Microfluidic emergence

Feynman s suggestion didn t remain in fantasy world. The first microbeam was fabricated in 1982 and the first microspring was fabricated in 1988. Microfluidics emerged in the beginning of the 1980s and has been used in the development of ink-jet printheads, DNA... 

Thus the study of surfaces has emerged as an important focus in the chemical sciences, and the relationship between surfaces of small systems and their performance has emerged as a major technological issue. Flow in microfluidic systems—for example, in micromechanical systems with potential problems of stiction (sticking and adhesion) and for chemistry on gene chips—depends on the properties of system surfaces. Complex heterogeneous phases with high surface areas—suspensions of colloids and liquid crystals—have developed substantial... 

Despite the fact that much effort has been made to model the DMFC system, considerable work remains, particularly in support of the emerging portable designs and systems. Few have treated the dominating effects of two-phase flow. No model to date has sufficient detail to provide a microfluidic theory for portable systems including effects of channel geometry and wettability characteristics of the GDL on fluid flow in the anode or cathode. Modeling studies are needed to fully elucidate the intricate couplings of methanol, water, and heat-transport... 

Iordache, M. and Jelen, P. (2003). High pressure microfluidization treatment of heat denatured whey proteins for improved functionality. Innou. Food Sci. Emerg. Technol. 4, 367-376. 

The front-tracking method is only one example of computational tools that can be used in analysis and design of microfluidic systems. The computational methods for multiphase/fluid flows have been matured enough that they can be safely used as a design tool in microfluidics. In addition, they can be also very useful to discover or understand new flow physics emerging from the miniaturization of flow systems. 

At the same time, much simpler yet very successfiil microfluidic analysis systems based on wettable fleeces emerged First very simple dipsticks for e.g. pH measurement based on a single fleece paved the way for more complex test strips that have been sold as lateral-flow tests in the late 1980s [14]. Examples that are still on the market today are test strips for pregnancy [15], drug abuse [16-18], cardiac markers [19] and also upcoming bio-warfare protection [20]. 

This short summary shows that there is the potential for many novel applications and improvements over the state-of-the-art within the above-mentioned criteria of sensitivity, cost, time, and size. However, despite a myriad of publications about microfluidic components, principles and applications, very few successful products with a relevant market share have emerged from this field so far. In the next chapter, we will outline probable reasons and present emerging paradigm changes for the future research in microfluidics. 

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]. 

---