Figure 4.

Comparison of Trizol LS and High Pure Viral RNA isolation kits in the isolation of viral RNA from DENV-3 infected patient sera. A volume of 50 μl of serum samples from dengue-infected patients were re-suspended in 150 μl of human serum (A) or PBS (B), and the viral RNA isolated using either TRIzol LS in the presence of linear acrylamide, or the High Pure Viral RNA isolation kit. The viral RNA was then quantified using the DENV-3 TaqMan real-time PCR assay in parallel with in vitro transcribed RNA standards. All experiments were done in quadruplicate and assayed in duplicate. The data are expressed as mean ± SEM. The asterisks denote statistical significance (paired Student's t-test, *P < 0.01; **P < 0.005).