Abstract: Present invention deals with a new immuno-reagent comprising hapten (MPAD)-protein-gold for pesticides detection. The conjugate MPAD-protein-gold competes with the analyte of interest for a finite number of binding sites provided by anti-atrazine antibodies coated on nitrocellulose membrane. The newly developed conjugate has a long shelf life with high stability at 4° C. The dynamic concentration range for standard atrazine solutions shows a linear inhibition (decrease in intensity of color) between 10 ppb to 1 ppm atrazine in water samples.

Abstract: A biosensor system includes a functionalized interdigitated electrode, functionalized nanoparticles, a current/voltage signal generator, and a circuit analyzer. The interdigitated electrode can be functionalized by coating an exposed surface with first biomolecular probes. The nanoparticles are functionalized by coating an outer surface with second biomolecular probes. A signal generator provides a signal (e.g., an alternating current or voltage) having a selected range of frequencies. A circuit analyzer analyzes electrical parameters of the circuit as the signal is applied. Sensitivity is increased by the presence of functionalized nanoparticles in the system. An analytic method includes measuring changes in electrical parameters of the circuit over the range of frequencies. Using these measurements, the biosensor system can determine whether a target biomolecule is bound.