Cost-effective and reliable sealing method for PDMS (PolyDiMethylSiloxane)-based microfluidic devices with various substrates

Abstract

A cost-effective and simply handling bonding method using siloxane-based adhesion promoter is introduced to increase the adhesion strength between cured PDMS and various substrates. The working mechanism of adhesion promoters is based on post-cure reaction in PDMS curing and they have similar chemistry compositions with PDMS prepolymers. It is experimentally investigated and proved that the adhesion strength of the resulted interface depends on -SiH group and Pt catalyst in adhesion promoters and molecular structures and polarity of substrates surfaces. By modifying their compositions uniform and perfect adhesion can be obtained for different substrates and meet different markets requirements, e.g., PDMS and glass which could be applied for biology, chemistry and solar cell fields, FR4 for electronics field and copper for electronics and thermal cooling fields, etc. Also, considering the quality and reliability requirements from potential application markets of microfluidic devices an environmental test procedure is summarized and according to the defined procedure, the environmental stability of realized PDMS-based microfluidic devices with different substrates has been tested with the result that they exhibited excellent stabilities and suitability for mass production.

Electrophoresis separation and electrochemical detection on a novel thread-based microfluidic device

“…However, conventional CE devices rely on fabricating real microchannels in glass, PMMA or PDMS for delivering and separating samples (Cai and Neyer 2010;Hong et al 2010;Hug et al 2006;Hupert et al 2007;Zhu and Petkovic-Duran 2010). Therefore, the cost and preparation of the CE detection system is comparable longer and higher.…”

Development of reversible bonding for microfluidic applications

“…An adhesive layer can also help making a reversible bonding between the channel cap and the bottom substrate (Chong et al 2005;Cai and Neyer 2010;Vézy et al 2011). In the paper (Vézy et al 2011), dimethyl-methylphenylmethoxy siloxane (DMPMS) is used as an adhesive layer and an oxygen plasma treatment is required to form a reversible bonding of DMPMS on different substrates.…”

Viscoelastic nature of Au nanoparticle–PDMS nanocomposite gels

“…32 The enhanced crosslinking is marked by decreasing intensities of Si-H and Si-vinyl stretching occurring at 2159 and 1597 cm −1 , respectively. 30 There is also an equivalent effect on the formation of nanoparticles due to increased temperature.…”

“…However, it is well known that the degree of crosslinking in plain PDMS depends on temperature. 32 Hence, to probe the effect of temperature on the nature of AuPDMS nanocomposites, rheological measurements were performed on gels prepared at different temperatures for a fixed loading of Au nanoparticles. Figure 4 shows G (solid symbols) and G (hollow symbols) for a nanoparticle loading of 0.19 wt% prepared at 26, 36, 46 and 56 • C. For AuPDMS prepared at lower temperatures such as 26 • C, the value of storage modulus is quite low, being less than 5 Pa (figure 4a).…”