Systematic literature review of different methods for sample preparation for the quantification of coenzyme Q10 in human blood samples by HPLC

Abstract Quantification of coenzyme Q10 (CoQ10) is used to diagnose a CoQ10 deficiency and to monitor the CoQ10 level in patients. Therefore, an accurate, quick and simple determination method is a frequently required standard procedure in clinical laboratories. The gold standard for quantification of coenzyme Q10 is the use of high pressure liquid chromatography (HPLC). Before the instrumental quantification of CoQ10, a careful and complex sample preparation is required. There are several reported variations between sample preparation methods in the literature. The online database PubMed was searched for published HPLC methods for the quantification of CoQ10 through May 2024. We included publications describing a HPLC method with UV detection for the quantification in human blood, serum and plasma. 328 reports were screened from the database PubMed. Thereof, 19 methods to quantify coenzyme Q10 were selected and summarized in a table presenting the sample preparation procedure, HPLC settings and reporting of quality criteria. Three reports were rated as having high quality and their methods are presented in detail and compared with each other. This report provides a tabular overview of the various sample preparation options for the quantification of coenzyme Q10 in human blood samples (plasma, serum) using HPLC in combination with a UV detector. It enables the user to screen methods for similarities and differences and represents a tool for method development and method establishment to quantify coenzyme Q10 in a laboratory.