A novel “on–off–on” fluorescence assay for the discriminative detection of Cu(<scp>ii</scp>) and <scp>l-</scp>cysteine based on red-emissive Si-CDs and cellular imaging applications

Abstract

Copper ions (Cu²⁺) and <sc>l-</sc>cysteine (<sc>l-</sc>Cys) in the human body always play critical roles in various physiological processes, while abnormal Cu²⁺ and <sc>l-</sc>Cys concentrations in the biological system lead to many diseases.