RESUMEN
This study developed an online solid-phase extraction ultra-high performance liquid chromatography-tandem mass spectrometry (Online-SPE-UHPLC-MS/MS) method for the analysis of 28 illegal drugs in sewage. To achieve this, 28 isotope internal standards (ISTDs) were added to 3 mL sewage samples, the pH was adjusted to 7-8 using hydrochloric acid or 20% ammonia water, followed by centrifugation, filtration, and analysis using UHPLC-MS/MS. The results indicated an excellent linearity of 1-300 ng L-1, and cotinine in the concentration range of 20-6000 ng L-1, linear correlation coefficient R2 > 0.995, with the limit of detection (LOD) of 0.01-6 ng L-1, and a limit of quantification (LOQ) of 0.1-20 ng L-1. The addition of three concentrates of low (2 ng L-1/40 ng L-1), medium (20 ng L-1/400 ng L-1), and high concentration (200 ng L-1/4000 ng L-1) demonstrated the matrix effect of the target compound between ± 22.0%. The extraction recovery was 70.0-119.4%, and a percent accuracy of 75.7-118.1%. Similarly, the intra- and inter-day precisions were 1.8-20.0% and 1.5-18.9%, respectively. The results cemented the sensitivity, accuracy, reliability, strong specificity, and reproducibility, which can be used to screen 28 illegal drugs in sewage for trace analysis.
RESUMEN
Toxic alkaloids are typically found in herbal medicines and have strong pharmacological effects and a broad therapeutic spectrum. On the other hand, toxic alkaloids exert toxicological activities in vivo; as such they have a narrow therapeutic window and can induce poisoning due to incorrect dose or misuse. In this view, there is an urgent need to develop a rapid and sensitive assay to detect these toxic alkaloids. This study developed a method for determining five common toxic alkaloids in blood, including brucine, strychnine, aconitine, mesaconitine, and hypaconitine using ultra-high liquid chromatography-tandem quadrupole/linear ion trap mass spectrometry (QTRAP UPLC-MS/MS). The analytes in this investigation were extracted with ether and detected using multiple reaction monitoring (MRM)-information-dependent acquisition (IDA)-enhanced product ion (EPI) scanning modes. SKF525A served as the internal standard (IS). The approach demonstrated excellent linearity, with a correlation coefficient (R) > 0.9964, and satisfactory sensitivity, with the limit of detection (LOD) of 0.31 â¼ 3.26 ng/mL and a limit of quantification (LOQ) of 1.13 â¼ 11.52 ng/mL. The extraction recovery (ER) was 78.8 â¼ 116.2%, the matrix effect (ME) was -12.3 â¼ 21.2%, and the method accuracy was 0.8 â¼ 12.8%. In addition, the intra-day precision and the inter-day precision (RSD) were 0.7% â¼ 7.4% and 0.4% â¼ 13.5%, respectively. The developed approach is sensitive and efficient, and offer significant application prospect in clinical monitoring and forensic detection of poisoning.