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A rapid and sensitive ultra-HPLC/MSIMS (UHPLC/MSIMS) assay method for the simultaneous determination in human urine of 22 drugs belonging to different pharmaceutical groups was developed. The drugs were extracted from urine samples and then separated on a Zorbax Rapid Resolution High Definition SB-C18 column. The mobile phase consisted of methanol and water containing formic acid with gradient elution. The chromatographic separation time was 7 min. The MSIMS detector, equipped with an electrospray ionization source, was set up in both positive and negative modes. The lower LOQs for the drugs in this method were between 0.05 and 0.60 ng/mL. Calibration curves in human urine were generated in the range of 0.05-600 ng/mL. Method validation parameters such as intraday and interday precision, accuracy, extraction recovery, stability, selectivity, dilution integrity, and carryover effect for all the compounds were within the acceptable ranges. This simple and fast method was applied successfully to study the pharmacokinetics of four selected drugs in human urine collected from patients. This UHPLC/MS/MS method offers an attractive way forward for the development of a routine rapid analysis for selected substances, particularly given the growing amount of new information about drug properties.

A simple method using solid-phase extraction (SPE) and ultra high-performance liquid chromatography (UHPLC) for the simultaneous determination of β-blockers, isoflavones, and flavonoids in human urine is developed. A statistical central composite design and response surface analysis is used to optimize the separation of the analytes. These multivariate procedures are efficient in determining the optimal separation condition using resolutions and retention time as responses. A gradient elution using a mobile phase consisting of 0.05% trifluoroacetic acid in water and acetonitrile is applied on a Hypersil GOLD column within a short analysis time of 4.5 min. UV detection was used to monitor the analytes. The suggested method was linear in a concentration range from 0.04-20.00 μg/mL, depending on the compound. The limits of detection ranged from 8.9 to 66.2 ng/mL. The precision was lower than 2.74%, and the accuracy was between 0.01-3.65%. The Oasis HLB column, with the highest recoveries, is selected for the pre-concentration step. This present paper reports, for the first time, a method for the simultaneous determination of β-blockers, isoflavones, and flavonoids in human urine samples. Furthermore, the developed method can also be applied to the routine determination of examined compounds concentrations in human urine.

A simple and fast ultra-high-performance liquid chromatography (UHPLC) method was developed for the identification and quantification of the following flavonoids in red wine: (+/-)-catechin, (-)-epicatechin, rutin, quercitrin, hesperidin, neohesperidin, (+/-)-naringenin, hesperetin, and chrysin. Chromatographic separation of the flavonoids was performed on a Chromolith Fast Gradient C18e column. A gradient elution was used with mobile phases consisting of 0.1% formic acid in water and acetonitrile. UV detection was performed at 280 nm. A complete separation of flavonoids was possible within 6 min. The calibration curves showed good linearity (R2 > or = 0.9990) in the selected range of each analyte; the LOD ranged between 0.06 and 0.19 microg/mL. An optimized sample preparation method utilized SPE. The Oasis HLB column with the highest recoveries was selected for the preconcentration step. This method was successfully applied to the determination of these flavonoids in the red wine samples with excellent results.