A rapid fluorescence detecting platform: Applicable to sense carnitine and chloramphenicol in food samples

A new coenzyme A (CoA) fluorescence platform has been described for the sensitive determination of CoA, carnitine and chloramphenicol. Previously, our research group reported a long-wavelength latent florescent probe, termed "BCC". Here, we extend the application of BCC as an off-on fluorescence ratiometric indicator for the detection of acetyl CoA with a linear range of 0.5-10 μM and limit of detection (LOD) of 0.18 μM. We established a novel platform for the determination of carnitine and chloramphenicol in the presence of acetyl-CoA and their corresponding acetyl-CoA-transferring enzymes (chloramphenicol acetyltransferase (CAT) and carnitine acetyltransferase (CrAT), respectively). The proposed method detects carnitine and chloramphenicol in the linear range of 0.5-10 μM. The LODs for the determination of carnitine and chloramphenicol were found to be 0.5 μM and 0.3 μM, respectively. Moreover, BCC provides a facile assay platform for real-time monitoring of CAT and CrAT enzymatic activity in the presence of their corresponding substrates and acetyl-CoA. Practical feasibility of the proposed method has been demonstrated in food samples such as milk, powdered milk and honey, and the observed appreciable recoveries revealed its promising practicality.