A pH-dependent fluorescent and colouring macrocycle for the high selective detection of arginine in pure water

Abstract In this work, a water-soluble fluorescent and colouring macrocycle deprotonated-calixpyridinium was obtained by a simple pH modulatory strategy. This type of fluorescent and colouring macrocyclic skeleton as host will be certainly applied in a large number of fields, especially in the sensing area. Herein, a near white-light emission was carried out by an innovative method of deprotonated-calixpyridinium-based host–guest interactions employing camptothecin sodium as the guest. Moreover, the pH-responsive luminescence color change of calixpyridinium–camptothecin sodium complex was further applied for the high selective detection of arginine in pure water and real samples, which is quite important in the accurate diagnosis of various disorders. The newfound pH-dependent luminescent and colouring properties of calixpyridinium will also provide an alternative idea for the development of other novel fluorescent and colorimetric macrocyclic sensors.