scholarly journals Determination of Tranquilizers in Swine Urine by Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3215 ◽  
Author(s):  
Yingyu Wang ◽  
Xiaowei Li ◽  
Yuebin Ke ◽  
Chengfei Wang ◽  
Yuan Zhang ◽  
...  

A rapid, reliable, and sensitive method was developed for the determination of ten tranquilizers in swine urine. Sample preparation was based on solid-phase extraction, which combined isolation of the compounds and sample cleanup in a single step. Separation was performed on a reversed phase C18 column by gradient elution with a chromatographic run time of seven minutes, consisting of 0.1% formic acid in water and acetonitrile as the mobile phase. Multiple reaction monitoring in positive mode was applied for data acquisition. Matrix-matched calibration was used for quantification and good linearity was obtained with coefficients of determination higher than 0.99. The average recoveries of fortified samples at concentrations between 0.05 and 10 µg/L ranged from 85% to 106% with interday relative standard deviations of less than 13% in all cases. The limits of detection and limits of quantification obtained for tranquilizers in the urine were in the ranges of 0.03–0.1 µg/L and 0.05–0.25 µg/L, respectively. The applicability of the proposed method was demonstrated by analyzing real samples; diazepam was detected at concentrations between 0.3 and 0.6 μg/L.

2020 ◽  
Vol 58 (5) ◽  
pp. 769-779 ◽  
Author(s):  
Nele Peersman ◽  
Jan Van Elslande ◽  
Yannick Lepage ◽  
Samira De Amicis ◽  
Koenraad Desmet ◽  
...  

AbstractBackgroundOur goal was to develop a simple, rapid and precise ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for the determination of retinol and α-tocopherol in serum. Currently published LC-MS/MS methods either require complex extraction procedures (liquid-liquid or solid-phase) or do not meet desirable specifications for imprecision in serum (coefficient of variation [CV] <6.8% and 6.9%, respectively).MethodsSample preparation consisted of a simple protein precipitation with ethanol and acetonitrile. Stable isotope-labeled internal standards (IS) and a homemade calibration curve were used for quantification. The analysis was performed using an Acquity I-class Xevo TQ XS LC-MS/MS. Chromatographic runtime was 6.0 min using a reversed phase gradient elution. UniSpray (US) as an ionization technique was compared to electrospray ionization (ESI). Analytical validation included matrix effect, recovery and trueness compared to National Institute of Standards and Technology (NIST) standards and United Kingdom National External Quality Assessment Service (UK NEQAS) samples.ResultsIntra- and inter-run CVs were <4.9% for retinol and <1.7% for α-tocopherol, both complying with desirable specifications for imprecision. Bias compared to NIST standards was <3.1% for both compounds. The method was linear over the entire tested range. The lower limit of quantification (LLOQ) with US was lower than with ESI for both retinol (0.022 vs. 0.043 mg/L) and α-tocopherol (0.22 vs. 0.87 mg/L). Matrix effects were not significant (<15%) for retinol. However, for α-tocopherol matrix effects of on average 54.0% were noted using ESI, but not with US.ConclusionsWe developed a fast, precise and accurate UPLC-MS/MS method for the determination of retinol and α-tocopherol in human serum using a single-step sample pretreatment. Ionization using US eliminated the matrix effects for α-tocopherol.


2014 ◽  
Vol 7 (2) ◽  
pp. 121-129 ◽  
Author(s):  
L. Luan ◽  
N. Chen ◽  
Z. Han ◽  
X. Liu ◽  
Y. Zheng ◽  
...  

A reliable ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous determination of aflatoxin B1, aflatoxin B2, mycophenolic acid and sterigmatocystin in grape pomace. The samples were extracted by acetonitrile aqueous solution and further purified using a solid-phase extraction-based homemade clean-up cartridge. Next, the analytes were separated on a reversed-phase C18 column with a mobile phase consisting of water and acetonitrile. The separated compounds were detected with a tandem quadrupole mass spectrometer operating in positive electro-spray ionisation mode using multiple reaction monitoring. The established method was extensively validated by determining linearity (R2≯0.999), recovery (97.5-102.8%) and precision (relative standard deviation ≤7.0%). This method was then used for the simultaneous determination of the four mycotoxins in grape pomace samples.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Qiang Wang ◽  
Xu-Feng Wang ◽  
Yong-Yuan Jiang ◽  
Zhi-Guang Li ◽  
Nan Cai ◽  
...  

AbstractWe developed a significantly improved ultra-high performance liquid chromatography-tandem mass spectrometry method for determination of 5-nitro-2-furaldehyde (NF) as a surrogate using a novel internal standard for the detection of nitrofurazone. We used 2,4-dinitrophenylhydrazine derivatization and furfural as the internal standard. Derivatization was easily performed in HCl using ultrasonic manipulation for 5 min followed by liquid extraction using ethyl acetate. The samples were concentrated and purified using reverse phase and alumina cartridges in tandem. The derivatives were separated using a linear gradient elution on a C18 column with methanol and water as the mobile phase in negative ionization mode and multiple reaction monitoring. Under the optimized conditions, the calibration curves were linear from 0.2 to 20 μg/L with correlation coefficients >0.999. Mean recoveries were 80.8 to 104.4% with the intra- and inter-day relative standard deviations <15% at spiking levels of 0.1 to 10 μg/kg. The limits of detection and quantification were 0.05 and 0.1 μg/kg, respectively. This method is a robust tool for the identification and quantitative determination of NF in shrimp samples.


2017 ◽  
Vol 12 (12) ◽  
pp. 1934578X1701201
Author(s):  
Bernadette Messi Biloa ◽  
Raimana Ho ◽  
Guillaume Marti ◽  
Alain Meli Lannang ◽  
Jean-Luc Wolfender ◽  
...  

Following investigation of Garcinia genus, a sensitive, rapid and simple reversed-phase high performance liquid chromatography-electrospray ionization mass spectrometry method has been developed for the identification and quantification of three polyisoprenylated benzophenones, garcinol (1), isogarcinol (2) and 7- epi-clusianone (3), in the extracts of five Garcinia species from Cameroon. The separation of those compounds was achieved on a RP-18 column using a solvent system consisting of a mixture of acetonitrile-water-formic acid as a mobile phase in a gradient elution mode. The identification of the three compounds was determined on a triple quadripole mass spectrometer with ESI interface operating in the negative mode. A multiple reaction monitoring (MRM) method was developed for the quantification of these polyisoprenylated benzophenones in the extracts of the Garcinia species. The method was validated through intra- and inter-day precision, with the relative standard deviation (RSD) less than 6%, limits of detection (LOD) and limits of quantification (LOQ) <1 ng. Overall recoveries ranged from 94% to 104%, with RSDs ranging from 0.8% to 4.5%. The results indicated that the fruits of G. preussii and the roots of G. brevipedicellata are good source of garcinol (1) and isogarcinol (2) respectively.


Author(s):  
Francesca Merlo ◽  
Federica Maraschi ◽  
Davide Piparo ◽  
Antonella Profumo ◽  
Andrea Speltini

The purpose of this study was to set up a sensitive method for the simultaneous determination of phycotoxins and cyanotoxins—Emerging pollutants with different structures and harmful properties (hepatotoxicity, neurotoxicity and cytotoxicity)—In environmental waters. Due to the low concentrations detected in these samples, a pre-concentration step is required and here it was performed in a single step with a commercial cartridge (Strata™-X), achieving enrichment factors up to 200 and satisfactory recovery (R = 70–118%) in different aqueous matrices. After solid-phase extraction (SPE), toxins were separated and quantified by High Performance Liquid Chromatography- Heated ElectroSpray Ionisation Tandem Mass Spectrometry (HPLC-HESI-MS/MS) in Multiple Reaction Monitoring (MRM) mode. An analytical evaluation of the proposed method was done based on the analytical figures of merit, such as precision and trueness, linearity, selectivity, and sensitivity, and it turned out to be a robust tool for the quantification of ng L−1 levels, phycotoxins and cyanotoxins in both freshwater and saltwater samples.


Author(s):  
Ashok K Singh ◽  
Vinit Raj ◽  
Amit Rai ◽  
Amit K Keshari ◽  
Pranesh Kumar ◽  
...  

Objective: Recently, we reported newly synthesized 5H-benzo[2,3][1,4]oxazepino[5,6-b]indole) derivatives and proved their cytotoxicity against hepatocellular carcinoma specific Hep-G2 cell lines. We attempted herein to describe a reversed-phase high-performance liquid chromatographic method for the determination of three most active compounds 6a, 10a, and 15a in rat plasma to predict their pharmacokinetics parameters before in vivo study.Methods: A rapid and sensitive reversed-phase high-performance liquid chromatographic was employed for the determination of 6a, 10a, and 15a in rat plasma. Each compound was separated by a gradient elution of acetonitrile and water with 1 mL/min flow rate. The detector was set at 270, 285, and 275 nm for 6a, 10a, and 15a and the recorded elution times were 2.00, 2.87, and 1.88 min, respectively.Results: The calibration curve was linear with R2 of 0.938, 0.875, and 0.923 over the concentration range of 0.1–50 μg/mL. The inter- and intra-day variations of the assay were lower than 12.26%; the average recovery of 6a, 10a, and 15a was 97.31, 92.56, and 95.23 % with relative standard deviation of 2.12%, 3.25%, and 2.28%, respectively. The Cmax and Tmax were ~ 46.34, 18.56, and 25.65 μg/mL and 2.0, 4.0, and 4.0 h for 6a, 10a, and 15a, respectively, which indicate a robust method of detection in the present experiment.Conclusion: The study suggests that all of the three compounds have a lower rate of absorption, higher volume of distribution, and lower clearance rate, indicating good therapeutic response for in vivo activity. 


2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Abderrezak Khelfi ◽  
Mohammed Azzouz ◽  
Rania Abtroun ◽  
Mohammed Reggabi ◽  
Berkahoum Alamir

Background and Objective. In this study, turbo-ion spray as an interface of tandem mass spectrometry (MS/MS) was performed for sensitive and accurate quantification of chlorpromazine, haloperidol, levomepromazine, olanzapine, risperidone, and sulpiride in plasma samples. Methods. Separation was performed by gradient reversed phase high-performance liquid chromatography using a mobile phase containing ammonium formiate 2 mM, pH 2.7, and acetonitrile flowing through a Restek PFP Propyl C18 analytical column (50 mm×2.1 mm i.d.) with particle size of 5 µm, at a flow rate of 800 µL/min. Positive ion fragments were detected in multiple reaction monitoring (MRM) mode. Sample preparation was achieved by solid phase extraction (SPE) (Oasis HLB). Results. Mean extraction recoveries ranged from 82.75% to 100.96%. The standard calibration curves showed an excellent linearity, covering subtherapeutic, therapeutic, and toxic ranges. Intraday and interday validation using quality control (QC) samples were performed. The inaccuracy and imprecision were below 12% at all concentration levels. The limits of detection (LOD) and quantification (LOQ) for all analytes were under therapeutic ranges for all tested analytes. Thus, the proposed method was sensitive enough for the detection and determination of subtherapeutic levels of these antipsychotics in plasma samples. No interference of endogenous or exogenous molecules was observed and no carryover effects were recorded. Conclusion. According to the results, the proposed method is simple, specific, linear, accurate, and precise and can be applied for antipsychotic analysis in clinical routine. This method was applied for the determination of the tested antipsychotics in plasma samples taken from 71 individuals.


1999 ◽  
Vol 82 (1) ◽  
pp. 213-216 ◽  
Author(s):  
Nicholas G Tsiropoulos ◽  
Pipina G Aplada-Sarlis ◽  
George E Miliadis

Abstract A liquid chromatographic (LC) method was developed and statistically validated for simultaneous determination of 5 benzoylurea insecticides (di-flubenzuron, triflumuron, teflubenzuron, flufenoxuron, and lufenuron) in apples and pears. It involves preliminary extraction with ethyl acetate–sodium sulfate and cleanup on silica solid-phase extraction cartridges using dichloromethane–2-propanol (9 + 1) as eluant. The eluate is dried under nitrogen and redissolved in methanol. Benzoylurea insecticides are determined by reversed-phase LC with gradient elution at 42°C and UV diode array detection. Recoveries from samples fortified with the 5 insecticides at 0.02–0.5 mg/kg ranged from 83 to 102% for apples and from 75 to 99% for pears. Relative standard deviations were 0–12%. Limits of detection were 0.01 mg/kg for apples and 0.02 mg/kg for pears.


2006 ◽  
Vol 89 (2) ◽  
pp. 352-358 ◽  
Author(s):  
Jan Krzek ◽  
Jolanta Kaleta ◽  
Urszula Hubicka ◽  
Aneta Niedzwiedz

Abstract A reversed-phase high-performance liquid chromatography method with gradient elution was developed for the determination of the caffeic, p-coumaric, and ferulic acids in propolis concentrates. Solid-phase extraction on an RP18 column was applied for preliminary purification, and chromatographic separation was performed on 100 RP18e Lichrospher column of particle size 5 m. The mobile phase was obtained by mixing in appropriate ratios 0.03 mM NaH2PO4, acidified with H3PO4 up to pH 3.0, with acetonitrile to obtain a gradient in the elution process. Spectrophotometric detection was conducted at 320 nm. Under the established conditions, the method featured high sensitivity, good precision, and comparability of results, as proven by method validation and statistical analysis of the obtained results. The limits of detection were 0.315, 0.325, and 0.695 g/mL for caffeic, p-coumaric, and ferulic acids, respectively. The corresponding recovery values were 98.14, 101.05, and 99.42 and the linearity ranges from 1.31 to 99.18 g/mL, 1.52 to 119.16 g/mL, and 2.42 to 184.14 g/mL. The precision of the method was expresed by relative standard deviation values that did not exceed 3. It was also shown that the propolis concentrates under examination had similar antibacterial activity against Staphylococcus aureus ranging from 119.8 to 124.3 g/mL, contrary to model mixtures that showed no antibacterial activity.


2005 ◽  
Vol 88 (6) ◽  
pp. 1688-1694 ◽  
Author(s):  
Guixiang Yang ◽  
Baoyin Lin ◽  
Zhenling Zeng ◽  
Zhangliu Chen ◽  
Xianhui Huang

Abstract A liquid chromatographic method with fluorescence detection was developed for simultaneous determination of norfloxacin, ofloxacin, ciprofloxacin, pefloxacin, lomefloxacin, danofloxacin, enrofloxacin, sarafloxacin, difloxacin, oxolinic acid, and flumequine in milk. The samples were extracted with 10% trichloroacetic acid/acetonitrile (9 + 1, v/v) and cleaned by Strata-X reversed-phase solid-phase extraction cartridges. The 11 quinolones were separated on a reversed-phase C18 column (Hypersil BDS-C18) with mobile phase gradient elution and detected with fluorescence by means of a wavelength program. The recoveries for milk fortified with the 11 quinolones at 3 levels were 69–88%, with acceptable relative standard deviations of &lt;9% (intraday) and &lt;14% (interday). The limits of detection were 23 μg/L for enrofloxacin, and 1–9 μg/L for the other 10 quinolones.


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