Holger Dipl Chem Dr Ohst

An optical biosensor principle based on fluorescence energy transfer

Abstract The specific binding of a fluorescence-labelled mannoside to immobilized concanavalin A is detected by Forster energy transfer, where the donor fluorophore is polymer-bound in a Langmuir-Blodgett film. The applicability of this method to biosensing is discussed.

Polyesters and polyurethanes as prepolymerized materials for Langmuir-Blodgett films: Preparation and characterization of multilayers

Abstract Two new types of amphiphilic polymers, namely polyesters and polyurethanes, capable of forming monolayers at an air-water interface were synthesized. The polyesters were obtained by the condensation of both long-chain substituted diols and diesters with available materials. The amphiphilic polyurethanes were prepared by polyaddition of long-chain diols and common diisocyanates. Pressure-area isotherms show the formation of a more-or-less liquid- analogous state. Y-mode Langmuir-Blodgett multilayers of these preformed polymers can be transferred to rigid substrates with a constant transfer ratio. In polyester and polyurethane multilayers, the aliphatic side-chains are perpendicular to the film as evidenced by ellipsometric and X-ray measurements of film thickness and orientation.