Fig. 4From: Development of a new method based on unmodified gold nanoparticles and peptide nucleic acids for detecting bovine viral diarrhea virus-RNA a Visual color changes of developed detection assay at different BVDV-RNA concentrations. Wells 1–7 contain 0, 1.64, 3.27, 6.55, 13.1, 26.2, and 52.4 ng/reaction of RNA respectively. b Plot of linear correlation (R2 = 0.992) of absorbance 520/620 nm ratio vs. different concentrations of viral RNABack to article page