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control the cardiovascular complications. Hence, it was thought worthwhile to develop an ultra-performance liquid chromatography (UPLC) and high-resolution mass spectrometry (HR-MS) method which can simultaneously separate, quantify, and characterize the

Open access

Triclocarban (TCC) and triclosan (TCS) are used in a wide range of household and personal care products and have been the most frequently detected organic pollutants in both wastewater and surface water. This paper presented a rapid analytical method for simultaneous determination of TCC and TCS in wastewater. The method involves the extraction and cleanup of the target compounds by using silicon dioxide/polystyrene composite microspheres solid-phase extraction and detection with ultra-high-pressure liquid chromatography. Under the optimized conditions, the limits of detection were 0.028 μg/L and 0.040 μg/L for TCC and TCS, respectively. Under the concentrations of the spiking level ranging from 0.100 μg/L to 2.000 μg/L, the spiked recoveries of TCC and TCS in wastewater samples achieved in the range of 89.5–102.8% with RSD below 6.3% for TCC and 95.5–103.6% with RSD below 6.9% for TCS. This method was successfully used in monitoring the water samples from three traditional wastewater treatment plants.

Open access
Acta Chromatographica
Authors:
Lianguo Chen
,
Qingwei Zhang
,
Yijing Lin
,
Xiaojie Lu
,
Zuoquan Zhong
,
Jianshe Ma
,
Congcong Wen
, and
Cheng Ding

spectrometry (UPLC–MS/MS) method was established to determine hapepunine in mouse blood, the pharmacokinetics of hapepunine after intravenous and intragastric administration was studied, and the absolute bioavailability was obtained

Open access

. Therefore, monitoring the plasma concentrations of nobiletin and tangeretin is of great significance for the clinical and food application of C. aurantium L . The detection sensitivity of HPLC method is low, while UPLC-MS/MS has low detection limit [ 10

Open access

increase the autophagy level [ 15 ]. However, the study on the pharmacokinetics of pancratistatin in vivo has not been reported. Therefore, it is necessary to clarify the pharmacokinetics in vivo . In this work, a rapid and selective UPLC-MS/MS method

Open access

], and their pharmacokinetics assessed after oral or intravenous (iv) intake. However, HPLC sensitivity is low, whereas ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) technology exhibits high sensitivity, low detection

Open access
Acta Chromatographica
Authors:
Xiuhui Tian
,
Dianfeng Han
,
Yanmei Cui
,
Lihua Ren
,
Fang Jiang
,
Hui Huang
,
Xianghong Gong
,
Jinglin Xue
,
Jiawei Li
,
Huihui Liu
,
Yingjiang Xu
,
Xiaojun Luo
,
Xiaojing Liu
, and
Xiuzhen Zhang

Abstract

A sensitive and validated method for determining quinocetone and its main metabolites (3-methylquinoxaline-2-carboxylic acid and dedioxoquinenone) was established in aquatic products using ultra-high-performance liquid chromatography-tandem spectrometry (UHPLC-MS/MS). Samples were extracted with 2.0 mol L−1 hydrochloric acid, then purified on MAX columns. After extraction and purification, the supernatant was evaporated to dry nearly under a gentle stream of nitrogen at 40 °C. Formic acid-acetonitrile-water (0.1/30/70, v/v/v) was adjusted to 1.00 mL final volume. An aliquot (10 μL) was injected into the C18 column for separation with the mobile phase of acetonitrile and 0.5% formic acid in water at 0.25 mL min−1. Calibration curves were linear ranged from 10.00 ng mL−1 to 200.0 ng mL−1 for quinocetone and 3-methylquinoxaline-2-carboxylic acid, and 20.00 ng mL−1 to 400.0 ng mL−1 for dedioxoquinenone. Mean recoveries were 70%–89%, 73%–83% and 72%–84%, respectively. The limit of detection (LOD) was 1.00 μg kg−1, 1.00 μg kg−1 and 2.00 μg kg−1, and quantification (LOQ) were 2.00 μg kg−1, 2.00 μg kg−1 and 4.00 μg kg−1 for quinocetone, 3-methylquinoxaline-2-carboxylic acid, and dedioxoquinenone. Based on the method above, the analytes were determined in Apostichopus japonicus, three fishes (including Ctenopharyngodon idellus, Crucian carp and Oreochromis mossambicus), Penaeus vannamei, Penaeus chinensis, and Chlamys farreri. The method shows good sensitivity, linearity, precision, and accuracy. In short, the proposed method was reliable for the determination of quinocetone, 3-methylquinoxaline-2-carboxylic acid, and dedioxoquinenone in aquatic products.

Open access

reports about the pharmacokinetics of eugenitin in biological fluids. Therefore, it was necessary to develop a UPLC-MS/MS method for the pharmacokinetics. In this study, UPLC-MS/MS was used to detect eugentin in mouse blood and its pharmacokinetics was

Open access
Acta Chromatographica
Authors:
Ruijie Chen
,
Mengrou Lu
,
Xiaoting Tu
,
Wei Sun
,
Weijian Ye
,
Jianshe Ma
,
Congcong Wen
,
Xianqin Wang
, and
Peiwu Geng

]. There is no effective bioanalytical method available to quantify panasenoside in biological samples to date. Compared to liquid chromatography tandem mass spectrometry (LC–MS/MS), ultra-performance liquid chromatography (UPLC)–MS/MS is more sensitive and

Open access

models, determined using LC–ion trap MS, has not yet been reported. Therefore, in the present study, a simple, rapid, and selective UPLC–ion trap MS method for the quantification of atractylenolide III in the rat plasma samples after oral

Open access