Facile Fabrication of Thin-Bottom Round-Well Plates Using the Deformation of PDMS Molds and Their Application for Single-Cell PCR

Abstract

Recently, microdevices made of resins have been strongly supporting cell analysis in a range of fields, from fundamental life science research to medical applications. Many microdevices are fabricated by molding resin to a mold made precisely from rigid materials. However, because dimensional errors in the mold are also accurately printed to the products, the accuracy of the product is limited to less than the accuracy of the rigid mold. Therefore, we hypothesized that if dimensional errors could be self-corrected by elastic molds, microdevices could be facilely fabricated with precision beyond that of molds. In this paper, we report a novel processing strategy in which an elastic mold made of polymethylsiloxane (PDMS) deforms to compensate for the dimensional error on the products. By heat-press molding a polycarbonate plate using a mold that has 384 PDMS convexes with a large dimensional error of height of ± 15.6 µm in standard deviation, a 384-round-well plate with a bottom thickness 13.3 ± 2.3 µm (n = 384) was easily fabricated. Finally, single-cell observation and polymerase chain reactions (PCRs) demonstrated the application of the products made by elastic PDMS molds. Therefore, this processing method is a promising strategy for facile, low-cost, and higher precision microfabrication.

Editorial for the Special Issue on Micro and Nano Devices for Cell Analysis

“…Of the T790M-mutated cancer cells (NCI-H1975) that spiked into non-mutated cancer cells (A549), 0–20% were difficult for a conventional next-generation sequencer (NGS) and were quantitatively analyzed within 1 h. Therefore, this system could be useful in analyzing cancer tissue that contains a few anticancer drug-resistant cancer cells. Yamahira et al [ 3 ] proposed a novel processing method in which an elastic mold made of polymethylsiloxane (PDMS) deforms to compensate for the dimensional error on the products. By heat-press molding a polycarbonate plate using a 384 PDMS convexes mold made from an acrylic sheet with 384 holes, a 384-round-well plate with a bottom thickness of 13.3 ± 2.3 mm ( n = 384) was easily and accurately fabricated.…”