TY - JOUR
T1 - Enhanced sub-micron colloidal particle separation with interdigitated microelectrode arrays using mixed AC/DC dielectrophoretic scheme
AU - Swaminathan, Vikhram V.
AU - Shannon, Mark A.
AU - Bashir, Rashid
N1 - The authors would like to thank Dr. Bruce Flachsbart for assistance in microfabrication, Dr. Glennys Mensing for assistance with microfluidics, and Dr. Bobby Reddy (Jr.) and Dr. Eric Salm for useful discussions. Microfabrication facilities were provided by the Micro-Nano Mechanical Systems Laboratory and Micro and Nanotechnology Laboratory at UIUC. This research was financially supported through the National Institutes of Health (R01CA20003) and the US Defense Advanced research Projects Agency (W911NF09C0079).
PY - 2015/4
Y1 - 2015/4
N2 - Dielectrophoretic separation of particles finds a variety of applications in the capture of species such as cells, viruses, proteins, DNA from biological systems, as well as other organic and inorganic contaminants from water. The ability to capture particles is constrained by poor volumetric scaling of separation force with respect to particle diameter, as well as the weak penetration of electric fields in the media. In order to improve the separation of sub-micron colloids, we present a scheme based on multiple interdigitated electrode arrays under mixed AC/DC bias. The use of high frequency longitudinal AC bias breaks the shielding effects through electroosmotic micromixing to enhance electric fields through the electrolyte, while a transverse DC bias between the electrode arrays enables penetration of the separation force to capture particles from the bulk of the microchannel. We determine the favorable biasing conditions for field enhancement with the help of analytical models, and experimentally demonstrate the improved capture from sub-micron colloidal suspensions with the mixed AC/DC electrostatic excitation scheme over conventional AC-DEP methods.
AB - Dielectrophoretic separation of particles finds a variety of applications in the capture of species such as cells, viruses, proteins, DNA from biological systems, as well as other organic and inorganic contaminants from water. The ability to capture particles is constrained by poor volumetric scaling of separation force with respect to particle diameter, as well as the weak penetration of electric fields in the media. In order to improve the separation of sub-micron colloids, we present a scheme based on multiple interdigitated electrode arrays under mixed AC/DC bias. The use of high frequency longitudinal AC bias breaks the shielding effects through electroosmotic micromixing to enhance electric fields through the electrolyte, while a transverse DC bias between the electrode arrays enables penetration of the separation force to capture particles from the bulk of the microchannel. We determine the favorable biasing conditions for field enhancement with the help of analytical models, and experimentally demonstrate the improved capture from sub-micron colloidal suspensions with the mixed AC/DC electrostatic excitation scheme over conventional AC-DEP methods.
KW - Colloidal particle
KW - Dielectrophoresis
KW - Interdigitated electrodes
KW - Microfluidics
KW - Particle separation
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U2 - 10.1007/s10544-015-9935-z
DO - 10.1007/s10544-015-9935-z
M3 - Article
C2 - 25681047
AN - SCOPUS:84923280355
SN - 1387-2176
VL - 17
JO - Biomedical microdevices
JF - Biomedical microdevices
IS - 2
ER -