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In the present work, a fast, easy and efficient analytical method was developed and validated for the determination of phenolic compounds (4-hydroxybenzoic, vanillic, caffeic, p-coumaric, sinapic, ferulic and ellagic acids, and naringenin) in red sweet pepper. Extraction of phenolic compounds was carried out using the quick, easy, cheap, effective, rugged and safe (QuEChERS) method, followed by separation and detection using ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). When the acetate version of the QuEChERS method was used, higher amounts of the phenolic compounds were extracted. In the dispersive solid phase extraction (d-SPE) clean-up step, combination of 50 mg of octadecylsilane (C18) and 7.5 mg of graphitized carbon black (GCB), resulted in the greatest removal of interferents, especially carotenoids, without significant retention of phenolic compounds. The recoveries for the proposed method were 82-103%, the limits of quantification were 2-150 μg kg-1 , and the precision values expressed in terms of relative standard deviation (RSD) were ≤ 15%. The method developed was successfully applied to the analysis of different red sweet pepper cultivars.

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This study provides a fast, accurate and reproducible method for L-ascorbic acid (L-AA) determination in milk samples by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). A small volume of a low toxicity organic solvent (ethanol) was used for degreasing and deproteinization steps. Ethylenediaminetetraacetic acid disodium salt (EDTA) and formic acid were used as stabilizing agents. The method was successfully validated in terms of linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, and inter/intra-day precision and applied in raw and processed milk samples. Good linearity (r 2 > 0.9915) and low LOD and LOQ, 1.5 and 5.0 µg L-1 , respectively, were obtained. The recoveries for 500 and 1000 µg L-1 spikes were higher than 90% and the precision values expressed in terms of relative standard deviation (RSD) were ≤ 6.8%. For the first time, the determination of L-AA in a 500 µg L-1 concentration range was reported for milk samples.

To compare the pharmacokinetics of amoxicillin (AMX) in obese and nonobese subjects, given as single dose 875-mg tablets.Methods: A prospective, single-centre, open-label, clinical study was carried out involving 10 nonobese and 20 obese subjects given a dose of an AMX 875-mg tablet. Serial blood samples were collected between 0 and 8 hours after administration of AMX and plasma levels were quantified by liquid chromatography-tandem mass spectrometry. The pharmacokinetic parameters (PK) were calculated by noncompartmental analysis and means of the 2 groups were compared using Student t-test. Analysis of correlation between covariates and PK was performed using Pearson's correlation coefficient.Results: Ten nonobese subjects (mean age 30.6 ± 7.12 y; body mass index 21.56 ± 1.95 kg/m 2 ) and 20 obese subjects (mean age 34.47 ± 7.03 y; body mass index 33.17 ± 2.38 kg/m 2 ) participated in the study. Both maximum concentration (C max ; 12.12 ± 4.06 vs. 9.66 ± 2.93 mg/L) and area under the curve (AUC) 0-inf (34.18 ± 12.94 mg.h/L vs. 26.88 ± 9.24 mg.h/L) were slightly higher in nonobese than in obese subjects, respectively, but differences were not significant. The volume of distribution (V/F) parameter was statistically significantly higher in obese compared to nonobese patients (44.20 ± 17.85 L vs. 27.57 ± 12.96 L). Statistically significantThe authors confirm that the PI for this paper is Sérgio Seiji Yamada and that he had direct clinical responsibility for the patients.