Selective recognition of lithium(I) ions using Biginelli based fluorescent organic nanoparticles in an aqueous medium

This study presents the fabrication of a Biginelli compound 1 into fluorescent organic nanoparticles (ONP) using a reprecipitation method. The fabricated ONP were characterized by TEM and DLS. Further, the ONP were found to be selective towards Li(I) ions with a fluorescence turn-on mechanism and exhibited no significant response to possibly interfering cations (Na+, K+, Mg2+ and Ca2+) in a competitive experiment. The limit of detection was calculated to be 122 nM. It is apparent from the pH titration that the current sensor is independent of any variation in pH. To get a better insight of spacial arrangement, the crystal structure of 1 was solved by X-ray crystallography. The progress in sensing of lithium ions by various types of sensors on different instruments has also been discussed briefly.