Liquid crystal 5CB-loaded nanogold as new nanocatalyst combined with aptamer to determine small organic pollutants by Cu2O resonance Rayleigh scattering probe

A new, highly catalysis and stable liquid crystal 5CB-loaded nanogold (Au/5CB) nanosol was prepared through template method and was characterized in details. It was found that Au/5CB can strongly catalyze the new indicator reaction of fructose-Cu(II) tartrate complex to generate Cu 2 O cube particles (CPs) with high resonance Rayleigh scattering effect. Combined the nanocatalytic amplification indicator reaction with the label-free aptamer (Apt) reaction, a new RRS aptasensing platform was developed to detect 0.05–1.0 ng mL −1 oxytetracycline (OTC) and the limit of detection was 0.02 ng mL −1 . The developed RRS aptasensing platform can be also utilized to detect 7.5–60 ng mL −1 malathion and 1–3.5 ng mL −1 tetracyclines. Finally, the nanocatalytic reaction mechanism was studied.