Abstract:
:Light-induced dielectrophoretic movement of polystyrene beads and lambda-DNA is studied using thin films of amorphous hydrogenated silicon as local photoaddressable electrodes with a diameter of 4 microm. Positive (high-field seeking) dielectrophoretic movement is observed for both types of objects. The absence of strong negative (low-field seeking) dielectrophoresis of DNA at high frequencies is in agreement with the similarity of the dielectric constants of DNA and water, the real part of the dielectric function. The corresponding imaginary part of the dielectric function governed by the conductivity of DNA can be determined from a comparison of the frequency dependence of the dielectrophoretic drift velocity with the Clausius-Mossotti relation.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Hoeb M,Rädler JO,Klein S,Stutzmann M,Brandt MSdoi
10.1529/biophysj.106.101188subject
Has Abstractpub_date
2007-08-01 00:00:00pages
1032-8issue
3eissn
0006-3495issn
1542-0086pii
S0006-3495(07)71359-0journal_volume
93pub_type
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