Simultaneous quantification of total eicosapentaenoic acid, docosahexaenoic acid and arachidonic acid in plasma by high-performance liquid chromatography-tandem mass spectrometry.

A method for the simultaneous quantification of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and arachidonic acid (AA) in human plasma by HPLC-tandem mass spectrometry (HPLC-MS/MS) was developed and validated. Free and esterified forms of fatty acids were hydrolysed from plasma samples in the presence of an internal standard and subjected to liquid-liquid extraction. The chromatographic run time was 3.

Liquid chromatography-tandem mass spectrometry method for the simultaneous quantitative determination of the organophosphorus pesticides dimethoate, fenthion, diazinon and chlorpyrifos in human blood.

Simultaneous determination of the organophosphorus pesticides dimethoate, fenthion, diazinon and chlorpyrifos in human blood by HPLC-tandem mass spectrometry was developed and validated. The pesticides were extracted by a simple one-step protein precipitation procedure. Chromatography was performed on a Luna C(18) (30mmx2.

A high-performance liquid chromatography-mass spectrometry method using a novel atmospheric pressure chemical ionization approach for the rapid simultaneous measurement of tacrolimus and cyclosporin in whole blood.

Concentration monitoring and dose individualization is required to optimize either tacrolimus or cyclosporin therapy. In this study, the validation of a simple, rapid high-performance liquid chromatography-tandem mass spectrometry method for the simultaneous measurement of tacrolimus and cyclosporin in whole blood is reported. Blood samples (100 microL) were prepared by protein precipitation with zinc sulphate followed by acetonitrile (containing the internal standards ascomycin and cyclosporin D).

Cloned enzyme donor immunoassay tacrolimus assay compared with high-performance liquid chromatography-tandem mass spectrometry and microparticle enzyme immunoassay in liver and renal transplant recipients.

The immunosuppressant drug tacrolimus has a narrow therapeutic index and is subject to a large variation in individual bioavailability and clearance. With its narrow therapeutic index, therapeutic drug monitoring is standard clinical practice in the management of transplant recipients. In this study, we report the evaluation of the cloned enzyme donor immunoassay (CEDIA) for the determination of whole-blood tacrolimus concentrations compared with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and microparticle enzyme immunoassay (MEIA) using samples obtained from liver (n = 100) and renal (n = 88) transplant recipients.

FTY720, a synthetic sphingosine 1 phosphate analogue, inhibits development of atherosclerosis in low-density lipoprotein receptor-deficient mice.

Background: Numerous in vitro studies suggest that sphingosine 1-phosphate (S1P), a bioactive lysosphingolipid associated with high-density lipoproteins, accounts at least partly for the potent antiinflammatory properties of high-density lipoprotein and, thereby, contributes to the antiatherogenic potential attributed to high-density lipoproteins. The present study was undertaken to investigate whether modulation of S1P signaling would affect atherosclerosis in a murine model of disease.

Methods And Results: Low-density lipoprotein receptor-deficient mice on a cholesterol-rich diet were given FTY720, a synthetic S1P analogue, at low (0.

Measurement and stability of FTY720 in human whole blood by high-performance liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry.

We report here a validated method for the quantification of a new immunosuppressant drug FTY720, using HPLC-tandem mass spectrometry. Whole blood samples (500 microl) were subjected to liquid-liquid extraction, in the presence of an internal standard (Y-32919). Mass spectrometric detection was by selected reaction monitoring with an atmospheric pressure chemical ionization source in positive ionization mode (FTY720: m/z 308.

Evaluation of a fluorescent polarization immunoassay for whole blood everolimus determination using samples from renal transplant recipients.

Objectives: This study compared the performance of a fluorescent polarization immunoassay (FPIA) against HPLC-tandem mass spectrometry (HPLC-MS) for the measurement of everolimus in renal transplant recipients.

Design And Methods: A total of 333 pre-dose samples from 45 renal transplant patients were analyzed by FPIA and HPLC-MS.

Results: The inter-batch inaccuracy and precision of the FPIA for control samples were View Article and Find Full Text PDF

Comparison of the reintroduced MEIA assay with HPLC-MS/MS for the determination of whole-blood sirolimus from transplant recipients.

Therapeutic monitoring with dosage individualization of sirolimus drug therapy is standard clinical practice for organ transplant recipients. For several years sirolimus monitoring has been restricted as a result of lack of an immunoassay. The recent reintroduction of the microparticle enzyme immunoassay (MEIA) for sirolimus on the IMx analyser has the potential to address this situation.

CEDIA sirolimus assay compared with HPLC-MS/MS and HPLC-UV in transplant recipient specimens.

The role of the therapeutic drug monitoring laboratory in support of immunosuppressant drug therapy is well established, and the introduction of sirolimus (SRL) is a new direction in this field. The lack of an immunoassay for several years has restricted the availability of SRL assay services. The recent availability of a CEDIA SRL assay has the potential to improve this situation.

A rapid HPLC-mass spectrometry cyclosporin method suitable for current monitoring practices.

Objectives: Cyclosporin is an immunosuppressant drug with a narrow therapeutic window. Trough and 2-h post-dose blood samples are currently used for therapeutic drug monitoring in solid organ transplant recipients. The aim of the current study was to develop a rapid HPLC-tandem mass spectrometry (HPLC-MS) method for the measurement of cyclosporin in whole blood that was not only suitable for the clinical setting but also considered a reference method.

Quantification and stability of everolimus (SDZ RAD) in human blood by high-performance liquid chromatography-electrospray tandem mass spectrometry.

We report here a validated method for the quantification of a new immunosuppressant drug, everolimus (SDZ RAD), using HPLC-tandem mass spectrometry. Whole blood samples (500 microl) were prepared by protein precipitation, followed by C(18) solid-phase extraction. Mass spectrometric detection was by selected reaction monitoring with an electrospray interface operating in positive ionization mode.