Total analysis system , concept

The feasibility of constructing a miniaturised system including reaction, separation and detection units integrated directly onto the EC-CE microchip device has also been shown and approximates the concept of total analysis system . Furthermore, the low cost of the EC detection in connection with new polymer material can bring a real disposable device. 

Micro Total Analysis Systems Microfluidic Aspects, Integration Concept and Applications... 

The concept of an total analysis system (TAS) was presented early by Widmer [87] and was extended to a pTAS concept by Manz [88]. In contrast to sensor systems such systems are based on unspecific sensors gaining the selectivity by separation principles. Electrophoresis devices are good candidates for miniaturization saving time and reducing production costs. Further details are given in various chapters in this book. 

Darhuber, A.A., Davis, J.M., Reisner, W.W., Troian, S.M., Thermocapillary migration of liquids on patterned surfaces design concept for microfluidic delivery. Micro Total Analysis Systems, Proceedings 5th pZAS Symposium, Monterey, CA, Oct. 21-25, 2001, 244-246. 

Hibara, A., Kasai, K., and Miyaguchi, H., et al. Novel two-phase flow control concept and multi-step extraction microchip, in "Proceedings of Micro Total Analysis Systems 2008" (L. E. Locascio, M. Gaitan, B. M. Paegel, D. J. Ross, W. N. Vreeland Eds.), pp. 1326-1328. Chemical and Biological Microsystems Society, San Diego, USA, (2008). 

A. van den Berg, T.S.J. Lammerink, Micro total analysis systems microfluidic aspects, integration concept and applications, Top. Curr. Chem. 194 (1997) 21. 

The first miniaturized analytical device reported was a gas chromatographic analyzer fabricated from silicon in 1979. The work showed the separation of a simple mixture of compounds in only a few seconds. While unperfected, this was an example unlike anything else reported in the literature at that time, and while the scientific community did not immediately grasp the achievements of Terry and coworkers, they did see a glimpse of the future provided in this work with respect to the value of miniaturizing analytical methods. Multiple papers followed this initial work in miniaturization over the next 12 years however, it was not until the concept of a total analysis system (TAS) was first proposed by Manz et al. in 1990 that the concept of miniaturization began to have a significant impact. 

Dispersion, the tendency for ordered molecules to decrease gradients and local concentration, is caused by both molecular diffusion and nonuniform bulk liquid motion. High dispersion rates may be advantageous for mixing and chemical reactions, but are undesirable in separation and purification applications. For separations, minimizing dispersion improves resolution and sensitivity [3] and yields improved dynamics for concentration and purification [4]. As a consequence, the physical processes that lead to dispersion have been a subject of intense interest for more than a century. In recent years, the development of the concept of the micro-total analysis system (p,TAS) or labs on a chip has motivated further exploration of dispersion in microchannel flows. 

---