Power-free poly(dimethylsiloxane) microfluidic devices for gold nanoparticle-based DNA analysisElectronic supplementary information (ESI) available: Sample movie used for flow characterization, mathematical details of the one-dimensional diffusion model, and time course of the gold nanoparticle deposition. See http://www.rsc.org/suppdata/lc/b4/b403930k/

Abstract

An extremely simple, power-free pumping method for poly(dimethylsiloxane)(PDMS) microfluidic devices is presented. By exploiting the high gas solubility of PDMS, the energy for the pumping is pre-stored in the degassed bulk PDMS, therefore no additional structures other than channels and reservoirs are required. In a Y-shaped microchannel with cross section of 100 microm width x 25 microm height, this method has provided flow rate of 0.5-2 nL s(-1), corresponding to linear velocity of 0.2-0.8 mm s(-1), with good reproducibility. As an application of the power-free pumping, gold nanoparticle-based DNA analysis, which does not rely on the cross-linking mechanism between nanoparticles, has been implemented in a microchannel with three inlets. Target 15mer DNA has been easily and unambiguously discriminated from its single-base substituted mutant. Instead of colorimetric detection in a conventional microtube, an alternative detection technique suitable for microdevices has been discovered-observation of deposition on the PDMS surfaces. The channel layout enabled two simultaneous DNA analyses at the two interfaces between the three laminar streams.

Towards autonomous lab-on-a-chip devices for cell phone biosensing

“…In this case whole blood is propelled using a self-powered evacuated dead-end microchannel (Hosokawa et al, 2004(Hosokawa et al, , 2006, which needs to be preserved in a vacuum pouch previous to operation, although the principle could be adapted to other forms of self-propulsion (Wang et al, 2010;Kokalj et al, 2014;Zimmermann et al, 2007;Gervais and Delamarche, 2009) or finger pumps (Comina et al, 2015a;Begolo et al, 2014). The deep trench type of separation feature is also very compatible with 3D printed LOC devices (Comina et al, 2014a(Comina et al, , 2015b and minimizes the number of components and fabrication steps.…”

Direct detection of cancer biomarkers in blood using a “place n play” modular polydimethylsiloxane pump

“…In this chip, fluid was pumped with a unique, self-priming, degassing-driven flow technique. 39 To increase the pumping energy of degassed PDMS, an array of supporting posts was fabricated in each pumping chamber to increase the area for absorbance of air. 40 The PDMS layer and PDMS stamp were fabricated using the soft lithography replica molding technique.…”

Automatic sequential fluid handling with multilayer microfluidic sample isolated pumping

“…[12][13][14] Most of the passive fluidic actuation methods lack effective positive control method or actuation reproducibility. [15][16][17][18][19] Take degas-driven flow as an example, it takes advantage of the Polydimethylsiloxane (PDMS) material to overcome the undesired bubble formation and enclosed chamber loading issue; however, it does not support a) Author to whom correspondence should be addressed. Electronic mail: lisongjing@hit.edu.cn.…”