Validation of an Enzyme-Linked Immunosorbent Assay Screening Method and a Liquid Chromatography-Tandem Mass Spectrometry Confirmation Method for the Identification and Quantification of Ketamine and Norketamine in Urine Samples from Malaysia

ABSTRACTMonitoring for chloramphenicol (CAP) in aquaculture products is primarily performed by liquid chromatography–tandem mass spectrometry (LC-MS/MS), which requires expensive equipment and specialized training. Many laboratories prefer to screen samples with facile and high-throughput enzyme-linked immunosorbent assay (ELISA) kits for CAP residues before submitting samples for LC-MS/MS quantification and confirmation. We evaluated the performance of a Ridascreen (R-Biopharm) ELISA kit for CAP in spiked and incurred crab and shrimp muscle at levels bracketing the minimum required performance level for analysis (0.3 ng/g). The Ridascreen ELISA kit incorporates antibody directed against CAP. Incurred CAP levels in crab and shrimp muscle were verified using LC-MS/MS. We found good repeatability (relative standard deviation) of the ELISA in spiked and incurred crab and shrimp muscle samples, with values ranging from 6.8 to 21.7%. Recoveries of CAP from tissues spiked at 0.15 to 0.60 ng/g ranged from 102 to 107%. Minimal cross-reactivity with blank crab and shrimp muscle matrix components was observed. ELISA data were highly correlated with those of LC-MS/MS for CAP in incurred muscle tissue. We believe this study to be the first evaluation of the performance and comparability of a CAP ELISA kit and LC-MS/MS for determination of CAP residues, as well as their elimination, in crab muscle. Our findings support the use of this ELISA kit for screening purposes and, when used in conjunction with validated instrumental methods, for regulatory monitoring of CAP in these species.

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Measurement of Circulating 25-Hydroxy Vitamin D Using Three Commercial Enzyme-Linked Immunosorbent Assay Kits with Comparison to Liquid Chromatography: Tandem Mass Spectrometry Method

ISRN Nutrition ◽

10.5402/2013/723139 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 16

Author(s):

Cheng-Shiun He ◽

Michael Gleeson ◽

William D. Fraser

Keyword(s):

Mass Spectrometry ◽

Vitamin D ◽

Liquid Chromatography ◽

Tandem Mass Spectrometry ◽

Immunosorbent Assay ◽

Enzyme Linked Immunosorbent Assay ◽

Tandem Mass ◽

Commercial Enzyme ◽

Chromatography Tandem Mass Spectrometry ◽

Liquid Chromatography Tandem Mass

Aim. The purpose of this study was to compare the accuracy and clinical implications of three commercial enzyme-linked immunosorbent assay (ELISA) kits (Eagle Biosciences, Immundiagnostik, and MicroVue) with a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the measurement of serum 25(OH)D concentration. Methods. Blood samples were obtained from 225 healthy individuals who were recruited as subjects from Loughborough University, UK. Plasma samples were measured for 25(OH)D concentration by means of LC-MS/MS and ELISA kits from Eagle Biosciences, Immundiagnostik, and MicroVue. Results. The 25(OH)D concentration measured by the Eagle Biosciences, Immundiagnostik, and MicroVue ELISAs biased −50.9 ± 79.1 nmol/L, −14.2 ± 91.0 nmol/L, and −7.2 ± 18.9 nmol/L (bias ± SD) from the LC-MS/MS method, respectively. We found that 52% (Eagle Biosciences), 48% (Immundiagnostik), and 38% (MicroVue) of participants were misclassified, and the results showed the poor agreement (Kappa: −0.201~0.251) in classification of participants defined as vitamin D sufficiency and insufficiency between each method and LC-MS/MS. Conclusions. The present study demonstrated that there were negative biases and considerable misclassification of participants using the cut-off point (50 nmol/L) for vitamin D insufficiency and sufficiency using the Eagle Biosciences, Immundiagnostik, and MicroVue ELISAs compared with the LC-MS/MS assay.

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An up-converting phosphor technology-based lateral flow assay for rapid detection of major mycotoxins in feed: Comparison with enzyme-linked immunosorbent assay and high-performance liquid chromatography-tandem mass spectrometry

PLoS ONE ◽

10.1371/journal.pone.0250250 ◽

2021 ◽

Vol 16 (4) ◽

pp. e0250250

Author(s):

Fenghua Zhu ◽

Beibei Zhang ◽

Lianqin Zhu

Keyword(s):

Mass Spectrometry ◽

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

Tandem Mass Spectrometry ◽

Immunosorbent Assay ◽

High Performance ◽

Enzyme Linked Immunosorbent Assay ◽

Tandem Mass ◽

Chromatography Tandem Mass Spectrometry ◽

Liquid Chromatography Tandem Mass

Current methods for detection of mycotoxin in feed are time-consuming and tedious. An up-converting phosphor technology-based lateral flow (UPT-LF) assay system is a new emerging technique for analytes detection. The aim of this study was to compare the performance of UPT-LF, an enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for detecting aflatoxin B1 (AFB1), zearalenone (ZEN) and deoxynivalenol (DON) in feed. The results showed that the use of UPT-LF for AFB1, ZEN and DON detection exhibited the following: limits of detection of 3, 50 and 200 μg/kg; average recoveries of 104.39%, 102.94% and 103.65%; and precision of 13.96%, 13.71% and 12.56%; respectively. UPT-LF required 45 min to determine one mycotoxin and 1.5 h to determine three mycotoxins in a sample, which took the shortest time. Besides, there were positive correlations between the UPT-LF, ELISA and HPLC/MS/MS methods. In conclusion, UPT-LF can be used to detect and quantify AFB1, ZEN and DON in feed samples. Though the sensitivity, accuracy and precision of UPT-LF are inferior to those of HPLC-MS/MS and ELISA, the UPT-LF assay is the most convenient and rapid technique for on-site detection among the three methods.

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