Synthesis of 3,6-di(pyridin-2-yl)-1,2,4,5-tetrazine (pytz) capped silver nanoparticles using 3,6-di(pyridin-2-yl)-1,4-dihydro-1,2,4,5-tetrazine as reducing agent: Application in naked eye sensing of Cu2+, Ni2+ and Ag+ ions in aqueous solution and paper platform.

The synthesis of 3,6-di(pyridin-2-yl)-1,2,4,5-s-tetrazine(pytz) capped silver nanoparticles (AgNPs) is achieved by reacting an aqueous AgNO3 solution with 3,6-di(pyridin-2-yl)-1,4-dihydro-1,2,4,5-tetrazine in ethanol without using of any external reducing agent. Morphology and crystalline structure of the prepared silver nanoparticles were characterized by HRTEM and XRD techniques. The pytz capped AgNPs could be used to selective and sensitive detection of Cu2+, Ni2+ and Ag+ in aqueous solution. The sensor was rapid as the measurements were carried out within 3 min of addition of the test solution to the AgNPs-pytz hybrid (TzAgNPs). The present method has a detection limit of 17.5, 9.4 and 13.2 µM (for a signal/noise (S/N) ratio > 3) for Cu2+, Ni2+ and Ag+, respectively. Moreover, this AgNPs-pytz hybrid sensor is applied to test paper for the detection of Cu2+, Ni2+ and Ag+ with the naked eye. The test paper could be potentially used in the rapid detection of Cu2+, Ni2+ and Ag+ in real samples. [ABSTRACT FROM AUTHOR]