PRESSURE DRIVEN MICROFLUIDIC INJECTION FOR CHEMICAL SEPARATIONS

摘要

Methods that allow independently applied pressures to a BGE reservoir and a sample reservoir for pressure-driven injection that can inject a discrete sample plug into a separation channel that does not require voltage applied to the sample reservoir and can allow for in-channel focusing methods to be used. The methods are particularly suitable for use with a mass spectrometer.

主权项

1. A method of sample processing, comprising:
providing a microfluidic device with at least one separation channel in fluid communication with a background electrolyte (BGE) reservoir, a waste reservoir having a waste channel that merges into the separation channel, and a sample reservoir having a sample channel that merges into the separation channel; injecting a fluid sample from the sample reservoir into the separation channel downstream of the BGE reservoir by concurrently applying defined pressures to the BGE reservoir and the sample reservoir; then clearing a trailing end of the sample from the sample channel and flowing fluid from the BGE reservoir to deliver a plug of the sample in the separation channel in response to reducing or removing the pressure applied to the sample reservoir while applying pressure to the BGE reservoir so that pressure applied to the BGE reservoir is greater than pressure then applied to the sample reservoir; and then electrophoretically separating the delivered sample in the separation channel by applying voltage to the microfluidic device.