(a) Receptor library, 3x, used in the discrimination of tachykinins and their analogues. (b) PCA score plot of response from α-neurokinin (HKTDSFVGLM-NH2) (blue), substance P (RPKPQQFFGLM-NH2) (light blue), and tachykinin analogues HKT (red), HKTD (green), and HET (violet). (c) Receptor library employed in the pattern based discriminaton of phosphorylated peptides. (d) Peptides and their phosphorylated versions analyzed. (e) LDA plots of the response of the analytes in b. (f) Structure of 5.