Figure 4.

Detection of blaCTX-M-15 gene by the BiMW biosensor. (A) Schematic representation to detect both DNA strands using forward and reverse probes. (B) Real-time detection of blaCTX-M-15 gene at 4.5 fM (black line), non-specific Pseudomonas aeruginosa at 3.4 fM (blue line), and Escherichia coli without blaCTX-M-15 gene at 2.9 fM (red line). (C) Real-time interferometric signals of blaCTX-M-15 at several concentrations (0.45–4.5 fM). (D) Calibration curve obtained for the range of concentrations analyzed. The curve was fitted to a linear regression (y = a + bx, R² = 0.994). All the measurements were performed in triplicate, and the data are shown as the mean + SD.