To optimize dual molecular beacon detection system for rapid identification of Mycobacterium tuberculosis / 国际检验医学杂志

ABSTRACT

Objective To optimize the experimental system of dual molecular beacon to rapidly detect My-cobacterium tuberculosis and its resistant strains.Methods Fluorescence quantitative PCR was carried out by selecting different magnesium ion concentration,annealing temperature and primer concentration respectively. Finally,the optimum reaction conditions were obtained.Results In order to ensure the efficiency of amplifica-tion and no non-specific amplification,the final selection of the best conditions were as follows,the concentra-tion of Mg2+was 3.0 mmol/L,annealing temperature was 60 ℃,and the concentration of primers was 0.3 mmol/L.Conclusion The optimal condition of dual molecular beacon experiment was established,which en-sured that the detection of Mycobacterium tuberculosis by molecular beacon quantitative PCR had the advanta-ges,such as simple operation,rapid speed,high sensitivity(the minimum detection limit was 1 CFU/mL)and specificity(only Mycobacterium tuberculosis complex including drug-resistant strains could be detected),good reproducibility(coefficient of variation was < 5%)and other advantages.The study provides the necessary conditions for the dual molecular beacon detection of Mycobacterium tuberculosis.