Synthesis of cinacalcet containing acrylamide hydrogels by photopolymerization and studying their sensing properties

Novel cinacalcet containing acrylamide hydrogel (CIN-gel) was fabricated by free radical photopolymerization of acrylamide/N,N’-methylenebisacrylamide with cinacalcet hydrochloride as a photoinitiator. This hydrogel prepared by a one-pot photo-induced polymerization system was characterized with respect to its morphological and fluorescence features by means of SEM, UV–vis, and fluorescence spectroscopy. The CIN-gel displayed dual fluorescence emission when excited at 250 nm in water:acetonitrile (1:1, w/w) solution system owing to twisted intramolecular charge transfer between naphthalene and dimethylamino units in the cinacalcet moiety. The prepared fluorophore containing CIN-gel was employed as a fluorescent probe towards certain specific heavy metal ions (HMIs) such as Pb²⁺, Sn²⁺, Zn²⁺ and nitroaromatic compounds (NACs) such as 2-nitrotoluene, 2,4-dinitrophenol, 1,2-dinitrobenzene, 2,4,6-trinitrotoluene, 2,4,6-trinitrophenol, 4-nitrophenol, and 2,4-dinitrophenol. The use of cinacalcet hydrochloride as a photoinitiator and analyte for measuring HMIs and NACs during the production of the hydrogel is being reported for the first time. Fluorescence intensity of CIN-gel was gradually reduced upon the addition of NACs and HMIs. For all compounds, the highest quenching efficiencies were attained in the presence of Zn²⁺ (35.93%), 2,4,6-trinitrotoluene (95.67%), and 2,4-dinitrophenol (94.96%). Because of its simplicity and sensitivity, the proposed CIN-gel can be considered as potential chemical probe to detect the HMIs ions and NACs compounds.

Graphical abstract