Design and response analysis of a circular patch resonator for adherent cell culture detection

The study of the interaction between electromagnetic waves and matter plays a crucial role in detecting materials under test (MUTs). Recently, radiofrequency (RF) planar resonator probes have been used to characterize MUTs by evaluating their dielectric properties. Many studies proposed these devices as biosensors, especially for dielectric measurement of living cellular suspension or even single cell. However, even though these cellular applications represent a starting point for medical diagnostic improvement, they do not consider cell interaction and adhesion. We proposed a preliminary study to design a circular patch resonator to detect adherent cell cultures in this work. Different configurations comprising a patch smaller, equal and greater than that of a standard culture Petri dish have been analyzed. The simulation results were then compared with the theoretical ones obtained applying the circular microstrip antenna's empirical equation. Results showed that the simulation outcomes differed from the theoretical ones less than 1.5%. Finally, once the best patch diameter was identified, two other simulation sets were carried out to evaluate the antenna's sensitivity. In the first set, we simulated the antenna response to four different volumes of culture medium (from 1.50 ml to 6.00 ml), while in the second one, we simulated the antenna response to different levels of C2C12 cell confluence in a fixed volume (1.5 ml) of culture medium. The results showed that the designed probe could discriminate between medium and C2C12 culture cells based on their permittivity change.