A simple and easy-to-perform liquid chromatography–mass spectrometry method for the quantification of tacrolimus and its metabolites in human whole blood. Application to the determination of metabolic ratios in kidney transplant patients

Tacrolimus Monitoring in Liver Transplant Recipients, Posttransplant Cholestasis: A Comparative Between 2 Commercial Immunoassays and a Liquid Chromatography-Tandem Mass Spectrometry Method

“…However, the development of these methods is limited by the lack of commercially available pure standard solutions of metabolites. [27][28][29][30] Therefore, we did not measure metabolites in blood samples in our study. The metabolite concentrations are typically relatively low in blood samples from stable transplant recipients.…”

“…However, methods for quantifying TAC and its metabolites in human whole blood are useful tools for pharmacokinetic/ pharmacodynamic studies investigating the role of TAC metabolites. 27 Cholestasis results from disrupted bile flow from the liver to the intestinal tract, leading to the accumulation of various endogenous metabolites such as toxic bile acids. Therefore, an "unknown" endogenous compound associated with cholestasis may be the source of TAC overestimation by the QMS immunoassay.…”

A modified LC-MS/MS method for the detection of whole blood tacrolimus and its clinical value in Chinese kidney transplant patients

“…The mass spectrometer was coupled with paralleled HPLC systems, through which, not only a shorter analyzing time for each sample of 1.75 min was achieved, rejection of impurities that do not need to be tested could also avoid contamination of the mass spectrum. Although the total run time of each HPLC system was 3.5 min, it carried out a shorter analyzing time 1.75 min for each sample, which was more rapid than previous LC-MS/MS method [ 16 , 17 , 18 , 19 ]. It is indicated that the two simultaneously operating LC systems may be a feasible route to improve the throughput.…”

“…Simultaneously detect multiple immunosuppressants, regardless of whether clinical needed, may not be the best pathway for all labs to improve the assay throughput [ 13 , 14 , 15 ]. Third, because of the time-cost sample pretreatment and long separation time, insufficient throughput limits the clinical application of LC-MS/MS, especially for those with single liquid chromatography system and long run time [ 16 , 17 , 18 , 19 ].…”

Identification of Target Proteins Involved in Cochlear Hair Cell Progenitor Cytotoxicity following Gentamicin Exposure

“…This study also demonstrated the importance of mass spectrometry. MS is the current technology of choice for detecting and quantifying proteins and metabolites, as it is adaptable to virtually any type of sample, ranging from cells and neurons to subcellular organelles, tissues, and even whole embryos [ 58 , 59 , 60 , 61 , 62 , 63 , 64 ]. Mass spectrometers can directly detect intact proteins, peptides, post-translational modifications, and metabolites with high specificity, usually sub-mDa (sub-ppm) mass accuracy, and the capability for both discovery (untargeted) and targeted studies.…”