Enrichment of Aggregation-Induced Emission Aggregates Using Acoustic Streaming Tweezers in Microfluidics for Trace Human Serum Albumin Detection

Aggregation-dependent brightness (ADB) indirectly limits the in vitro performance of a pure aggregation-induced emission (AIE) probe in many ways; thus, controlling the aggregation state of the AIE probe is helpful for detecting an object of interest. Many studies are focused on the molecule design of the AIE probes, while less efforts have been made for the control of the aggregation of the AIEs. Here, an acoustic streaming tweezer (AST) generated using a gigahertz bulk acoustic wave resonator was applied to manipulate the aggregation status of the AIE probe and further enhance their performance for human serum albumin (HSA) detection. As the trapping size of the AST matches the working size of the AIE probe, the streaming can enrich and accumulate AIE nanoparticles, which then further trigger larger aggregates. Due to the ADB effect, the fluorescence intensity strongly increased, and thus, the detection limit of HSA was reduced to 0.5 mu g/mL, which is low enough for kidney disease detection. Such an AST-assisted ADB strategy is potentially applicable to other AIE probes and can work as a portable choice for the biomedical detection.

Automated summary

Aggregation-dependent brightness (ADB) indirectly limits the in vitro performance of a pure aggregation-induced emission (AIE) probe in many ways; thus, controlling the aggregation state of the AIE probe is helpful for detecting an object of interest. An acoustic streaming tweezer (AST) generated using a gigahertz bulk acoustic wave resonator was applied to manipulate the aggregation status of the AIE probe and enhance their performance for human serum albumin (HSA) detection. Due to the ADB effect, the fluorescence intensity strongly increased, and the detection limit of HSA was reduced to 0.5 μg/mL, making it suitable for kidney disease detection. Such an AST-assisted ADB strategy can be applied to other AIE probes and serve as a portable choice for biomedical detection.