Dipodal Schiff's base based receptor (R1) was developed and characterized using H-1 NMR, C-13 NMR and mass spectroscopy and optimized its structure using DMol(3) package. In order to evaluate the sensor activity in aqueous medium, R1was processed into organic nanoparticles (N1) using re-precipitation method. The prepared N1were characterized using techniques like dynamic light scattering (DLS) and transmission electron microscopy (TEM). To portray N1 as sensor, it was screened with various anions and found to respond selectively for PO43- ions with detection limit of 8.6 nM having a regression coefficient of 0.98912. The proposed sensor was successfully tested for real time analysis of biologically important phosphate molecules, with accuracy more than 95%. (C) 2015 Elsevier Ltd. All rights reserved.