Host–guest sensing towards sodium cyclamate based on a cationic pillararene reduced graphene nano-composite†
In this paper, the host–guest recognition and sensing between macrocyclic pillararene (CP6) and sodium cyclamate (SC) is first researched. A fluorescent sensing platform is fabricated with CP6 modified reduced graphene (CP6-RGO) as the receptor and the probe rhodamine B (RB), which shows high selectivity and sensitivity for the detection of SC. The structure of the CP6-RGO nano-material is confirmed by transmission electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared and thermogravimetric analysis. The mechanism of host–guest recognition between CP6 and SC is also investigated by 1H NMR. As a consequence, highly selective, fast and sensitive fluorescence sensing is developed, which has a linear response range of 0.1–50.0 μM and a low detection limit of 0.075 μM (S/N = 3) for SC. This method is also used to detect SC in carbonate beverage practical samples. This strategy might have potential applications for the determination of the abuse of food additives and provide a way to guard serious food security issues.