Silver Microneedle Array Printed via Aerosol Jet Enhance the Electrochemical Detection of Carboxylated Carbon Nanotubes for Chloramphenicol

Chloramphenicol (CAP) is a potent broad-spectrum antibiotic that has been restricted for use in food producing animals in many countries due to its serious side effects. Therefore, there is an urgent need for rapid and sensitive detection of CAP. In this study, three-dimensional electrochemical sensing electrode with high sensitivity to CAP was developed, which consisted of aerosol jet printed silver microneedle modified by carboxylated multi-walled carbon nanotubes (MWCNTs-COOH). The silver microneedle arrays provide a three-dimensional porous structure and rapid electron transfer pathways for MWCNTs-COOH. As a result, the obtained SPCE/Ag<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">10×10</sub>@CNTs electrode exhibits a limit of detection (LOD) of 0.073 μM and a high sensitivity of 18.86 μA/(μM·cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>) towards CAP. The modified electrode demonstrates excellent selectivity, stability, reproducibility, and repeatability towards CAP. Moreover, the electrochemical sensor was applied to determine CAP in real samples with satisfactory results.