Figure 4: Calibration curves for the detection of TTX in SAB at pH 4.5 and pufferfish liver extract, pufferfish muscle extract, and urine diluted to 10% in SAB at pH 4.5. Normalized SPR resonant wavelength shift versus the concentration of TTX incubated with 2 μg/mL anti-TTX for 15 minutes by an inhibition assay. The data from the sensorgram was normalized to the maximum anti-TTX response in SAB.