Fig 1.
Illustration of HBV DNA extraction by UF.
Fig 2.
Effects of serum protein removing by different methods.
Figures showing the generation of precipitant after treating the serum samples with NaOH, proteinase K, SDS-KAc and phenols, respectively (left), and concentrates obtained from the supernatants by ultrafiltration (right). NWML of the ultrafiltration device used was 100K.
Fig 3.
OD260/280 ratioof DNA samples prepared using various methods.
Fig 4.
Recovery of HBV DNA using UF devices with different NWMLs, magnetic beads and column.
(A) The recovery rates of high-titer (6.3 log10 IU/ml) and low-titer (4.2 log10 IU/ml) HBV samples using the UF devices of different NWMLs; (B) The recovery rates of HBV DNA obtained using magnetic beads method; (C) The recovery rates of HBV DNA obtained using the DNA-extraction column method; (D) Adsorption amount of the HBV DNA on the filter devices (30K, 50K and 100K). Samples used were purified HBV DNA of different concentration (20, 100 and 200 ng/μl). The devices were placed at room temperature for 1h before detection.
Fig 5.
(A) CVs of the DNA quantitation of High-titer (6.3 log10 IU/ml), low-titer (3.2 log10 IU/ml) and limit-titer (10 IU/ml). The QS samples were treated using UF devices with 100K NWML; (B) Linearity of HBV DNA quantitations determined using the UF-qPCR assay. Samples used were serial dilutions of a high-titer HBV clinical specimen; (C) Correlation analysis of HBV DNA quantitative results (n = 40) between UF-qPCR and CAP-CTM V2.0 assay system. (D) Consistency of UF-qPCR and CAP-CTM V2.0. The difference between UF-qPCR and CAP-CTM V2.0 measurements is plotted as a function of the mean of these two values. The area between the dashed lines corresponds to the mean difference ±1.96 SD.
Table 1.
LOD of the UF-qPCR assay determined by analyzing HBV QS serum samples.
Table 2.
Comparison of the UF-qPCR and the CAP-CTM V2.0 method.