In this paper, we propose a novel microfluidic tunable metamaterial (MM) absorber printed on a paper substrate in silver nanoparticle ink. The metamaterial is designed using a periodic array consisting of square patches. The conductive patterns are inkjet-printed on paper using silver nanoparticle inks. The microfluidic channels are laser-etched on polymethyl methacrylate (PMMA). The conductive...

We demonstrate new principles of microfluidic pumping and mixing by electronic components integrated into a microfluidic chip. The miniature diodes embedded into the microchannel walls rectify the voltage induced between their electrodes from an external alternating electric field. The resulting electroosmotic flows, developed in the vicinity of the diode surfaces, were utilized for pumping or ...

A current problem in microfluidics is that poly(dimethylsiloxane) (PDMS), used to fabricate many microfluidic devices, is not compatible with most organic solvents. Fluorinated compounds are more chemically robust than PDMS but, historically, it has been nearly impossible to construct valves out of them by multilayer soft lithography (MSL) due to the difficulty of bonding layers made of "non-st...

This study presents a finger-triggered portable polydimethylsiloxane suction cup that enables equipment-free microfluidic pumping. The key feature of this method is that its operation only involves a “pressing-and-releasing” action for the cup placed at the outlet of a microfluidic device, which transports the fluid at the inlet toward the outlet through a microchannel. This method is simple, b...

Microfluidic technology provides precise, controlled-environment, cost-effective, compact, integrated, and high-throughput microsystems that are promising substitutes for conventional biological laboratory methods. In recent years, microfluidic cell culture devices have been used for applications such as tissue engineering, diagnostics, drug screening, immunology, cancer studies, stem cell prol...

Red blood cells play a crucial role in the local regulation of oxygen supply in the microcirculation through the oxygen dependent release of ATP. Since red blood cells serve as an oxygen sensor for the circulatory system, the dynamics of ATP release determine the effectiveness of red blood cells to relate the oxygen levels to the vessels. Previous work has focused on the feasibility of developi...

A microfluidic tactile sensing device has been first reported for three-dimensional contact force measurement utilizing the microfluidic interfacial capacitive sensing (MICS) principle. Consisting of common and differential microfluidic sensing elements and topologically micro-textured surfaces, the microfluidic sensing devices are intended not only to resolve normal mechanical loads but also t...

Rapid prototyping of microfluidic systems using a combination of double-sided tape and PDMS (polydimethylsiloxane) is introduced. PDMS is typically difficult to bond using adhesive tapes due to its hydrophobic nature and low surface energy. For this reason, PDMS is not compatible with the xurography method, which uses a knife plotter and various adhesive coated polymer tapes. To solve these pro...

Microfluidic systems use networks of channels thinner than a human hair to manipulate nanoliter volumes of reagents. The goal of microfluidics is challenging: to integrate, on a chip smaller than a credit card, all operations normally performed in a chemical or medical laboratory. Synthesis, purification, analysis, and diagnostics would be performed by such a “lab on a chip” rapidly, economical...

In microfluidics, electric fields are widely used to assist the generation and the manipulation of droplets or jets. However, uncontrolled electric field can disrupt the operation of an integrated microfluidic system, for instance, through undesired coalescence of droplets, undesired changes in the wettability of the channel wall or unexpected death of cells. Therefore, an approach to control t...