Fabrication of poly(methyl methacrylate) microfluidic chips by redox‐initiated polymerization

Abstract

In this report, a method based on the redox-initiated polymerization of methyl methacrylate (MMA) has been developed for the rapid fabrication of poly(methyl methacrylate) (PMMA) microfluidic chips. MMA containing 2-2'-azo-bis-isobutyronitrile was allowed to prepolymerize in a water bath to form a viscous prepolymer solution that was subsequently mixed with MMA containing a redox-initiation couple of benzoyl peroxide/N,N-dimethylaniline. The dense molding solution was sandwiched between a silicon template and a piece of 1-mm-thick PMMA plate. The polymerization could complete within 50 min under ambient temperature. The images of raised microfluidic structures on the silicon template were precisely replicated into the synthesized PMMA substrate during the redox-initiated polymerization of the molding solution. The chips were subsequently assembled by the thermal bonding of the channel plates and the covers. The new fabrication approach obviates the need for special equipment and significantly simplifies the process of fabricating PMMA microdevices. The attractive performance of the novel PMMA microchips has been demonstrated in connection with contactless conductivity detection for the separation and detection of ionic species.

Fabrication, modification, and application of poly(methyl methacrylate) microfluidic chips

“…More recently, a novel approach based on the redox-initiated in situ surface polymerization of MMA has been developed for the rapid fabrication of PMMA microfluidic chips [28]. Figures 2A2E illustrate the microfabrication process.…”

“…The procedure allowed satisfactory separations without interference from common inorganic anions such as sulfate and nitrate. Recently, a PMMA electrophoresis microchip fabricated by redox-initiated polymerization was employed to determine potassium, sodium, and chloride in human urine coupled with contactless-conductivity detection [28]. The determined contents fall in the ranges of the reference values.…”

Fabrication of PMMA CE microchips by infrared‐assisted polymerization

“…A homemade 13000 V high-voltage dc power supply provided a voltage for the electrophoretic separation and the electrokinetic sample introduction. The capacitively coupled contactless conductivity detector was used for the detection of ionic species [19,21]. A VC 2002 function generator (Shenzhen Victor Electronics, Shenzhen, China) was used to generate a sinusoidal signal with a frequency of 250 kHz with peak-topeak amplitude of 5 V that was applied to the CCD electrode pairs on the cover sheet of the PMMA electrophoresis microchip.…”

“…The images of the raised microchannels on a nickel template were precisely replicated into the synthesized PMMA substrates during the UV-initiated polymerization of the MMA prepolymer molding solution sandwiched between the template and a PMMA plate within 30 min under ambient temperature. More recently, a novel method based on the redox-initiated polymerization of MMA has been developed for the rapid and easy fabrication of PMMA CE microchips [19]. As an important form of electromagnetic waves, the infrared (IR) ray has wavelengths between about 750 nm and 1 mm and has found a wide range of applications [20].…”

A low‐leakage sample plug injection scheme for crossform microfluidic capillary electrophoresis devices incorporating a restricted cross‐channel intersection

“…Today's state-of-the-art micromachining techniques enable a network of microfluidic devices to be fabricated on a single glass [8][9][10], poly(methyl methacrylate) (PMMA) [11,12], PDMS [13,14], polycarbonate (PC) [15,16], or quartz [17] substrate and therefore make possible the realization of complete chemical or biological analysis systems on a single platform. Such systems are commonly referred to as micro-total analysis systems (m-TAS) or lab-on-a-chip (LoC) devices [18][19][20][21][22][23][24][25] and typically integrate multiple functional units designed to carry out sample separation and collection, DNA restriction, sample manipulation and mixing, DNA amplification, PCR, cell sorting and counting, mixing, clinical and forensic analysis, online detection, and so forth.…”