Lab-on-a-chip particles manipulation for point-of-care diagnostic systems utilizing dielectrophoresis

Particle manipulation has attracted the attention of many researchers around the globe for various biomedical applications. Although several methods have been utilized to sort particles on lab-on-a-chip platforms, dielectrophoresis (DEP) possess exclusive advantages over other methods. In this paper, we investigated microarray dot electrodes to manipulate microparticles. The geometry of the dot electrode enjoys unique benefits compared to other geometries, including enclosed areas of analysis and strong electric field with axisymmetrical distribution. DEP experiments were conducted to manipulate 1 μm polystyrene particles using the developed DEP system. Results showed that the response of the microparticle populations can be controlled by merely adjusting the applied frequency to induce either positive or negative DEP effects. In negative DEP case, microparticles were gathered at the dot center, while microparticles were collected at the dot edge in the case of positive DEP. Such microarray dot platforms can be utilized to develop economical point-of-care (POC) diagnostic systems by analyzing the transmitted light variations inside the dot regions.