Abstract:
:Although advances in microfluidic technology have enabled increasingly sophisticated biosensing and bioassay operations to be performed at the microscale, many of these applications employ such small amounts of charged biomolecules (DNA, proteins, and peptides) that they must first be preconcentrated to a detectable level. Efficient strategies for precisely handling minute quantities of biomolecules in microchannel geometries are critically needed; however, it has proven challenging to achieve simultaneous concentration, focusing, and metering capabilities with current-generation sample-injection technology. By using microfluidic chips incorporating arrays of individually addressable microfabricated electrodes, we demonstrate that DNA can be sequentially concentrated, focused into a narrow zone, metered, and injected into an analysis channel. This technique transports charged biomolecules between active electrodes upon application of a small potential difference (1 V) and is capable of achieving orders of magnitude concentration increases within a small device footprint. The collected samples are highly focused, with sample zone size and shape defined solely by electrode geometry.
journal_name
Proc Natl Acad Sci U S Aauthors
Shaikh FA,Ugaz VMdoi
10.1073/pnas.0506848103keywords:
subject
Has Abstractpub_date
2006-03-28 00:00:00pages
4825-30issue
13eissn
0027-8424issn
1091-6490pii
0506848103journal_volume
103pub_type
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