Langmuir-Blodgett deposition method

Illustration showing the Langmuir-Blodgett method [54] of depositing organic films D = dipping, L = lifting... 

Szekeres et al. (2003) prepared monolayers of Stober silica particles on the surface of water and deposited onto glass substrates by the Langmuir-Blodgett method. Prior to film formatiou the surface of the silica particles was methoxylated by washing with methanol at room temperature. This reaction... 

Besides the electrochemical method, other methods such as the chemically initiated polymerization method, the vapor-phase methods, and the Langmuir-Blodgett method have been devised for the preparation of conducting polymers. In the chemical method, a chemical oxidant such as ferric chloride initiates the polymerization. Polymerization usually results in a powdery product and the resultant powder is then compressed into a pellet or dissolved in a suitable solvent such as methylene chloride or chloroform and spin coated on a substrate. In the vapor-phase technique, which is a variation of the chemical method, a monomer film is vacuum sublimed onto a glass substrate and then exposed to a solution or vapor of ferric chloride for oxidative polymerization. Films thus prepared are usually thick, of the order of micrometers. For some applications in which ultrathin and very uniform films are required, the Langmuir-Blodgelt technique for depositing monolayers has also been tried successfully [5]. 

D array formation by Langmuir-Blodgett method and deposition onto the substrate... 

The other method of monolayer transfer from the air/water interface onto solid substrates is illustrated in Figure 2. This method is called the Langmuir-Schaefer technique, or horizontal lift. It was developed in 1938 by I. Langmuir and V. Schaefer for deposition of protein layers. Prepared substrate horizontally touches the monolayer, and the layer transfers itself onto the substrate surface. The method is often used for the deposition of rigid monolayers and for protein monolayers, hi both cases the apphcation of the Lang-muir-Blodgett method produces defective films. 

The Langmuir-Blodgett deposition is one of the best methods to prepare highly organized molecular systems, in which various molecular parameters such as distance, orientation, extent of chromophore interaction, or redox potential can be controlled in each monolayer. We have been studying... 

An ordered antibody array has also been assembled on the solid surface by a combination of Langmuir Blodgett (LB) film method and self-assembling method. An ordered monolayer of protein A is deposited on the solid surface by LB method, which is followed by self-assembling of antibody. Individual antigen molecules which are complexed with the antibody array have been quantitated selectively by atomic force microscopy (AFM). 

Some decades ago (Langmuir, 1920), it was reported that, when a clean glass plate was dipped into water covered by a monolayer of oleic acid, an area of the monolayer equal to the area of the plate dipped was deposited on withdrawing the plate. Later, it was found that any number of layers could be deposited successively by repeated drippings, later called the Langmuir-Blodgett (LB) method (Petty, 1996 Roberts, 1990 Birdi, 1989). 

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