| Advances in photolithography and microelectronic fabrication techniques have introduced new possibilities for automated, high throughput biomedical investigations and analysis. The ability to fabricate electrode patterns with dimensions down to a single micron affords control applications at the scale of biology. Devices that incorporate micro-fluidics, micro-electrodes and photodetectors can now be inexpensively mass-produced for fully automated applications seamlessly integrated with programmable electronics. However, energy requirements and reliable means of biomolecular separation are still obstacles to realizing more sophisticated micro total analysis systems (muTAS). This work examines two electrically mediated functionalities, electroporation and dielectrophoresis (DEP) which can be integral to bioanalytical processing steps. Electroporation uses high voltage pulsed electric fields to create pores in the membrane of a biological cell to release its cellular contents. This work demonstrates an effective strategy to achieve a 4-fold reduction in electroporation voltage through the use of field enhancing nano-materials. Whereas DEP is an electrically mediated effect which polarizes particles (microbeads, cells, viruses, DNA, proteins etc.) in suspension and causes their translational movement. Novel electrode patterns and multi-phase activation sequences are used to demonstrate predictable particle manipulation capabilities necessary for more complex multi-step bioanalytical tasks. The research presented here investigates novel design applications of nanostructures and micro-photolithographically patterned electrode features to create enhanced lab-on-a-chip or muTAS automated diagnostic applications. |
