Enhancing Protease Activity Assay in Droplet-Based Microfluidics Using a Biomolecule Concentrator

Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 36-841, 77 Massachusetts Avenue, Cambridge Massachusetts 02139, USA.
Journal of the American Chemical Society (Impact Factor: 12.11). 06/2011; 133(27):10368-71. DOI: 10.1021/ja2036628
Source: PubMed


We introduce an integrated microfluidic device consisting of a biomolecule concentrator and a microdroplet generator, which enhances the limited sensitivity of low-abundance enzyme assays by concentrating biomolecules before encapsulating them into droplet microreactors. We used this platform to detect ultralow levels of matrix metalloproteinases (MMPs) from diluted cellular supernatant and showed that it significantly (~10-fold) reduced the time required to complete the assay and the sample volume used.

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