CELLULAR & MOLECULAR BIOLOGY LETTERS Volume 7, (2002) pp 1087 – 1094 http://www.cmbl.org.pl Received 23 July 2002 Accepted 27 November 2002 Short Communication THE INTERACTION OF TRYPTOPHAN AND ANS WITH PAMAM DENDRIMERS BARBARA KLAJNERT and MARIA BRYSZEWSKA * Department of General Biophysics, University of Łódź, Banacha 12/16, 90-237 Łódź, Poland Abstract: Dendrimers are globular, hyperbranched polymers possessing a high concentration of surface functional groups and internal cavities. These unique features make them very useful in many biomedical applications, especially as carrier molecules. In this study, the interaction of tryptophan and 1- anilinonaphthalene-8-sulfonic acid with three types of polyamidoamine dendrimers was examined. It was observed that the type of dendrimer surface group has a strong impact on the interactions between the dendrimers and fluorescent molecules. Key Words: PAMAM Dendrimers, ANS, Tryptophan, Fluorescence INTRODUCTION Dendrimers are a relatively new class of polymeric material. They were discovered in the early 1980’s by Donald Tomalia and co-workers [1]. Dendrimers have a specific, well-defined structure. They are synthesised from a polyfunctional core by adding branched monomers that react with the functional groups of the core molecule, in turn leaving end groups that can react again. The number of reactive terminal groups increases after the addition of the layer of monomers. The more layers of branched units that are attached, the higher the level of dendrimer generation (Fig. 1). Because of their unique molecular architecture and globular shape, dendrimers show some interesting properties when compared to traditional linear polymers. * Corresponding author, E-mail: marbrys@biol.uni.lodz.pl Abbreviations: ANS: 1-anilinonaphthalene-8-sulfonic acid, Gn: n th generation of dendrimer, PAMAM: polyamidoamine, PBS: phosphate-buffered saline