Bonding of thermoplastic polymer microfluidics

Abstract

Thermoplastics are highly attractive substrate materials for microfluidic systems, with important benefits in the development of low cost disposable devices for a host of bioanalytical applications. While significant research activity has been directed towards the formation of microfluidic components in a wide range of thermoplastics, sealing of these components is required for the formation of enclosed microchannels and other microfluidic elements, and thus bonding remains a critical step in any thermoplastic microfabrication process. Unlike silicon and glass, the diverse material properties of thermoplastics opens the door to an extensive array of substrate bonding options, together with a set of unique challenges which must be addressed to achieve optimal sealing results. In this paper we review the range of techniques developed for sealing thermoplastic microfluidics and discuss a number of practical issues surrounding these various bonding methods.

Safe and cost-effective rapid-prototyping of multilayer PMMA microfluidic devices

“…microfluidic research, such as PDMS, and mostly relies on methodologies that can lead to severe changes in the morphology of the final product (Tran et al 2013). The need of a reliable and high-throughput bonding method becomes critical as applications are rapidly translated into commercialised products, in particular for clinical products (Tsao and DeVoe 2009;Becker 2010). Additionally, over the last 5 years small milling machines and table-top laser systems have become available and form, besides 3D printing, the bases for the maker movement.…”

Manufacturing and wetting low-cost microfluidic cell separation devices

“…There are numerous methods for bonding homogenous microfluidic devices (devices manufactured with one material). 21 However, these methods are not adequate for manufacturing complex microfluidic devices, such as those requiring the physical properties of different materials (i.e., high Young's modulus and gas permeability). A simple, robust method for bonding different thermoplastic substrates is required.…”

“…Alcohol elution was considered for wetting the devices, but this requires a cytotoxic fluid and significant post-processing to remove alcohol absorbed by the materials. Wet storage may be the most effective option as COPs have low water absorption, 21 however, the permeability of TPEs its effect on long-term thermal bond strength is unknown; further investigation into a cyto-compatible wet-storage fluid is required. In addition to testing wet storage lifetime, a cost-benefit analysis comparing prewetting and wet device storage to pressure-driven wetting is required.…”

An automated microfluidic sample preparation system for laser scanning cytometry

“…Hot embossing has been extensively used for forming microfluidic devices (Tsao and Devoe 2009). Figure 6 illustrates the steps required to make our copper mold.…”