Inosine-5-monophosphate coordination complex as a unique fluorescence detector for the amino-acids

The role of selective determination of the amino acids has remained a big challenge in the field of diagnostics for certain cancer cell lines. Conventional approaches for the selective and sensitive analysis, and detection of the amino acids require cost ineffective techniques like MS (mass spectrometry) and PCR (Polymerase Chain Reactions). In the current study, the selective determination of two aromatic amino acids Trp (Tryptophan) and Tyr (Tyrosine) by a Co(II) inosine-5′-monophospate coordination complex (C-1) was evaluated. Both amino acids are important biomarkers in gastroesophageal cancers and triple negative breast cancer. The assessment of the structure of complex was done by XRD (X-Ray Diffraction), while the phase determination and chirality were determined by PXRD (Powder X-Ray Diffraction) and CD (Circular Dichroism). Among the 20 natural amino acids, selective behavior of C-1 towards l-Tryptophan (Trp) and l-Tyrosine (Tyr) have been observed; the determination of selective binding was determined by both fluorescence and UV-visible spectrographs. Molecular simulations and molecular dynamics highlighted a significant affinity for l-Trp and l-Tyr, which is mediated by metal-ligand coordination and π-π stacking interaction. An important finding was that spontaneous binding was indicated by the shift in Gibbs free energy. The binding constants (k_b) for Trp and Tyr were found to be 4.87 × 10³ M⁻¹ and 6.00 × 10⁴ M⁻¹, respectively. The measured detection limits (LOD) for Trp and Tyr, were 0.09 and 0.32 µM, respectively. Notably, current research highlights a green and human friendly single crystal enabled wavelength-resolved quantitative detection of both Trp and Tyr, underscoring the dual-analyte sensing advantage of the present system.