Vacuum Casting to Manufacture a Plastic Biochip for Highly Parallel Cell Transfection

International audienceA novel polymer microarray fabrication technique is presented and applied to the realization of a biochip for highly parallelized cell transfection. The proposed microfabrication technique is derived from a macroscale rapid prototyping technique called vacuum casting. It was optimized to reduce production cost, in order to produce small series (100-10 000 chip series) of chips to meet demand in today's market of cellulomics. Microfabrication technologies and rapid prototyping technologies are combined to shape the master part, which can thus involve microsized features. The corresponding female structure is moulded in a flexible silicone material. The duplicated polymer chips are obtained by casting a thermosetting plastic under vacuum. The dimensional replication accuracy between the master part and the duplicated parts is uniform over the duplicated parts and better than 1%. Advantages of the proposed technique over existing plastic microfabrication techniques are discussed in the paper. Using this microfabrication technique, we produced a plastic biochip for highly parallelized transfection of arrays of living cells. The feasibility of parallel lipofection was demonstrated: two different plasmids encoding, respectively, eGFP and DsRED2 were inserted into HEK293T cells. The transfection was monitored through fluorescence observation after 72 h showing successful expression of both genes

Entwicklung von Kunststoff-Mikroventilen im Batch-Verfahren

Ziel der vorliegenden Arbeit ist es, die Integration von Materialien in Mikrosysteme zu ermöglichen, welche sich nicht für monolitische Herstellungs- und Integrationsverfahren eignen. Eine aufwändige und somit meist kostspielige Pick-and-Place Montage wird dabei hinsichtlich der wirtschaftlichen Eignung auch für größerer Stückzahlen durch Übertragungstechniken auf der Waferebene vermieden. Als Demonstratorsystem dient ein Kunststoff-Mikroventil mit einem Aktor aus einer Formgedächtnislegierung

Bistabiles Magneto-Formgedächtnis-Mikroventil

Bistable actuators only consume energy during the switching process. This characteristic renders these kind of actuators extremely interesting for applications in the field of microfluidics. This work presents a novel principle of bistable actuation, which combines an antagonistic shape memory alloy (SMA) actuation mechanism with magnetostatic latching. A bistable microvalve, using this principle is demonstrated

Backside liquid Phase Photolitography for Fabricating self-organizing hydrogel bilayers

We propose a backside exposure liquid phase photolithography platform for the fabrication of polymer microsystems. While conventional process strategies require a solidified polymer film prior to exposure, we utilize polymer encapsulation in order to directly cross-link the polymer from solution. Silane-based surface passivation and lift-off resist are used to control polymer adhesion after removal of the encapsulation. This process platform offers many attractive features including self-aligned processing of multilayer arrangements and controlled release capabilities. The fabrication of a drug delivery vehicle made from self-organizing hydrogel bilayers is a target application of this research