Rapid analysis of intraperitoneally administered morphine in mouse plasma and brain by microchip electrophoresis-electrochemical detection.

ABSTRACT: Animal studies remain an essential part of drug discovery since in vitro models are not capable of describing the complete living organism. We developed and qualified a microchip electrophoresis-electrochemical detection (MCE-EC) method for rapid analysis of morphine in mouse plasma using a commercial MCE-EC device. Following liquid-liquid extraction (LLE), we achieved within-run precision of 3.7 and 4.5% (coefficient of variation, CV, n?=?6) and accuracy of 106.9% and 100.7% at biologically relevant morphine concentrations of 5 and 20?µM in plasma, respectively. The same method was further challenged by morphine detection in mouse brain homogenates with equally good within-run precision (7.8% CV, n?=?5) at 1?µM concentration. The qualified method was applied to analyze a set of plasma and brain homogenate samples derived from a behavioral animal study. After intraperitoneal administration of 20?mg/kg morphine hydrochloride, the detected morphine concentrations in plasma were between 6.7 and 17?µM. As expected, the morphine concentrations in the brain were significantly lower, ca. 80-125?nM (280-410?pg morphine/mg dissected brain), and could only be detected after preconcentration achieved during LLE. In all, the microchip-based separation system is proven feasible for rapid analysis of morphine to provide supplementary chemical information to behavioral animal studies.

SUBMITTER: Ollikainen E 

PROVIDER: S-EPMC6397260 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature