Engineering Cu-β-CD/T-PDs+D-PANI/GCE sensing platform for efficient electrochemical recognition of tryptophan enantiomers.

Chiral recognition plays an important role in safeguarding the health of human beings, and the construction of chiral analytical sensing platforms with high specific discrimination capability is essential. Herein, an electrochemical sensor of Cu-β-CD/T-PDs + D-PANI/GCE was designed for the enantioselective recognition of tryptophan (Trp) enantiomers by coating the composites of polymer dots (T-PDs) and d-polyaniline (D-PANI) along with Cu-β-cyclodextrin (Cu-β-CD) on the surface of glassy carbon electrode (GCE). Owing to sufficient specific binding site, large active area and excellent electron transfer efficiency of the modification chiral materials, the proposed sensing platform obtained a satisfactory enantioselectivity coefficient (IL/ID) of 2.23, and the detection limits (LOD) for L-Trp and D-Trp were 0.677 and 3.443 μM, respectively. Additionally, this sensing platform was able to analyze the percentage of L-Trp in enantiomer mixtures and has the characteristics of real sample analysis with good accuracy and reproducibility.