Utilizing copper-doped graphene quantum dots as a fluorescent sensor for determination of carbamazepine in exhaled...

Carbamazepine is a versatile pharmaceutical used mainly for epilepsy and mood stabilization, but like all medications, it requires careful monitoring due to its potential side effects and interactions. In the current work, a fluorescent nanosensor was developed for the carbamazepine determination in the exhaled breath condensate (EBC). The nanosensor consists of graphene quantum dots doped with copper (Cu-doped GQDs). The presence of carbamazepine significantly decreased the fluorescence of Cu-doped GQDs, resulting in a quenching effect within a concentration range of 0.02-2.0 µg/mL, which occurs due to dynamic, rather than static, quenching according to Stern-Volmer plot. The relative standard deviations for intra-day and inter-day analysis of carbamazepine were 1.8 % and 4.8 %, respectively. The validated sensor was effectively employed for carbamazepine analysis in EBC of patients receiving the drug.