Ratiometric fluorescent sensor for shutter-speedy and ultra-sensitive monitoring of antibiotic utilizing multiple fluorescent devices

Sensitive and rapid sensing is extremely vital to in-situ monitor trace chemicals, herein, multiple visual devices have been developed to ultra-sensitively screen antibiotic oxytetracyline (OTC) with shutter-speed. The calcium ion fixed on the nanoprobe sensitively and rapidly coordinates to the hydroxyl group of OTC due to its special electronic orbital structure, resulting in evolutive visual distinct color change from red to bright green within a shutter pressing (<0.1 s) upon adding OTC, and consequently demonstrating visible and dosage-sensitive detection with the detection limit down to 6.83 nM. Particularly, multiple fluorescent ratiometric devices based the designed nanoprobe applied in water, urine and pork samples have proved the practicability and accuracy of this method. This fast, sensitive, and visible sensing strategy holds great promise for wide applications, as well as the practical utilization value of multiple in-situ detection devices.