TY  - JOUR
A1  - Laux, Eva-Maria
A1  - Ermilova, Elena
A1  - Pannwitz, Daniel
A1  - Gibbons, Jessica
A1  - Hölzel, Ralph
A1  - Bier, Frank Fabian
T1  - Dielectric Spectroscopy of Biomolecules up to 110 GHz
JF  - Frequenz
N2  - Radio-frequency fields in the GHz range are increasingly applied in biotechnology and medicine. In order to fully exploit both their potential and their risks detailed information about the dielectric properties of biological material is needed. For this purpose a measuring system is presented that allows the acquisition of complex dielectric spectra over 4 frequency decade up to 110 GHz. Routines for calibration and for data evaluation according to physicochemical interaction models have been developed. The frequency dependent permittivity and dielectric loss of some proteins and nucleic acids, the main classes of biomolecules, and of their sub-units have been determined. Dielectric spectra are presented for the amino acid alanine, the proteins lysozyme and haemoglobin, the nucleotides AMP and ATP, and for the plasmid pET-21, which has been produced by bacterial culture. Characterisation of a variety of biomolecules is envisaged, as is the application to studies on protein structure and function.
KW  - dielectric
KW  - spectroscopy
KW  - permittivity
KW  - protein
KW  - DNA
KW  - amino acid
KW  - plasmid
Y1  - 2018
U6  - https://doi.org/10.1515/freq-2018-0010
SN  - 0016-1136
SN  - 2191-6349
VL  - 72
IS  - 3-4
SP  - 135
EP  - 140
PB  - De Gruyter
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Laux, Eva-Maria
A1  - Bier, Frank Fabian
A1  - Hölzel, Ralph
T1  - Dielectrophoretic Stretching of DNA
JF  - DNA Nanotechnology
N2  - The spatial control of DNA and of self-assembled DNA constructs is a prerequisite for the preparation of DNA-based nanostructures and microstructures and a useful tool for studies on single DNA molecules. Here we describe a protocol for the accumulation of dissolved lambda-DNA molecules between planar microelectrodes by the action of inhomogeneous radiofrequency electric fields. The resulting AC electrokinetic forces stretch the DNA molecules and align them parallel to the electric field. The electrode preparation from off-the-shelf electronic components is explained, and a detailed description of the electronic setup is given. The experimental procedure is controlled in real-time by fluorescence microscopy.
KW  - Alignment
KW  - Dielectrophoresis
KW  - DNA
KW  - Electrokinetics
KW  - Interdigitated electrodes
KW  - Stretching
Y1  - 2018
SN  - 978-1-4939-8582-1
SN  - 978-1-4939-8581-4
U6  - https://doi.org/10.1007/978-1-4939-8582-1_14
SN  - 1064-3745
SN  - 1940-6029
SP  - 199
EP  - 208
PB  - Humana Press Inc.
CY  - New York
ET  - 2
ER  -