Abstract
OBJECTIVE: To investigate the method of loop-mediated isothermal amplification (LAMP) using boiled serum for visual detection of hepatitis B virus (HBV). METHODS: Specific LAMP primers were designed according to the conservative region compared with the sequence of S genes in GenBank, and DNA of the samples was extracted by kit and boiling methods. The reaction conditions of LAMP were optimized, and HBV standard strains and clinical samples were examined to evaluate the specificity, sensitivity, and anti-interference ability of LAMP. Visual detection was performed for the results of LAMP, and SPSS 17.0 was used for consistency test. RESULTS: The optimal reaction conditions of LAMP were established. LAMP had a high specificity, and there was no nonspecific amplification. The sensitivity of LAMP was 10 copies/tube, regardless of the method for nucleic acid extraction. Hydroxynaphthol blue (HNB) had a comparable sensitivity to electrophoresis and SYBR Green I, and, unlike SYBR Green I, did not cause aerosol pollution easily. In addition, with fluorescent quantitative PCR (FQ-PCR) as the gold standard, LAMP using the boiling method and FQ-PCR were in good consistency (Kappa = 0.762, P > 0.05). However, PCR using boiling method was not well consistent with FQ-PCR (Kappa = 0.186, P < 0.05). CONCLUSION: LAMP has certain advantages over PCR in detecting HBV infection, and LAMP can be used to detect HBV in the field or primary hospitals.