DETERMINATION OF PARAQUAT IN PLASMA AND URINE BY MICELLAR LIQUID CHROMATOGRAPHY

• Main Author: Leelakunakorn W.
• Other Authors: Mahidol University
• Format: Article
• Published: 2023
• Subjects: Medicine
• Online Access: https://repository.li.mahidol.ac.th/handle/123456789/83051

The study aimed to apply micellar liquid chromatography (MLC) to detect paraquat levels in human plasma and urine samples at a medical decision level for suspected poisoning, which is not achieved by the current ion-pairing LC method. Paraquat in (acid-treated) human plasma and urine samples was analyzed using C18 Eclipse XDB column maintained at 30°C and an aqueous micellar mobile phase (pH 3.0) composed of 50 mM sodium dodecyl sulfate, 15% (v/v) acetonitrile, 0.5% (v/v) diethylamine, and 9% (v/v) n-butanol, with paraquat monitored by measuring absorbance at 258 nm. The limit of detection of plasma paraquat (PPQ) and urine paraquat (UPQ) was 0.02 and 0.05 μg/ml respectively; and the limit of quantification was 0.05 and 0.16 μg/ml respectively. Dynamic range for both PPQ and UPQ was achieved at 0.16-100 μg/ml and recovery of spiked (2-10 μg/ml) PPQ and UPQ samples ranged from 100.4-102.9%. Within run repeatability of PPQ and UPQ, detection was obtained at 1.8 and 3.5% relative standard deviation (RSD) respectively and within laboratory repeatability of 4.16 and 7.31% RSD respectively, with a turn-around time of eight minutes. In conclusion, the MLC method was capable of detecting paraquat at a medical decision level for suspected poisoning, namely, 0.2 and 0.9 µg/ml in plasma and urine respectively.