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

Abstract

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.