Chalcogenides-based Tubular Micromotors in Fluorescent Assays.

WS/Pt and MoS/Pt bubble propelled micromotors are used as "on-the-fly" sensing platforms in bioassays, using a highly selective affinity peptide probe for "OFF-ON" detection of as a model endotoxin. The different outer micromotor surface characteristics play an important role in the sensing performance. The relatively high outer surface of WS/Pt micromotors results in a 3.5-fold increase in sensitivity compared to MoS/Pt micromotors due to enhanced peptide probe loading and release. The peptide-modified WS micromotors are used as a low-cost and high-throughput approach for the determination of endotoxin after only 60 s, with a limit of detection of 1.9 ng mL and high selectivity. The method has been validated using spiked samples (tap water, blood serum, and saliva) and bacteria media (blank broth, , and ). The concept can be extended to the analysis of other (bio)-analytes and easily incorporated into portable instrumentation, holding great promise in a myriad of clinical, environmental, or food-safety applications.