A highly reliable integrated PDMS interconnector with a long cast flange for microfluidic systems

Abstract

This paper presents a highly reliable macro to micro domain interconnection technology for microfluidic applications using Polydimethylsiloxane (PDMS) casting techniques. Characteristic to the interconnectors are long flanges fabricated in the PDMS film; therefore the contact area between PDMS and tubes is considerably increased compared to other interconnection technologies. Thus, both glass capillaries and Polytetrafluoroethylene (PTFE) tubes can be held in position very reliably and rigidly. To test the reliability of the interconnectors, PTFE tubes were successfully connected to microfluidic chips without the aid of any liquid adhesives. Both leakage and pull-out tests demonstrated the functionality and reliability of the PDMS interconnectors; no leakage was detected under a working pressure up to 400 kPa. A pull-out test yielded a pull-out force of 22.45 N. Furthermore, once a casting mould is fabricated, it can be re-used as a template repeatedly achieving a low cost technology and making it suitable for batch production.

Lab-on-a-chip devices: How to close and plug the lab?

“…They reported maximum burst pressures up to 15.6 MPa. Similar molding techniques for monolithic integration of connectors were later applied to microfluidic chips based on PDMS [201,202] and OSTE polymer [203]. Welding and bonding were also employed.…”

Development of an on-chip sample injection system with a 6-port valve incorporated in a microchip

“…To decrease the dead volume at the tubing connections between the microchip and the outside macro-world, some researchers have developed uidic interconnection techniques, such as a ball-joint connection, 18 an interference t connection, 19,20 and connections using a convex-type or a long cast ange shaped polydimethylsiloxane (PDMS). 21,22 Further, van Swaay et al 23 developed a simple and inexpensive chip-to-world connector with a sample injection port. Here, sample is added with a micropipette into a reservoir in the connector, and introduction of the sample to a microchannel was achieved by a syringe pump aer sealing the reservoir with a sliding cap.…”

A continuously tunable size-based filter

“…Another commonly found problem to the microsieve filtration is the clogging of the pores. To overcome this, we used a time-sequential flow rate control, i.e., a back-and-forth flow pattern generated by the 2-port interconnection [8], to clean the clogging (Fig. 4).…”