LC-MS/MS method for screening of intoxication and drug adherence of angiotensin-converting enzyme inhibitors in plasma.

Aim: Intentional and accidental drug intoxication as well as medication adherence require sensitive and reliable analytical screening methods. Such methods are often lacking in children and adults, therefore, a reliable analytical method has been developed by using low plasma volume. Materials & methods: Sample preparation from plasma was achieved by solid-phase extraction process. LC-MS in positive ion mode was performed using X-select CSH™ C18 column. The mobile phase consisted of water and acetonitrile acidified with 1% formic acid using a gradient method with total run time of 10 min. Results: The method showed repeatability for all analytes. The linearity range from 0.78 to 100 ng/ml per analyte was established with recoveries ≥87% and matrix effect for all analytes was within guideline limits. Conclusion: The screening method was successfully validated for monitoring of intoxication and medication adherence of ten analytes in 50 μl residual plasma samples of children and adults.