End-point impedance analysis of HeLa cells using a novel impedance measuring system

IBST/CATIM

9 / 1 4 / 2 0 1 4

Rhys Alun Luckwell

Abstract

BACKGROUND & AIMS: The focus of this project is to build upon previous work on impedance analysis of biological systems. By comparing a novel UWE impedance system with a current impedance system already on the market the ultimate aim of this work is to put forth a system which can be used to monitor impedance of biological systems which largely uses using traditional tissue culture materials. In doing so, allowing the screening of assays for changes in cell metabolism in response to toxins without the need for expensive and specialised laboratory equipment.

Methods: IC50 of actinomycin D was measured using two end point assays, neutral red and XTT, and also in real time by using iCELLigence impedance measurement system. Impedance and phase of HeLa cells treated with actinomycin D were measured by using Cypher C-60/UWE impedance system and plotted using CypherGraph. Impedance analysis was also carried out by using the iCelligence system and analysis was done be plotting area under curve (AUC) against cell number.

RESULTS: The results from the Cypher C-60/UWE system suggest that as the number of dead HeLa cells increase through a greater dosage of actinomycin D the impedance increased and the phase decreased.

CONCLUSIONS: From the results of the Cypher-60/UWE system there seemed to be a difference in the impedance and phase between the cells treated with different actinomycin D concentration. However it was difficult to achieve constancy in these results and there was no obvious impedance ‘finger print’ displayed. The major drawback to the Cypher C-60/UWE impedance system is that it fails to screen a large number of assays at one time. For this system to develop further, an electrode plate has to be created which can read a traditional 12 or even a 24 well tissue culture plate without there being a gap between the plastic and the electrode.