High-aspect-ratio through-hole array microfabricated in a PMMA plate for monodisperse emulsion production

Abstract

Microchannel (MC) emulsification is a promising technique for producing monodisperse emulsions consisting of highly uniform droplets. The authors developed a high-aspect-ratio microstructure (HARMST) made of poly(methyl methacrylate) (PMMA) as a new MC emulsification device. A PMMA straight-through MC array plate consisting of 31,250 through-holes with a 7.3 9 22.9-lm oblong section and a 200-lm depth was fabricated by a process of synchrotron radiation (SR) lithography and etching. Oblong MCs fabricated in a PMMA straightthrough MC array were highly uniform with a coefficient of variation of less than 2%. The fabricated PMMA straight-through MC array plate was used to produce waterin-oil (W/O) emulsions. Monodisperse W/O emulsions with average droplet diameters of approximately 25 lm and a minimum coefficient of variation of 3.2% were produced via a hydrophobic PMMA straight-through MC array. The PMMA straight-through MC array plate also produced monodisperse W/O emulsions at droplet production rates of up to 1.7 9 10 4 /s. The PMMA straightthrough MC array plates developed in this work are expected to expand the application field of emulsification using straight-through MC array plates, which have previously been made of single-crystal silicon.

Off‐Chip Vertical Step Emulsification Droplets Preparation Device Applied for Droplet Digital PCR

“…One is chamber-based, [6][7][8] and the other is droplet-based. [9][10][11] The chamberbased dPCR devices need to process tens of thousands of microreactors with the same volume on substrates of different materials (such as polydimethylsiloxane [PDMS], [12] polymethyl methacrylate [PMMA], [13] fused silica, [10] silicon, [14] etc. ), and then the reagents are separated into each microreactors for PCR reaction.…”

Structured microparticles with tailored properties produced by membrane emulsification

“…It is especially important in PME, where whole emulsion, rather than a pure dispersed phase, is pressed through the membrane. Typical microsieves used in ME are nickel microengineered membranes manufactured using UV-LIGA process (Nazir et al, 2011;Schadler and Windhab, 2006;Egidi et al, 2008), silicon nitride Aquamarijn microsieves fabricated by reactive ion etching (RIE) (van Rijn et al, 1997), stainless steel membranes fabricated by pulsed laser drilling (Dowding et al, 2001;Vladisavljević and Williams, 2006;Geerken et al, 2008) or end-milling , and microchannel arrays fabricated in single crystal silicon by Deep Reactive Ion Etching (DRIE) (Kobayashi et al, 2003) or in PMMA by X-ray lithography and wet etching (Kobayashi et al, 2008b). The fabrication of microengineered membranes for ME is described by Vladisavljević et al (2012).…”

Micro segmented flow-functional elements and biotechnical applications

“…The most widely used microchip material reported in public domain is polydimethylsiloxane (PDMS) since it is easy to pattern, optically transparent, flexible and biocompatible (64). However, due to the drawbacks such as absorption and inability for mass production (65), many alternative polymeric materials are used for fabrication of microchips, such as polymethylmethacrylate (PMMA) (65)(66)(67)(68), polyester (69) and cyclic-olefin-copolymer (COC) (70). Besides polymeric materials, glass (44) and silicon (71) have also been widely used as microchip material for biological studies.…”