A novel boronic acid-based fluorescence turn on sensor for specific detection of adenosine in urine

Three simple fluorescence turn-on sensors have been designed for the selective detection of adenosine (AD) based on a boronic acid receptor and a coumarin fluorophore (NLC, NJC, NDC). In the absence of AD, the fluorescence emission intensity of the sensors was relatively weak due to the effective electronic transfer from the to the coumarin to the boronic acid moiety. When the AD was introduced into the system, an obvious fluorescence enhancement was observed. It was attributed to the boronic acid covalently binding to the cis-diol unit of the AD resulting in the electronic transfer process being inhibited. Under the optimal conditions, these fluorescent sensors not only could perform good selectivity and fast response (< 30 s), but also show good water solubility. Finally, the proposed sensor NLC has been utilized for the AD determination in urine without any complicated pretreatment and the recovery was in the range of 95-103%. As a result, it is promising for application on the AD detection in complex biological samples. Moreover, there are no small molecular sensors detecting AD have been reported, yet, it is promising for providing a new platform to detect AD by small molecular sensor.

Automated summary

Three simple fluorescence turn-on sensors based on a boronic acid receptor and a coumarin fluorophore have been designed for the selective detection of adenosine. When adenosine is present, the sensors exhibit a significant fluorescence enhancement. These sensors demonstrate good selectivity, fast response, and water solubility, with the NLC sensor showing promising results for adenosine detection in urine samples.