Simultaneous determination of aesculin and aesculetin and their interactions with DNA using carbon fiber...

Electrode sensitivity and selectivity in complex biological matrices are major challenges in the development of electrochemical sensors. Bimetallic nanoparticles provide a new perspective for enhancing electrocatalytic property because of some specific synergetic effects. In this work, platinum nanoparticles (PtNPs) and gold nanoparticles (AuNPs) modified carbon fiber microelectrode (PtNPs/AuNPs/CFME) was fabricated to determine aesculin and aesculetin simultaneously. Differential pulse voltammetry (DPV) method was conducted for the electrochemical sensing of aesculin and aesculetin, the modified electrode displayed high electrocatalytic activity for the redox of these two drugs. The linear ranges of aesculin and aesculetin were 0.4-10 μM and 0.04-1 μM, with the detection limits of 41 nM and 3.6 nM, respectively, which were the lowest values achieved. Furthermore, an electrochemical investigation of the interactions of these two drugs with Calf thymus double stranded DNA (dsDNA) was investigated by PtNPs/AuNPs/CFME, the decrease in peak currents is proportional to DNA concentration and can be used to detect DNA. The electrode was successfully used to measure aesculin and aesculetin in mouse serum and urine with 98.0-104.8% recovery. The novel electrochemical probe possessed excellent performances of high sensitivity, good reproducibility, and simplicity of fabrication, which will facilitate effective detection of aesculin and aesculetin for metabolic kinetics study.