N-(1-Naphthly)ethylenediammonium cations (NEDA2+) stabilized silver nanoparticles (NEDA-Ag-NPs) were synthesized and explored their potential use for a chemo-sensor probe. The NEDA2+ cations being fluorescent active make the particles functionalized as well. They physically adsorb (adsorption constant (Kads), 2.65×109M−1) onto the surface of Ag-NPs and make them cationic with zeta potential value of 23±2mV. TEM image shows that particles are indeed spherical in shape. Monitoring SPR band (extinction coefficient (ε), 5.3×108M−1cm−1) the potencies of particles for sensing pH and citrate anions have been explored. The citrate anions interact with the surface adsorbed NEDA2+ cations and form association complex, NEDA2+‐‐‐citrate3‐, leading aggregation which is a kinetic effect. The aggregation kinetics was thus monitored for evaluating the association constant (Kasso) by studying UV–vis and fluorescence spectroscopic tools. The critical coagulation concentrations (CCC) for both the methods are considered to be the detection limit for citrate anions.