Monthly Meeting

Technical Program

“High Throughput LC and MS Using Droplet Microfluidics”

Manipulating samples as droplets within microfluidic devices has emerged as an interesting approach for chemical analysis and screening. In segmented flow, one embodiment of this technology, nanoliter samples are manipulated in microfluidic channels as plugs separated by an immiscible fluid, such as air or fluorinated oil. These plugs serve as miniature test-tubes in which reactions can be performed at high throughput. Microfluidic tools have been developed to split, dilute, extract, and filter such plugs at rates >1000 samples/s. Most experiments have been limited to fluorescence detection, but we have developed methods to analyze droplet content by mass spectrometry (MS), chromatography, and ion mobility spectrometry. A natural application of this technology is for high throughput experimentation. One area where we have applied this technology is for catalyst discovery. Biocatalysts can be developed by screening enzyme variants to identify active enzymes for a given reaction. Similarly, traditional organic catalysts require extensive exploration of reaction conditions and substrates to develop. We have developed droplet based approaches that has the potential to decrease the time required to develop such catalysts using droplet-MS. Droplet technology can also be used for chemical monitoring or sensing applications. In this approach samples emerging from a miniaturized sampling device are segmented for later analysis. We have used this method to monitor neurotransmitter dynamics in the brain. The technology and application to studies of neurotransmission will be demonstrated.