There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
Currently, the use of electrical readout methods for the investigation of microtissue
spheroids in combination with lab automation tools is hindered by the cable connections
that are required to interrogate the on-chip-integrated electrodes. To overcome this
limitation, we developed a wireless sensor scheme, which can detect the size variation
of microtissues during long-term culturing and drug exposure assays. The sensor system
includes an interrogation board, which is composed by an inductor-capacitor (LC) readout
circuit, and the tissue culture platform with integrated split-ring sensors. The magnetic
coupling between the LC circuit and the sensors enables the interrogation of the on-chip
sensors without any wire connection to the culture platform. By optimizing the sensor
dimensions and the LC resonance frequencies, we were able to avoid cross talk between
neighboring sensors. We integrated 12 tissue compartments on a standard microscopy
slide with a sensor-to-sensor pitch of 9 mm, which is in accordance with standard
96 well-plate dimensions. As proof-of-concept experiment for the developed system,
we monitored continuously and during more than four days the growth inhibition of
colon-cancer microtissue spheroids that had been exposed to different concentration
of doxorubicin, a chemotherapeutic compound. The stability of the measurements during
long-term culturing and the compatibility of the sensor scheme with standard lab equipment
offers great potential for automated electrical microtissue spheroid characterization.