A novel platform for sensing an amino acid by integrating hydrogel photonic crystals with ternary complexes

A novel sensing platform based on the integration of hydrogel photonic crystals and ternary tetracycline-copper(II)-amino acid complexes has been proposed. Obvious and gradual diffraction wavelength shifts and color changes can be easily monitored during the stepwise coordination reaction process. This new strategy allows label-free detection and reversible sensing of glycine with high sensitivity.