Determining the content of organic substances in wood samples is currently associated with great analytical effort. The aim of this project was to develop quick and simple methods that should enable user e.g. to carry out a proof of quality of the impregnation directly on site. The method of the Enzyme Linked Immuno-Sorbent Assay (ELISA), developed in the project, which is based on antigen-antibody interactions, was expanded by the aptamer method during the course of the project. Short nucleic acid fragments in the Enzyme-Linked Apta-Sorbent Assay (ELASA) serve as recognition elements for target molecules.