High performance electrode based on platinum nanoparticle-silicon nanowire nanohybrid and aptamer for detection of Escherichia coli

A high-performance electrode based on platinum nanoparticle-silicon nanowire (PtNP@SiNW) nanohybrid and Escherichia coli (E. coli) aptamer was developed and used for detection of E. coli. The E. coli in the test solution could be adsorbed specifically onto the electrode surface by the aptamers modified on the PtNP@SiNW nanohybrids and influence the electron transfer between the electrode and the electrolyte, based on which the electrochemical assay of E. coli was achieved. The sensing system showed a good linearity in the testing concentration range (1.3 x 10(2)-3.6 x 10(5) CFU/mL) with a high sensitivity (1.17 mu A/lg C-E. coli). The nanostructured PtNP@SiNW hybrid was revealed to play an important role in performance enhancement. Furthermore, the biosensor also exhibited fast response, good selectivity and stability. This high-performance PtNP@SiNW nanohybrid-aptamer-based electrode has great potential for future practical applications in the field of foodborne pathogenic bacteria detection.