Fluorimetric detection of Sn2 + ion in aqueous medium using Salicylaldehyde based nanoparticles and application to natural samples analysis

• Schiff base centered nano probe for selective detection of Sn2 + in aqueous solution
• Fluorescence enhancement due to excited state complexation between nanoparticles and Sn2 +
• Extremely lower Limit of Detection (0.0027 μg/mL)
• Successfully develop fluorimetric method for quantitative detection of Sn2 + from environmental samples
• Simple, quick, sensitive and selective method for Sn2 + detection in aqueous solution as compared with traditional methods

The fluorescent 2-[(E)-(2-phenylhydrazinylidene)methyl]phenol nanoparticles (PHPNPs) were prepared by a simple reprecipitation method. The prepared PHPNPs examined by Dynamic Light Scattering show narrower particle size distribution having an average particle size of 93.3 nm. The Scanning Electron Microphotograph shows distinct spherical shaped morphology of nanoparticles. The blue shift in UV-absorption and fluorescence spectra of PHPNPs with respect to corresponding spectra of PHP in acetone solution indicates H- aggregates and Aggregation Induced Enhanced Emission (AIEE) for nanoparticles. The nanoparticles show selective tendency towards the recognition of Sn2 + ions by enhancing the fluorescence intensity preference to Cu2 +, Fe3 +, Fe2 +, Ni2 +, NH4+, Ca2 +, Pb2 +, Hg2 + and Zn2 + ions, which actually seem to quench the fluorescence of nanoparticles. The studies on Langmuir adsorption plot, fluorescence lifetime of PHPNPs, DLS-Zeta sizer, UV–visible and fluorescence titration with and without Sn2 + helped to propose a suitable mechanism of fluorescence enhancement of nanoparticles by Sn2 + and their binding ability during complexation. The fluorescence enhancement effect of PHPNPs induced by Sn2 + is further used to develop an analytical method for detection of Sn2 + from aqueous medium in environmental samples.

Graphical AbstractThe simple Schiff base was synthesized and its nanoparticles are explored as novel probe to detect Sn2 + in aqueous medium via excited state complexation based on bathochromic shift with fluorescence enhancement.Figure optionsDownload as PowerPoint slide