Disposable microfluidic ELISA for the rapid determination of folic acid content in food products.

A micro-analytical system for rapid and quantitative analysis by inhibition immunoassay is presented and applied to the detection of folic acid. Eight polymer microchannels of 65-nL volume each and containing microelectrodes are embedded in a cartridge so that they can be operated simultaneously. All fluidic steps as well as the amperometric detection in the channels are operated by an instrument and software developed in-house.

Proteome analysis of human plasma and amniotic fluid by Off-Gel isoelectric focusing followed by nano-LC-MS/MS.

This paper presents a comparative proteomic analysis of human maternal plasma and amniotic fluid (AF) samples from the same patient at term of pregnancy in order to find specific AF proteins as markers of premature rupture of membranes, a complication frequently observed during pregnancy. Maternal plasma and the corresponding AF were immunodepleted in order to remove the six most abundant proteins before the systematic analysis of their protein composition. The protein samples were then fractionated by IEF Off-Gel electrophoresis (OGE), digested and analyzed with nano-LC-MS/MS separation, revealing a total of 73 and 69 proteins identified in maternal plasma and AF samples, respectively.

Added value for tandem mass spectrometry shotgun proteomics data validation through isoelectric focusing of peptides.

A very popular approach in proteomics is the so-called "shotgun LC-MS/MS" strategy. In its mostly used form, a total protein digest is separated by ion exchange fractionation in the first dimension followed by off- or on-line RP LC-MS/MS. We replaced the first dimension by isoelectric focusing in the liquid phase using the Off-Gel device producing 15 fractions.

Two-stage Off-Gel isoelectric focusing: protein followed by peptide fractionation and application to proteome analysis of human plasma.

This paper presents the recently introduced Off-Gel electrophoresis (OGE) technology as a versatile tool to reproducibly fractionate intact proteins and peptides into discrete liquid fractions. The coupling of two stages of OGE, i.e.

Gravity-induced convective flow in microfluidic systems: electrochemical characterization and application to enzyme-linked immunosorbent assay tests.

A way of using gravity flow to induce a linear convection within a microfluidic system is presented. It is shown and mathematically supported that tilting a 1 cm long covered microchannel is enough to generate flow rates up to 1000 nL.min(-1), which represents a linear velocity of 2.