High‐throughput LC–MS/MS method with 96‐well plate precipitation for the determination of arotinolol and amlodipine in a small volume of rat plasma: Application to a pharmacokinetic interaction study

Abstract

A rapid, sensitive, and selective liquid chromatography with tandem mass spectrometry method was developed and fully validated for the simultaneous quantification of arotinolol and amlodipine in rat plasma. Two internal standards were introduced with metoprolol as the internal standard of arotinolol and (S)-amlodipine-d4 as the internal standard of amlodipine. The analytes were isolated from 50.0 μL plasma samples by a simple protein precipitation using acetonitrile. The chromatographic separation was achieved in 5 min on a C18 column. The mobile phase consisted of phase A 5% methanol and phase B 95% methanol (both containing 0.5% formic acid and 5 mM ammonium acetate) and was delivered in gradient elution at 0.300 mL/min. Quantification was performed in multiple reaction monitoring mode with the transition m/z 372.1 → 316.1 for arotinolol, m/z 268.2 → 116.2 for metoprolol, m/z 409.1 → 238.1 for amlodipine and m/z 413.1 → 238.1 for (S)-amlodipine-d4. Linearity was obtained over the range of 0.200-40.0 ng/mL for arotinolol (r = 0.9988) and 0.500-100 ng/mL for amlodipine (r = 0.9985) in rat plasma. The validated data have met the acceptance criteria in FDA guideline. This method was successfully applied to a pharmacokinetic interaction study in rats, and the results indicated that there was no significant drug-drug interaction between arotinolol and amlodipine.

High‐throughput quantification of drugs of abuse in biofluids via 96‐solid‐phase microextraction–transmission mode and direct analysis in real time mass spectrometry

“…In paper spray, drying time (minutes, in some cases hours) and spraying times (seconds to minutes) tend to vary with applications, but total analysis times usually are not excessively long. When compared with hyphenated techniques like LC/MS (where processing can take hours), analysis time is significantly reduced with the 96‐SPME‐TM. Techniques like RapidFire (RF) report analysis time of 45 min for 384 wells, or 7 s per sample, but it is important to keep in mind that, unlike SPME, RF requires plasma pre‐processing .…”

“…Although the majority of reports indicate an expected drop in plasma protein binding when a dilution is utilized, 63 this study was not concerned with determining the % of plasma protein binding. 69,70 (where processing can take hours), analysis time is significantly reduced with the 96-SPME-TM. Techniques like RapidFire (RF) report analysis time of 45 min for 384 wells, or 7 s per sample, 71 but it is important to keep in mind that, unlike SPME, RF requires plasma pre-processing.…”

Recent advances in the bioanalytical methods of polyethylene glycols and PEGylated pharmaceuticals

“…Multiple reaction monitoring (MRM) based on LC–MS/MS (LC–MRM) is a “gold standard” for the bioanalysis of small molecules [168–181]. MRM assay is a target MS technique based on ESI–MS [182–191]. The operating principle composes following stages: in the first quadrupole (Q1), an analyte ion with certain mass will be selected; the selected ions will be consequently fragmentized by collision‐induced dissociation (CID); a single or multiple specific fragment ions are selected again by the second quadrupole (Q2) and transmitted into the third quadrupole (Q3) for detection (Figure 5I) [192–197].…”

A Sensitive Spectrofluorimetric Method for Curcumin Analysis

“…96-well plates can be easily accommodated in all common instruments like HPLC, GC, LC-MS and can be used for applications such as sample collection and biological assays. [ 37 , 38 ] The advantages of 96-well plates are that sample processing is easy, requires fewer reagents as the well volume is small and requires fewer plates to run an experiment because more samples can be placed within the plate when compared over conventional sample holders. [ 39 ].…”