Chiral recognition of penicillamine enantiomers using hemoglobin and gold nanoparticles functionalized graphite-like carbon nitride nanosheets via electrochemiluminescence.

A new stable and stereo-selective electrochemiluminescence (ECL) interface has been designed for specific recognition of penicillamine (Pen) enantiomers by using hemoglobin (Hb) and gold nanoparticles functionalized graphite-like carbon nitride nanosheets composite (Au-g-C3N4 NHs) modified glassy carbon electrodes (Hb/Au-g-C3N4/GCE). The advantages of Hb as chiral selector and Au-g-C3N4 NHs as luminophore were perfectly displayed in this novel interface. The obviously different ECL intensity was exhibited after l-Pen and d-Pen adsorbed on Hb/Au-g-C3N4/GCE, and a larger response was observed on d-Pen/Hb/Au-g-C3N4/GCE. Under the optimum conditions, the developed ECL chiral sensor showed excellent analytical property for detection of Pen enantiomers in a linear range of 1.0×10-4M to 5.0×10-3M, and the detection limits of l-Pen and d-Pen were 3.1×10-5M and 3.3×10-5M (S/N=3) respectively. This work with high selectivity, stability and reproducibility may open a new door based on ECL to discriminate Pen enantiomers.