An off-the-shelf supramolecular sensing system was designed to discriminate biologically relevant phosphates in neutral water using multivariate data analysis. The system is based on an indicator displacement assay comprising only two unmodified commercially available components: a dendritic poly-electrolyte and a common fluorescent dye. Effective discrimination of nucleotide diphosphates and inorganic diphosphate was achieved through principal component analysis (PCA).