Modeling of cellular pearl chain formation using a double photoconductive layer biochip

• A double photoconductive layers biochip focusing biological cells and forming specific pearl chains was studied.
• It was composed of two photoconductive layers coated on the bottom and top of ITO-based glass.
• The oscillating spatial electric field was employed to induce the motion of polarizable neutral particles.

A typical double photoconductive layer biochip focusing biological cells and forming specific pearl chains has been studied theoretically in this paper. It was composed of two photoconductive layers coated on the bottom and top of ITO-based glass. A light pattern was used to create face-to-face virtual electrodes and the resulting oscillatory spatial electric field was employed to induce the motion of polarizable neutral particles. In order to estimate the behaviors of the suspended particles, a numerical model including dielectrophoretic forces, dipole–dipole forces and other forces, was implemented by means of the Monte Carlo method. The results indicated that steady-state chains could be formed in a uniform electric field owing to the dipole moment effect. In a non-uniform electric field created by the use of a light pattern, the positive DEP force created a more focused pattern of chains. The work concerning the numerical simulation indicated that this chip could form fixed-length particle chains in perpendicular alignment to satisfy the structured assembly of tissues in the histological engineering application.