Application of a PDMS microstencil as a replaceable insulator toward a single-use planar microelectrode array

Abstract

Here we present a novel idea for a replaceable insulator, and thus advance toward the goal of a single-use planar microelectrode array (MEA) for the study of electrogenic tissues. The concept of a replaceable insulator is motivated by insulator degradation after repeated usage of an MEA. Instead of fabricating a more durable insulator for repeated MEA usage, we propose replacing the insulator and effectively producing a fresh MEA for each experiment. We chose a polydimethylsiloxane (PDMS) microstencil as a candidate for the replaceable insulator as it is biocompatible, shows reversible adhesion to surfaces, and can be easily and controllably fabricated. As a proof-of-concept, we demonstrate two applications using microstencils: the rejuvenation of an old MEA and the fabrication of a single-use MEA. These MEAs were tested with dissociated neural cell cultures and neural recordings were performed at 14 days in vitro. Inexpensive and quick supply of insulators with micrometer-sized holes provides a way of constructing an MEA that can be treated as a disposable component in high throughput cell-based biosensor applications.

Elastomer Application in Microsystem and Microfluidics

“…Additionally, the micropatterned PDMS insulation can be applied to biosensing microdevices such as in an extensive neuronal network. Other researchers used PDMS to develop a replaceable insulator for a single-use planar microelectrode array (MEA) in the study of electrogenic tissues 40 . They demonstrated applications using microstencils for rejuvenation of an old MEA and the fabrication of a single-use MEA.…”

Toward the Precise Control of Cell Differentiation Processes by Using Micro and Soft Lithography

“…PDMS is well used elastomeric material in cell engineering research because of its capability of easy processing, biocompatibility and cell-nonadhesiveness (Mata et al, 2005). PDMS is also an insulative material (Nam et al, 2006) and thus useful for insulator as the SU-8 structures used in section 2. By using the cell-adhesive electrode substrate with the PDMS sheet and plating P19 cells onto it, we attempted to obtain a large number of EBs and stimulate them.…”

“…In this experiment, 289 (17  17 matrix pattern) and 64 columns (8  8 matrix pattern) were fabricated for 200 and 500 m diameter microcavities, respectively. Before pouring PDMS, a thin layer of photoresist (OFPR-800, positive photoresist, Tokyo Ohka) with a thickness of 4 m was formed onto the substrate by spin-coating for 40 s at 2000 rpm and then baking for 30 min at 80 o C. The thin photoresist layer worked as a sacrifice layer to release a cured PDMS sheet from the substrate (Nam et al, 2006). Then, the mixture of PDMS pre-polymer and catalyst (10:1 ratio, Silpot 184, Dow Corning) was spin-coated on the substrate for 80 s at 2500 rpm and 40 s at 2000 rpm, for 200 and 500 m diameter microcavites, respectively.…”

Development of a Neural Interface for PNS Motor Control

“…Such an approach to neural interfaces would render the cultured probe effectively a cell-based biosensor [86]. Prior to being deployed in animal studies, these technologies are developed and tested in vitro in the form of modified planar MEAs [81,[87][88][89][90][91][92]. Much of the work done to date interfacing MEAs with cells in vitro has been performed with applications in two cell systems [86,93]: 1) neurons, where the ability to identify the activity of single cells in spike trains through a process called "spike-sorting" is used to identify patterns of population activity and network dynamics and 2) cardiac myocytes, where spatial and temporal resolution allow the measurement of transduction velocity through sheets of linked cardiomyocytes.…”