Conductive polymers, combinatorial synthesis

These conceptual goals are attained by several combinatorial methods and tools. Characteristic for combinatorial chemistry is the synthesis on solid support or by polymer-supported synthesis, allowing for much higher efficiency in library production. Synthesis can be conducted either in automated parallel synthesis or by split-and-recombine synthesis. Centerpieces of combinatorial methods further include specific analytical methods for combinatorial... 

Abstract Conductive polymers are established materials for development of chemical and biological sensors. Properties of these polymers are influenced by a number of different physical and chemical factors. Application of combinatorial and high-throughput techniques to development and optimization of chemo and biosensors is reviewed. Methods for addressable synthesis of conductive polymers and protocols for comprehensive description of chemosensitive properties are discussed. 

Experimental approaches to combinatorial synthesis of conductive polymers are summarized in the Fig. 13.2. Combinatorial polymerization driven by an introduced chemical oxidizer can be performed with a usual liquid handling robot or with a microfluidic system. Surprisingly, much more sophisticated techniques were usually used (Fig. 13.2). 

Fig. 13.2 Experimental approaches for combinatorial synthesis of conductive polymers. The figure includes a parts of illustration reprinted with permissions from Xiang and La Van39 (copyright 2006 The Institute of Electrical and Electronics Engineers, Inc.)...

The results demonstrate several approaches to combinatorial synthesis of conductive polymers and an example of automated high-throughput screening of their chemosensitive properties. Convenient format of combinatorial libraries in the form of small amounts of polymers (few Jg) deposited on silicon substrate with electrodes allows one not only simple characterization, but also simple storage and organization of banks of materials with electrical and optical access for further investigations. 

Mirsky, V. M. Kulikov, V. Wolfbeis, O. S. Complete system for combinatorial synthesis and functional investigation of conductive polymers. PMSE Preprints. 2005, 93, 1053... 

An extension of the combinatorial synthesis in solution is achieved by the use of soluble polymeric supports [80, 81], which combines some of the advantages of chemistry in solution and on solid phase. The so-called liquid-phase combinatorial synthesis is based on the physical properties of poly (ethylene glycol) monomethyl ether. The polymer is soluble in a variety of aqueous and organic solvents, which allows reactions to be conducted in homogeneous phase whereas the propensity to crystallize in appropriate solvents facilitates the isolation and purification of the compound at each step of the combinatorial synthesis. 

Introduced in the early 1990s, the split-and-recombine concept contributed much to the early success of combinatorial chemistry. Often, all combinatorial methods were identified with this concept. Split-and-recombine synthesis offered easy access to large number of individual compounds in few steps. If conducted on polymer beads, these are easily separated mechanically and can be identified subsequent to a screening step. 

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