) a new lab-made MEPS device easily repackable with any commercial or lab-made sorbent, and (iii) a lab-made multi syringe autosampler. Analyses were performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and the developed method proved to be precise, accurate and showed good linearity. Determination coefficients ranged from 0.
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