Microarray of non-connected gold pads used as high density electric traps for parallelized pairing and fusion of cells

Abstract

Cell fusion consists of inducing the formation of a hybridoma cell containing the genetic properties of the progenitor cells. Such an operation is usually performed chemically or electrically. The latter method, named electrofusion, is considered as having a strong potential, due to its efficiency and non-toxicity, but deserves further investigations prior to being applicable for key applications like antibody production and cancer immunotherapy. Indeed, to envision such applications, a high amount of hybrid cells is needed. In this context, we present in this paper a device for massive cell pairing and electrofusion, using a microarray of nonconnected conductive pads. The electrofusion chamber--or channel--exposes cells to an inhomogeneous electric field, caused by the pads array, enabling the trapping and pairing of cells with dielectrophoresis (DEP) forces prior to electrofusion. Compared to a mechanical trapping, such electric trapping is fully reversible (on/ off handling). The DEP force is contactless and thus eases the release of the produced hybridoma. Moreover, the absence of wire connections on the pads permits the high density trapping and electrofusion of cells. In this paper, the electric field mapping, the effect of metallic pads thickness, and the transmembrane potential of cells are studied based on a numerical model to optimize the device. Electric calculations and experiments were conducted to evaluate the trapping force. The structure was finally validated for cell pairing and electrofusion of arrays of cells. We believe that our approach of fully electric trapping with a simple structure is a promising method for massive production of electrofused hybridoma. V C 2013 AIP Publishing LLC. [http://dx

Defining Cell Cluster Size by Dielectrophoretic Capture at an Array of Wireless Electrodes of Several Distinct Lengths

“…Austin and coworkers previously described pDEP of DNA at an array of floating conductors of uniform size and shape—a technique which they called ‘electrodeless DEP’ [41]. Further, Hamdi et al reported nDEP capture and fusion (by electric pulse) of pairs of cells at a uniform array of non-connected gold pads [42]. In the current study, cells were captured using DEP on a wireless BPE array that incorporated a range of electrode lengths (top and side views, Scheme 1a,b).…”

Low Temperature Irreversible Poly(DiMethyl) Siloxane Packaging of Silanized SU8 Microchannels: Characterization and Lab-on-Chip Application

“…The presented bonding process had been used for the packaging of a microfluidic biodevice integrating electrodes for cell trapping by dielectrophoresis [35]. In this case, in order to guarantee the precise alignment of the microfluidic channels with the electric level, SU8 is spin-coated and exposed through a photolithography mask to define the microfluidic network according to electrodes position.…”

Manipulation and Optical Detection of Colloidal Functional Plasmonic Nanostructures in Microfluidic Systems

“…In the case of charged particles, electrophoresis causes the particles to follow the electric field lines in relation with its electric charge. However, for polarizable neutral particles submitted to an electric field, dielectrophoresis (DEP) is widely used [75], [76]. DEP offers trapping, focusing and separation capabilities [77].…”