At the heart of the laboratory on a chip are chemical or biochemical probes designed to detect specific molecules or reaction products. For these probes to perform their function, a microfluidic "plumbing system" is needed to accept samples, then manipulate, dispense, and distribute tiny liquid volumes on the chip. The most promising mechanisms for handling such small quantities of liquid -from...

A micro-free flow electrophoresis (µFFE) analytical system with voltage applied in two dimensions was proposed. Both fluid transport and separation were driven electrokinetically. The Alpha-Imager was applied as an in-situ detector, which could observe, scan and analyze the photometric state of the whole separating area. The mass-transfer process and the range of voltages applied on the chip we...

Coupled cell-free transcription-translation (CFTT) of green fluorescent protein (GFP) has been applied as a reporter system to microfluidic chip-related technologies. In polymerase chain reaction (PCR)-based biomolecular logic gate system, in which addition of primer set and amplification of PCR product represent input and output signal respectively, GFP gene was inserted in the template DNA, w...

A micro supported lipid bilayer (SLB) electrophoresis method was developed, which functions at low potentials and appreciable operating times. To this end, (hydroxymethyl)-ferrocene (FcCH2OH) was employed to provide an electrochemical reaction at the anode and cathode at low applied potential to avoid electrolysis of water. The addition of FcCH2OH did not alter the SLB characteristics or affect...

We have developed an acrylic microfluidic device that sequentially couples liquid-phase isoelectric focusing (IEF) and free solution capillary electrophoresis (CE). Rapid separation (<1 min) and preconcentration (73x) of species were achieved in the initial IEF dimension. Using full-field fluorescence imaging, we observed nondispersive mobilization velocities on the order of 20 microm/s during ...

A microfluidic channel and a contactless capacitance detector were integrated on a glass chip by a semiconductor manufacturing process for separating and analyzing Rhodamine B and inorganic ion. The electrodes of the capacitance detector were formed successively by sputtering, electroless and electrodepositions. Samples containing fluorescent agent (Rhodamine B) and inorganic ions (K, Na, and L...

We present an experimental study of the effect of pH, ionic strength, and concentrations of the electroosmotic flow (EOF)-suppressing polymer polyvinylpyrrolidone (PVP) on the electrophoretic mobilities of commonly used fluorescent dyes (fluorescein, Rhodamine 6G, and Alexa Fluor 488). We performed on-chip capillary zone electrophoresis experiments to directly quantify the effective electrophor...

Mutations in the tumor suppressor gene TP53 are associated with a wide range of different cancers and may have prognostic and therapeutic implications. Methods for rapid and sensitive detection of mutations in this gene are therefore required. In order to make screening more effective, a commercially available TP53 genotyping microarray from Asper Biotech has been constructed by arrayed primer ...

Two major components of rRNA (18S and 28S rRNA) were separated by electrophoresis in injection-molded acrylic chips with a microchannel 100 microm in width, 40 microm in depth, and with 1 cm of separation distance. Microchannels were filled with 4 g/L hydroxypropylmethylcellulose as sieving polymer and 5 mg/L ethidium bromide for RNA staining. The fluorescent signals were detected by a fluoresc...