Abstract
OBJECTIVE: To investigate the rapid and accurate method for the detection of dengue virus (DENV) by using nicking enzyme assisted strand-displacement amplification (SDA) combined with gold nanoparticles-based lateral flow strip. METHODS: Total RNA of the virus was extracted by using magnetic beads method and transcribed to cDNA for SDA detection system. Nicking enzyme-assisted method was used for detecting DENV, and agarose gel electrophoresis was used for analyzing the sensitivity of SDA amplification products. A gold nanoparticles-based lateral flow strip was developed based on the principle of nucleic acid base complementary pairing to design the test line and control line. The gold particles were prepared by using sodium citrate reduction method for gold nanoparticles-based lateral flow strip construction. RESULTS: The sensitivity of the SDA method was 10 fmol/L, and the sensitivity of gold nanoparticles-based lateral flow strip based on SDA method was also 10 fmol/L. In a linear range from 10 fmol/L to 10(12) fmol/L, the corresponding linear correlation coefficient (R(2)) of DENV was 0.98. The specificity of nanoparticles-based lateral flow strip based on SDA for DENV detection was high, which was no crossing with other control groups. CONCLUSIONS: A gold nanoparticles-based lateral flow strip based on SDA method for DENV detection has been established, which is convenient, fast, and the result is visible to naked eyes.