MIL-53(Fe)-derived ant nest structured porous carbon nanospheres CuFeS2 /C for the determination of atropine enantiomeric impurity L-hyoscyamine.

Abstract

In this work, an ant nest structured porous carbon nanosphere had been developed for the recognition detection of the atropine (ATP) enantiomers D-hyoscyamine (D-HSM) and L-hyoscyamine (L-HSM). Firstly, Fe-based organic framework was used as the substrate, and Cu ions and sulfur ions were separately introduced to obtain CuFeS2 with ant nest structure by hydrothermal incubation. Then CuFeS2 /C porous nanospheres (PNSs) were obtained by high-temperature calcination. The composite-modified electrode exhibited superior electrochemical performance for L-HSM due to the synergistic effect of CuFeS2 cubic crystals and porous carbon, which has the high specific surface area of the ant nest structure. In addition, the molecularly imprinted polymer (MIP) about L-HSM formed with sulfonated-β-cyclodextrin (S-β-CD) and L-arginine (L-Arg) by cyclic voltammetry showed strong chiral recognition of D/L-HSM (ATP). Therefore, a novel electrochemical sensor was constructed based on CuFeS2 /C PNSs and MIP to detect L-HSM by differential pulse voltammetry. Under the optimal conditions, the peak current density of L-HSM showed a good linearity in the concentration range of 0.02-4.6μM with LOD and LOQ of 0.45 and 1.5nM, respectively. The oxidation peaks of L-HSM and D-HSM were successfully identified from the racemic ATP, and the oxidation peak potential difference (ΔEp ) between them was 0.138 V. In conclusion, the sensor showed excellent reproducibility, repeatability, and stability and had been applied to the determination of L-HSM in human serum, saliva, and ATP sulfate tablets with satisfactory results.