A microfluidic chip analyzer for determining neurotransmitters

Abstract

The fabrication of a chip analyzer based on polydimethylsiloxane and glass has been described. The possibilities of the treatment of the chip channel surface by atmospheric plasma and sodium dodecyl sul phate used as an additive to the working buffer solution has been studied. The rate of electroosmotic flow was evaluated. Using a model mixture of catecholamines, the effect of modification of the surface of microchip channels on efficiency and separation factor was revealed. Methods for enhancing the sensitivity of the elec trochemical cell have been developed; the possibilities of online preconcentration in the chip format were evaluated. The limit of detection for catecholamines has been attained at 10 -6 -10 -7 g/mL.

A microfluidic chip for the determination of polyphenolic antioxidants

“…The possibilities of two configurations, off channel and in channel, were revealed in [6]. The best results were achieved with the arrangement of electrodes per pendicular to the field of the high voltage source (electrodes were parallel to the electrolyte flow, an in channel two electrode configuration), because, in this case, the effect of the high voltage source on current in the cell was the minimum.…”

“…Microfluidic chip analyzer is a system consisting of a chip for capillary electrophoresis, included into an analytical setup [6]. The analytical setup consists of a high voltage source, an amperme ter, a control unit for supplying voltage to the elec trodes, and a unit interfacing the setup to a computer.…”

“…The manufacturing of a chip was described previ ously [6] and included the following steps: manufac turing of a silicon matrix for molding a polymer part of the chip; molding the polymer part of the chip of poly dimethylsiloxane (PDMS); making gold electrodes for an object glass; and joining of the polymer and glass parts.…”