Combinatorial polyelectrolyte multilayer film fabrication

J Nanosci Nanotechnol. 2009 Nov;9(11):6421-6. doi: 10.1166/jnn.2009.1469.

Abstract

A combinatorial strategy for the fabrication of a library of polyelectrolyte multilayer films is presented in this paper. This innovative approach involves the parallel formation of polyelectrolyte multilayer films in the individual wells of polystyrene microtitre plates under various deposition conditions. The progress of film formation was monitored via the intensity of the UV-vis absorbance of one of the depositing polyelectrolytes using a conventional microplate reader. We demonstrate the utility of this technique by building a library of 120 distinct polyelectrolyte multilayer films. Both the primer layer composition and salt content of the polyeletrolyte solutions were systematically varied in the preparation of films of nine bilayers. Film growth did not follow a linear adsorption regime for the first three bilayers regardless of the composition of the primer layer. We observed that increasing the sodium chloride concentration in the polyelectrolyte solutions resulted in increased polyelectrolyte absorption for all the conditions studied. The approach presented here is a convenient method of producing and characterizing multiple films rapidly and reproducibly, making it a valuable tool for optimizing film fabrication.