Effect of various anticoagulants on the bioanalysis of drugs in rat blood: implication for pharmacokinetic studies of anticancer drugs.

Preeti Kulkarni,Murari Gurjar,Bhaskar H Vidhun,Vikram Gota,Sagar Dhoble,Arvind B Naik,Ashwin Karanam

doi:10.1186/s40064-016-3770-4

Preeti Kulkarni, Murari Gurjar + Show 5 more

Open Access

https://doi.org/10.1186/s40064-016-3770-4

Copy DOI

Abstract

BackgroundPharmacokinetic studies are vital in development and optimization of drugs. While blood samples can be collected either in EDTA, heparin or citrate containing tubes for the estimation of drug levels in plasma, EDTA tubes are more commonly used. The purpose of this study was to evaluate the effects of anticoagulants on bioanalysis of drugs. Six drugs used extensively in cancer therapy were selected. Albino wistar rats (N = 6 per drug) were dosed with one of the following drugs intraperitoneally—pemetrexed (50 mg/kg), imatinib (50 mg/kg), erlotinib (25 mg/kg), meropenem (60 mg/kg), 6-mercaptopurine (20 mg/kg) and voriconazole (6 mg/kg). Blood samples were collected 2 h after dosing (1 h in 6-mercaptopurine group due to short half-life) by terminal bleeding from the retro-orbital plexus. Blood was collected in each of Disodium ETDA, heparin, trisodium citrate (TSC) and no anticoagulant (plain) tubes. Drug levels in these samples were determined by validated HPLC assays. ANOVA with Tukey’s post hoc test was performed to identify statistically significant differences in drug concentrations in anticoagulant tubes. p < 0.05 was considered statistically significant.ResultsSignificant differences in concentration between anticoagulant tubes was observed in case of erlotinib (p = 0.013) and meropenem (p = 0.00), while borderline statistical significance for pemetrexed (p = 0.076). TSC tubes overestimated erlotinib levels, heparin tubes underestimated meropenem concentrations and EDTA tubes overestimated pemetrexed concentrations.ConclusionsCareful selection of anti-coagulant is necessary for accurate characterization of pharmacokinetics of drugs. Routine use of EDTA tubes may lead to erroneous interpretation of pharmacokinetic data.Electronic supplementary materialThe online version of this article (doi:10.1186/s40064-016-3770-4) contains supplementary material, which is available to authorized users.

Highlights

IntroductionWhile blood samples can be collected either in EDTA, heparin or citrate containing tubes for the estimation of drug levels in plasma, EDTA tubes are more commonly used
Pharmacokinetic studies are vital in development and optimization of drugs
If doses are modified based on incorrectly reported drug levels, it could lead to sub-therapeutic levels or potential toxicity

Summary

Introduction

While blood samples can be collected either in EDTA, heparin or citrate containing tubes for the estimation of drug levels in plasma, EDTA tubes are more commonly used. Blood was collected in each of Disodium ETDA, heparin, trisodium citrate (TSC) and no anticoagulant (plain) tubes. Drug levels in these samples were determined by validated HPLC assays. Accurate determination of drug levels in human blood samples in clinical trials and routine patient care is extremely important. For anticancer drugs and some anti-microbials with narrow therapeutic window and high toxicity, appropriate determination of analyte is vital for TDM (Chantry et al 2014; Marquet and Rousseau 2008; Paci et al 2014)

Objectives

Methods

Results

Conclusion