1.Simultaneous determination of 18 organophosphorous and carbamate pesticides in human plasma by UPLC-MS/ MS
Peng LI ; Zexin BAI ; Qiujin XIAHOU ; Fei GUO ; Wenji BI
Chinese Journal of Forensic Medicine 2017;32(1):51-54
Objective To develop a method for determination of 18 organophosphorous and carbamate pesticides in human plasma by UPLC-MS/MS. Methods Following deproteinization by acetonitrile, an aliquot of the biological sample was injected into a C18 column(1.7μm 2.1×50mm) using 5mmol/L Ammonium acetate-methanol as the mobile phase with the flow rate of 0.3mL/min, the injection volume was 10μL. Electro spray ionization(ESI) Indicators source was applied and operated in positive ion mode, and multiple reaction monitoring(MRM) mode was used to quantify. Results The limits of detection(LODs) in human plasma ranged from 0.1 to 40ng/mL, and the limits of quantitation(LOQs) ranged from 0.5 to 50ng/mL. An excellent linearity was observed for these LOQs up to 50ng/mL. The average extraction recoveries were with in 64.3%~111.9%, relative standard deviation(RSD) is 3.9%~10.3%. Conclusion This method is specific, sensitive and accurate, and can be used to detect pesticides in forensic.
2.Problems in detecting CK19 mRNA with RT-PCR and corresponding countermeasures
Jianwei BI ; Wei JING ; Jun ZHANG ; Wenji LI
Academic Journal of Second Military Medical University 1981;0(03):-
Objective:To search for a better RT-PCR method for detecting CK19 mRNA. Methods: RT-PCR methods were used to detect the expression of CK19 mRNA in the tumor tissues and in the peripheral blood of patients with gastric cancer and in the peripheral blood of healthy subjects. Results: The influence of pseudogene and genome was observed through nonreversely transcripted RNA controls and comparison of several pairs of primers.The interference could be effectively eliminated by regulating the annealing temperature based on mismatched primers. Conclusion: The presence of pseudogene and genome interferes the experimental protocol in RT-PCR,which can be resolved with the method introduced in our paper.