Establishment of ultra performance liquid chromatography-tandem mass spectrometry method for measuring plasma caffeine concentration / 中华检验医学杂志

ABSTRACT

Objective:To establish an ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for plasma caffeine concentration detection, and to explore the clinical value of caffeine therapeutic drug monitoring (TDM) in the treatment of premature infants with respiratory distress syndrome (RDS).Method:Take the plasma sample in a centrifuge tube, add the caffeine deuterated isotope internal standard, then add the protein precipitant, vortex the mixture thoroughly, and centrifuge the supernatant to enter the mass spectrometry analysis. The mobile phase were methanol and water, gradient elution; the column temperature was 45 ℃, the method was established using Shimadzu LC-30AD-CL liquid system and AB SCIEX 4500 QTRAP mass spectrometer, and the sensitivity, specificity, linearity, accuracy imprecision, matrix effect, and carry-over of the method were evaluated. Sample from 30 patients diagnosed with neonatal RSD were collected in the Department of Neonatology of Renmin Hospital of Wuhan University from February to April 2021, then detected the trough concentration of caffeine in premature infants with RDS after taking the same dose of caffeine to assess the impact of individual variation on caffeine drug concentration.Results:The detection limit of caffeine was 0.02 μg/ml, and the lowest limit of quantification was 0.05 μg/ml. It showed good linearity ( R2=0.9986, R>0.99) in the concentration range from 1.0 to 100.0 μg/ml, specificity (recovery rate of 85.52%-114.12%), accuracy (recovery rate 85.97%-114.53%), intra-day and inter-day imprecision ( CV 6.01%-11.28%), matrix effects and carryover pollution were negligible. The trough concentration of 30 preterm infants with RSD after taking the same dose of caffeine (10 mg/kg) was (25.45±11.61) μg/ml, and the coefficient of variation was 44.88%. Conclusion:This study established an accurate and reliable UPLC-MS/MS method with low sample consumption to monitor the blood concentration of caffeine; caffeine TDM has certain clinical application value, which can be used to assist RDS diagnosis and treatment and improve the efficacy of caffeine.