In vitro monitoring of i-NOS concentrations with an immunosensor: the inhibitory effect of endocrine disruptors on i-NOS release

The amperometric immunosensor has demonstrated the toxicity of endocrine disrupters (EDs) through monitoring the in vitro i-NOS concentration change, where the antibody of inducible nitric oxide synthase (i-NOS) was immobilized on the conducting polymer-gold nanoparticles composite. The performance of the sensor and the experimental parameters affecting the immunoreaction were optimized. Neuronal cells treated by EDs decreased in the in vitro i-NOS concentration. The effect of bisphenol A (BPA) on the i-NOS concentration released in the cells was investigated with different incubation times, and the interfering by nonspecific binding species present in a neuronal cell lysate was also examined. Of all the tested EDs, BPA showed the inhibitoriest effect and the minimum inhibitory concentration of BPA affecting the i-NOS concentration was 0.09 ± 0.005 μM. The result shows that monitoring of i-NOS in the neuronal cells treated by EDs will be a useful method to evaluate the toxic behavior of EDs.