Comparative Study of Electrochemical Biosensors Based on Highly Efficient Mesoporous ZrO2-Ag-G-SiO2 and In2O3-G-SiO2 for Rapid Recognition of E. coli O157:H7

摘要

Here, we reported an innovative and electrochemical biosensor for the rapid detection of Escherichia coli O157:H 7. We fabricated the mesoporous ZrO_(2)-Ag-G-SiO_(2) (ZAGS) and In_(2)O_(3)-G-SiO_(2) (IGS) sensors, and cyclic voltammetry (CV) was employed to detect the bacteria. The development of these portable sensors addresses the challenges of conventional time-consuming and more expensive laboratory-based analyses. Hence, the biosensors were highly selective to detect E. coli . The sensor could recognize an individual E. coli cell in 1 μL of sample volume within 30 s. E. coli live cells tied down on sample nanoparticles worked toward the definite acquirement of E. coli . The high thickness of negative charge on the surface of E. coli cells effectively regulated the concentration of dominant part charge carriers in the mesoporous channel, allowing a continuous check of E. coli concentration in a known sample. The signal current decreased linearly, while the E. coli concentration increased from 1.0 × 10~(1) to 1.0 × 10~(10) CFU/mL. ZAGS and IGS biosensors could detect E. coli in the range from 10~(1) to 10~(10) CFU/mL. ZAGS and IGS biosensors in this investigation showed great specificity, reproducibility, stability, and selectivity and are expected to have a great impact on applications in the detection of foodborne pathogens.