Online bioimpedance feedback for in vivo electroporated tissues

• Published in: Journal of physics. Conference series Vol. 224; no. 1; p. 012114
• Main Authors: Medrano, J, Rey, J I, Connolly, R J, Anderson, A, Jaroszeski, M, Gitlin, R
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.04.2010
• Subjects: Cell death; Cytoplasm; Electric fields; Electroporation; Feedback; Impedance; In vivo methods and tests; Membranes; New technology; Optimization; Permeability; Physics; Pulse amplitude
• ISSN: 1742-6596; 1742-6588; 1742-6596
• DOI: 10.1088/1742-6596/224/1/012114

Electroporation in vivo is a biotechnology method that uses short-duration high intensity electric fields to enhance plasma membrane permeability in living cells in order to facilitate the uptake of drugs, DNA, genes and proteins into the cytoplasm. The degree of permeability is related to the tissue's bioimpedance; hence, accurate impedance evaluation throughout electroporation treatment is essential to 1) avoid over-treating tissues resulting in excessive cell death and 2) under-treating tissues resulting in poor permeability. Cell viability and membrane permeability is based on a number of factors, including: time elapsed after electroporation, electroporation pulse amplitude, tissue type, and so on; thus, efficient feedback protocols must minimize delays between treatment and impedance readings. Current methods of bioimpedance feedback are often cumbersome and impedance analysis devices can be expensive, bulky, and immobile. Emerging technologies facilitate economical methods, fast protocols, and portability to realize bioimpedance measurement and feedback online (i.e. realtime). Consequently, this research uses automation software, logic-biased protocols, an inexpensive commercially available impedance analyzer microchip, and a custom-built hexagonal electrode probe to measure dynamic bioimpedance changes. This work demonstrates how this novel system measures tissue bioimpedance instantly and efficiently before and after electroporation. Additionally this system allows for the comparison of electrode geometries as well as electric field' magnitudes and distributions. Follow up work will pursue the optimization of plasma membrane permeability for several tissue/cell types.