Microfluidic Systems for Combinatorial

Fig. 13.3 Design of microfluidic system for combinatorial electrochemical synthesis of conductive polymers. The device is composed of a gradient generator and a parallel electrochemical synthesis reactor. Two different species A and B were injected into the system from the top. Reprinted with permission from Xiang and La Van39 (copyright 2006 The Institute of Electrical and Electronics Engineers, Inc.)...

Microfluidic systems for combinatorial chemistry are used to discover and optimise the chemical reactions used to produce novel materials, in particular catalysts and drugs. They may also be used to optimise the reaction conditions. The systems are designed to perform a large number of reactions in parallel, each differing - usually only a little - in some variable (or variables), like presence of reagents, their mixing ratio, composition of catalysts, etc., while other variables are kept invariant. The test results, such as properties of the reaction products, are evaluated and stored in the form of combinatorial libraries. Information extracted from the libraries is used to identify optimum reaction conditions. 

Microfluidic Systems for Combinatorial Chemistry, Rgure 1 The task of the sampling unif in principle is a conversion of the spatial distribution of the samples (each available at a different location) into the temporal distribution admitted into the measurement device... 

Microfluidic Systems for Combinatorial Chemistry, Figure 2 Schematic of the sampling unit consisting of an array of controlled valves and a junction circuit... 

Microfluidic Systems for Combinatorial Chemistry, Figure 6 Schematic representation of the microfluidic circuit using an array of the valves from Fig. 3, to control the sample flows and the junction circuits. Basically similar to the layout from Fig. 5, this circuit has a more complicated way of leading the fluids into the vent. Arrows indicate the protective flows... 

Microfluidic Systems for Combinatorial Chemistry, Figure 10 A sampling unit with 16 valves in the version from Fig. 9. This example of a microfluidic integrated circuit was made by etching in stainless steel [12]... 

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