Remote Sensing of Cell-Culture Assays

Abstract

This chapter describes a full system developed to perform the remote sensing of cellculture experiments from any access point with internet connection. The proposed system allows the real-time monitoring of cell assays thanks to bioimpedance measurement circuits developed to count the number of cell present in a culture. Cell-culture characterization is performed through the measurement of the increasing bioimpedance parameter over time. The circuit implementation is based on the oscillation-based test (OBT) methodology. Bioimpedance of cell cultures is measured in terms of the oscillation parameters (frequency, amplitude, phase, etc.) and used as empirical markers to carry out an appropriate interpretation in terms of cell size identiication, cell counting, cell growth, growth rhythm, etc. The device is capable of managing the whole sensing task and performs wireless communication through a Bluetooth module. Data are interpreted and displayed on a computer or a mobile phone through a web application. The system has its practical application in drug development processes, ofering a label-free, high-throughput, and high-content screening method for cellular research, avoiding the classical end-point techniques and a signiicant workload and cost material reduction.

An Empirical-Mathematical Approach for Calibration and Fitting Cell-Electrode Electrical Models in Bioimpedance Tests

“…In this work, Matlab software has been used to simulate the calibration protocol, and for the testing and validation of the model in real time. The next step is to implement the Matlab script in the smart prototype of our OBT system approach [ 15 , 16 , 17 , 18 ]. The OBT prototype will then be able to autonomously follow the ff and the cell density in real time.…”

“…A mathematical description of the full system was required for cell-electrode electrical model estimation. The circuit system described in Figure 3 [ 15 , 16 , 17 , 18 ] has three main circuit blocks; a band-pass filter ( H BP ), a current source ( I Zc ), and a voltage comparator block ( K -gain amplifier, comparator filter – H CMP,F –, and the voltage discriminator).…”

“… The BioZ equations: where is the transfer function of the cell-electrode electrical model and the other parameters are defined by the resistances and the capacitors of the electric model ( , , , , and ), as can be seen on Equations (7)–(11). The OBT equations (see Figure 3 and [ 15 , 16 ]): …”

“…In this work, the measurement method is the oscillation-based test (OBT), detailed in [ 15 , 16 , 17 , 18 ]. This technique is based on connecting the BioZ as an oscillator.…”

“…In summary, it is proposed to perform, first, a calibration procedure by employing the OBT technique [ 15 , 16 , 17 , 18 ], and second, to validate with this same technique, the results for other assays with different cells densities. Thus, different initial number of cells was seeded to validate the model obtained in the calibration step.…”