GIỚI HẠN ĐỊNH LƯỢNG MỚI CỦA PHƯƠNG PHÁP ĐO NỒNG ĐỘ ETHANOL TRONG MÁU TRÊN MÁY SINH HÓA TỰ ĐỘNG COBAS C503

Abstract

Objective: To validate and establish the new limit of quantification (LoQ) for the method of blood ethanol concentration measurement using alcohol dehydrogenase enzyme on the Cobas c503 automatic biochemistry analyzer. Subjects and methods: Method validation was performed to determine the new limit of quantification  (LoQ) using ethanol serum samples, quality control (QC), and calibration (Calib) provided by the manufacturer. The validation parameters, which include limit of blank (LoB), limit of detection (LoD), limit of quantification (LoQ), linearity, precision, and trueness, were determined according to Clinical and Laboratory Standard Institute (CLSI) guidelines. Results: The LoB and LoD were established at 1,97 mg/dL and 3,42 mg/dL, respectively. The LoQ was determined to be 5 mg/dL, with a total error of the method (TE_PXN%) lower than the allowable total error (TEa%) (18,24% < 20%). The calibration curve demonstrated a linear relationship described by the equation ŷ= 1,0192x, in the range of 5 – 216 mg/dL with R = 0.9997. Both the precision and trueness met the criteria required by CLSI guidelines. Conclusion: The method of ethanol quantification in blood on the Cobas c503 system determined a new limit of quantification (LoQ) of 5 mg/dL according to CLSI with the new establishment of LoB, LoD, and LoQ, ensuring accuracy, reliability, and suitability for clinical laboratory practice.