The fabrication of triple-emission ratiometric fluorescent probe for on-site intelligent monitoring of tetracycline based on B/RCDs@ZIF-8.

Abstract

The sensitive and portable monitoring of tetracycline (TC) is significant for ensuring human and food safety. Herein, a triple-emission ratiometric fluorescent probe of B/RCDs@ZIF-8 was constructed by integrating blue and red fluorescence emission carbon dots (CDs) with ZIF-8 through a one-pot physical mixing method. TC induced the blue fluorescence emission quenched through internal filtering effect and the green fluorescence enhanced via the interaction between TC and ZIF-8, while the red fluorescence remains stable, thereby forming a ratiometric sensor for TC detection with a visual color transition and a lower detection limit of 18.6 nM. Additionally, smartphone-assisted sensor was fabricated for on-site visual detection of TC and satisfactory results were obtained in actual samples analysis, verifying its accuracy and reliability in practical applications. This work not only provided an efficient method for TC detection, but also offered guidance for the design of portable multifunctional nano-sensors toward convenient daily applications.