ON THE STRUCTURE OF POLYAMIDOAMINE DENDRIMER MONOLAYERS

Monolayers of polyamidoamine (PAMAM) dendrimers (generations 3.5 throu gh 10) are prepared via electrostatic self-assembling from water solut ions. Their thickness, morphology and mechanical stability are studied by scanning probe microscopy (SPM). A conformational state of dendrit ic macromolecules is discussed and compared to polymer scaling in the solution and recent molecular dynamics simulation results. The propose d model of molecular ordering assumes highly deformed (compressed alon g the surface normal) ellipsoidal shape for macromolecules in condense d monolayers. The molecular dimensions (thickness) versus molecular ma ss dependence is described by a scaling law with the exponent alpha = 0.28 being in-between values typical for dendrimer solutions and for a globular state. (C) 1998 Elsevier Science Ltd. All rights reserved.