BSA stabilised AuNCs as a 'Turn-Off' fluorescent probe for the sensing of propofol

The abuse of anaesthetic agent propofol is an increasing challenge in worldwide, therefore it is essential to develop simple and accurate methods for its detection. In the present study, a simple turn-off fluorescent sensing platform for the detection of propofol based on bovine serum albumin (BSA) stabilized gold nanoclusters (AuNCs) was developed. The fluorescent BSA-AuNCs were successfully prepared via previously reported microwave assisted method. The prepared red emitting BSA-AuNCs shows emission maximum at 685nm on excitation at 500nm. The fluorescence of the probe was quenched remarkably by the addition of propofol, due to electron transfer mechanism. The limit of detection (LoD) of propofol was found to be 0.12 mu M. This detection method has good selectivity towards propofol over other co-existing biomolecules and neurotransmitters. Moreover, this method was also utilized for the analysis of propofol spiked real samples (both blood serum & urine) and good recovery percentages were found. A paper strip assay was also successfully conducted for practical application.