Fig. 2
From: City-scale monitoring of antibiotic resistance genes by digital PCR and metagenomics
dPCR of tetW and sul2 antibiotic resistance genes. dPCR primers and probes designed for the ARGs tetW and sul2 were first tested by qPCR (same conditions as the dPCR) in the Hospital wastewater sample, and the PCR products were observed in an electrophoresis gel. Then, a chip-based dPCR was run for both genes and different water samples. Only dPCR results with precision ≤ 10% were considered for our results as recommended for dPCR standards, similarly to qPCR best practices. To verify the proper amplification of the dPCR product, a second PCR (nested PCR) was run with the primers, and the product was analyzed by gel electrophoresis (TBE, 2%) to ensure the expected size of dPCR product. Ladder used: Gene Ruler 1 kb+. This confirms that the detection signal obtained from probes using during dPCR was fully specific as shown in the histogram and dot plot of dPCR detection of targeted genes (blue color)