Use of bioaffinity interactions in electrokinetically controlled assays on microfabricated devices

Abstract

In this contribution, the role of bioaffinity interactions on electrokinetically controlled microfabricated devices is reviewed. Interesting applications reported in the literature include enzymatic assays, where enzyme and enzyme inhibition kinetics were studied, often in combination with electrophoretic separation. Attention is paid towards developments that could lead to implementation of electrokinetically controlled microdevices in high-throughput screening. Furthermore, enzyme-facilitated detection in combination with electrophoretic separation on microdevices is discussed. Various types of immunoassays have been implemented on the microchip format. The selectivity of antibody-antigen interaction has been exploited for the detection of analytes in complex sample matrices as required, for example, in clinical chemistry. Binding kinetics as well as stoichiometry were studied in chip-based assays. Automated mixing protocols as well as the demonstration of a parallel immunoassay allow implementation of microdevices in high-throughput screening. Furthermore, demonstration of immunoassays on cheap polymeric microdevices opens the way towards the fabrication of disposable devices, a requirement for commercialization and therefore for application in routine analyses.

Nonlinear phenomena and qualitative evaluation of risk of clogging in a capillary microreactor under imposed electric field

“…The interest in microtechnology and nanotechnology in the last decade has evoked an intensive research on the electrokinetic phenomena in microstructures particularly on the effects of the electric field on processes inside microcapillaries and more complex microstructures [6][7][8][9]. An external electric field can evoke electroosmotic flow inside the microreactor and thus the electroosmotic transport of electrolytes is widely used for dosing, pumping, and mixing in microchannels.…”

A rapid enzyme assay for � -galactosidase using optically gated sample introduction on a microfabricated chip

“…Microfabricated capillary electrophoresis (microCE) chips have been widely applied to many areas, including protein analysis, DNA fragment analysis, and other research areas [3,5,6,7,8,9,10]. The advantages of microCE chips are in particular small sample requirements, fast response time, and ease of multiplexing microstructures.…”

Measurement of neuropeptides in clinical samples using chip-based immunoaffinity capillary electrophoresis

“…There is also the issue of sample size, which becomes important when pediatric and precious archival samples are concerned. Guijt et al (2002) reviewed the role of bio-affinity in chip-based analytical systems, with special reference to electrokinetic immunoassays.…”