Clonazepam-responsive fluorometric probe based on chitosan functionalized silver nanoclusters for its quantification in exhaled breath condensate

Clonazepam is a high-potency, long-acting benzodiazepine that enhances GABA-A receptor activity. It is approved for short-term management of panic disorder, epilepsy, and nonconvulsive status epilepticus, and is also used off-label for conditions such as restless leg syndrome, acute mania, insomnia, and tardive dyskinesia. Due to its slow elimination and narrow therapeutic range, accurate analytical methods are essential for therapeutic monitoring. In this study, chitosan-functionalized silver nanoclusters were synthesized using a non-solvent-aided counter ion complexation method and used for detection and quantification of clonazepam in exhaled breath condensate (EBC) samples. After univariate optimization and validation based on ICH guidelines, the proposed method was applied to clonazepam analysis in the EBC samples obtained from patients undergoing clonazepam therapy.