Bioelectric profiling of Rickettsia montanensis in Vero cells utilizing dielectrophoresis

Rickettsia is an intracellular bacteria transmitted to humans through ticks, lice, fleas, or their feces, causing acute symptoms such as fever, headache, rashes, and muscle aches. Detecting rickettsial diseases is challenging due to limitations in current methods such as negative results, low sensitivity, and high cost. These limitations highlight the need for improved detection methods. Dielectrophoresis (DEP) offers a promising alternative to develop a point-of-care economical, label-free, and sensitive diagnostic tool. By exposing cells to non-uniform electric fields one can measure the electrical properties of the cells which are different and unique based on the cell type. By comparing the dielectric profiles of healthy and infected cells, DEP could be utilized to design a rapid, cost-effective diagnostic tool. Initial steps involve characterizing the electrophysiological properties of Vero cells infected with Rickettsia montanensis to develop this new detection tool. This study found significant differences in electrical parameters between healthy and Rickettsia spp. infected Vero cells, particularly at a medium conductivity of 500 µS/cm. Moreover, we found that the dielectric spectrum showed the greatest differences between healthy and Rickettsia spp. infected Vero cells at medium conductivity of 500 µS/cm, with significantly different dielectrophoretic crossover frequencies (no DEP force region). These findings suggest that dielectrophoretic detection of infected cells could serve as a quick, cost-effective, label-free, and sensitive alternative for developing a point-of-care diagnostic tool for Rickettsial infections.