Two emissive cellulose hydrogels for detection of nitrite using terbium luminescence

Here two novel terbium silica xerogels (H a and H b ) were assembled into cellulose hydrogels and two transparent films with narrow emission were successfully fabricated as fluorescent probes . We have found that the nitrite addition entailed efficient quenching effects of the photoluminescence intensity, contrasting the stable emissions upon exposure to other comparative ions (SO 4 2− , CO 3 2− , ClO 3 − , NO 3 − , AcO − , OH − , F − , Cl − , Br − , I − , K + , Na + , Fe 2+ , Mn 2+ , Pd 2+ , Cd 2+ , Co 2+ , Cu 2+ and Fe 3+ ). The recognition process may be ascribed to the coordination interaction between terbium ions and NO 2 − . Linear functions for spectroscopic titrations were obtained in both hydrogel-based films and the new soft sensors exhibit a dynamic range for determination of nitrite from 1   ×   10 −5 to 1   ×   10 −4   M.