Abstract
A novel electrochemical aptasensor modified with the nanocomposite of porous carbon nanospheres and Au urchins as the signal amplification and immobility platforms for aptamer was successfully constructed for ultrasensitive and selective determination of streptomycin. The streptomycin aptamer was fixed on the surface of the nanocomposite via the strong Au-S bond between Au urchins and aptamer. The target binding-induced conformational change of aptamer resulted in signal attenuation, which was expressed as "Delta I = I-BSA - I-streptomycin." Based on the synergic signal amplification platform, P: 203 8 109 20 O : Thu 30 Mar 2023 12:58:34 the as-prepared aptamer-based sensor showed a wider liearity to streptomycin from 0.01 to 350 ng/mL with a low Copyright American Scienti ic Publisher detection limit of 5.0 pg/mL under the optimized condition. Finally, the aptasensor was operated in milk and honey to Delivered by Ingenta detect streptomycin. This study has provided a facile way to develop highly sensitive, effective and efficient aptamer-based electrochemical sensors for the detection of antibiotics at very low concentration.