Engineering binding tetracycline with CDs/QDs@MOFs nanoarchitecture for ternary fluorescence-based point-of-care testing

Abstract

The substantial risk to human health posed by tetracycline (TC) residues necessitates the development of a facile and portable sensor for rapid and selective detection. In the present study, an ingeniously integrated "turn-on" and "turn-off" ternary emissive ratio sensing platform was manufactured for TC point-of-care testing by engineering the bond of TC with zeolitic imidazolate framework-8 (ZIF-8) in the carbon dots/quantum dots embedded ZIF-8 nanoarchitecture (CDs/QDs@ZIF-8). By integrated blue-fluorescent CDs and red-fluorescent QDs into ZIF-8, a multiple-emission fluorescence responsive probe was constructed. By integrating the combination of TC and ZIF-8, as well as the response of CDs to TC, this base realized the ternary emissive ratio sensing of TC with the variation of blue-green-red fluorescence signals with a detection range of 0.5–50.0 μM and a limit of detection (LOD) as low as 14.2 nM. Additionally, a portable test kit was developed for on-site TC monitoring based on nano-probe-immobilized hydrogel with the aid of a custom 3D-printed, smartphone-based portable device. This work integrated "turn-on" and "turn-off" multi-color sensing strategy, combined with the use of hydrogels and smartphone technology, is anticipated to spark new inspiration for developing a new generation of multi-emission TCs sensors for biomedical monitoring.