Electrochemical aptasensor based on gold nanoparticle decorated TiCT nanocomposites for chloramphenicol detection.

Using gold (Au) nanoparticle decorated TiCT (TiCT-Au) nanocomposites, a highly sensitive electrochemical aptasensor for the effective detection of chloramphenicol has been developed. As a two-dimensional layered material, the prepared composite not only provides high surface area, good conductivity, and thermal stability but also substantial binding sites for aptamers with high sensitivity and selectivity for the accurate determination of chloramphenicol. Interestingly, the conductivity and active sites were enhanced by freeze-drying TiCT and in situ formation of TiCT-Au nanocomposite. The fabricated aptasensor exhibited a very low detection limit (S/N ≥ 3) of 13.18 fg mL with a linear range of 1 ~ 700 pg mL and correlation coefficient of 0.9992. The fabricated aptasensor demonstrated an excellent reproducibility, repeatability, long-term stability, and high selectivity toward chloramphenicol. Further, the aptasensor was applied to real milk samples, and the recoveries were ranged from 98.93 to 101.93%.