Ratiometric fluorescence and visual determination of tetracycline antibiotics based on Y and copper nanoclusters-induced cascade signal amplification.

A ratiometric fluorescence probe is proposed for sensitive and visual detection of tetracyclinee (TC) based on cascade fluorescence signal amplification induced by bovine serum albumin-stabilized copper nanoclusters (BSA-CuNCs) and yttrium ions (Y). TC can combine with Y to form the complex (TC-Y) to enhance the fluorescence of TC at 515 nm. Then, positively charged TC-Y and negatively charged BSA-CuNCs was bonded together by electrostatic interactions to achieve the fluorescence resonance energy transfer (FRET) process.