Micro total analysis/analytical systems

Micro Total Analysis Systems (pTAS) are chip-based micro-channel systems that serve for complete analytics. The word Total refers to the monolithic system character of the devices, integrating a multitude of miniature functional elements with minimal dead volumes. The main fields of application are related to biology, pharmacology, and analytical chemistry. Detailed applications of pTAS systems are given in Section 1.9.8. Recently, pTAS developments have strongly influenced the performance of organic syntheses by micro flow (see, e.g., [29]). By this, an overlap with the micro-reactor world was made, which probably will increase more and more. 

D. R., Manz, a.. Micro total analysis systems 2. Analytical standard operations and applications. Anal. Chem. 74,12 (2002) 2637-2652. 

Until now, all in the literature proposed LAPS devices are complete autarkic measurement systems. Further applications can be found by the integration of LAPS devices into existing analytic fields. This requires the development of inexpensive integrated electronic units to operate the LAPS and to provide a standardised communication with higher process levels. The LAPS devices need to be easy in use to allow the operation in commercial environments. Due to the simple structure of the LAPS, the integration into micro-electro-mechanical systems (MEMS), lab-on-chip and micro-total analysis systems (p-TAS) might be of special interest in the near future. 

Miniaturisation and automatisation of analytical and bioanalytical systems have had a great development in the last decade. The final goal of miniaturised devices is represented by micro-total analysis systems (g-TAS), also called lab-on-a-chip (LOC). These devices bring advantages in terms of mass production, low cost and disposability as well as speed, high performance, portability and low energy requirements. 

Weigl, B.H., Kriebel, J., Mayes, K., Yager, P., Wu, C.C., Holl, M., Kenny, M., Zebert, D., Simultaneous self-referencing analyte determination in complex sample solutions using microfabricated flow structure (T-sensors). Micro Total Analysis Systems 98, Proceedings pTAS 98 Workshop, Banff, Canada, 13-16 Oct. 1998, 81-84. 

Rehm, J.E., Shepodd, T.J., Hasselbrink, E.F., Jr. Mobile flow control elements for high-pressure micro-analytical systems fabricated using in-situ polymerization. Micro Total Analysis Systems, Proceedings 5th i7AS Symposium, Monterey, CA, Oct. 21-25, 2001, 227-229. 

Yager, P., Cabrera, C., Hatch, A., Hawkins, K., Holl, M., Kamholz, A., Macounova, K., Weigl, B.H., Analytical devices based on transverse transport in microchannels. Micro Total Analysis Systems, Proceedings of the 4th iTAS Symposium, Enschede, Netherlands, May 14-18, 2000, 15-18. 

Blankenstein, G., Scampavia, L., Branebjerg, J., Larsen, U.D., Ruzicka, J., Flow switch for analyte injection and cell/particle sorting. Micro Total Analysis Systems 96, Proceedings of 2nd International Symposium on pTAS, Basel, 19-22 Nov. 1996, 82-84. 

Recent breakthroughs in miniaturized analytical instrumentation include fully integrated lab-on-a-chip and micro total analysis systems. The former have had only moderate success as many analytical chemists have been reluctant to accept them [67]. At present, chip-based analytical systems are subject to major shortcomings such as the risk of analyte adsorption on walls and at interfaces — which is important especially in low-volume analytical systems — and optical interference at the walls of the chips hampering detection. Further research in this field is required in order to effectively circumvent these shortcomings [68]. 

Arora, A., Simone, G., Salieb-Beugelaar, G.B., Kim, J.T., and Manz, A. (2010) Latest developments in micro total analysis systems. Analytical Chemistry,... 

The development of flow systems has contributed to a decrease in the volume of samples and reagents needed for a particular chemical analysis. This tendency was reinforced with the advent of micro-scale analytical methods relying on, e.g., electrophoresis and micro-total analysis systems (pTAS), which influenced the introduction of miniaturised flow systems. Miniaturisation achieves a significant reduction in sample and reagent consumption and allows the design of compact and portable systems. As a result, the generation of chemical waste and the cost of analysis are reduced, and the possibility for in situ or in vivo assays is increased. Thus, in recent years, several miniaturised flow systems have been proposed. 

Capillary electrophoresis systems were the first micro total analysis systems and emerged as single chip solutions from the analytical chemistry field in the 1990s [254]. Several companies utilize microfluidic capillary electrophoretic chips for chemical analysis, with capillaries of typically 10-100 pm diameter [255]. 

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