Authors: K. Pasupathy, A.T. Jones and P.C. Ke
Affilation: Clemson University, United States
Pages: 283 - 286
Keywords: PAMAM, hydrocarbon, TIRF
Dendrimers are star-branched polymers which have broad applications from energy harvesting, catalysis, drug delivery, to gas-hydrate prevention in the petroleum industry. However the underlining mechanisms of these applications are not well understood. Here we present our absorption spectrophotometry and Total Internal Reflection Fluorescence (TIRF) microscopy of the interaction between G3-PAMAM (Generation 3 PolyAmidoAmine) dendrimers and hydrocarbons (Squalane) at the single-molecule level. Using spectrophotometry we show that the mixing of Squalane with G3-PAMAM induces the enhancement of PAMAM absorption peak at 506 nm, suggesting that the hydrocarbons are adsorbed by PAMAM through hydrophobic interactions. Using TIRF we show rhodamine labeled PAMAM molecules are immobilized onto a glass substrate pre-coated with Squalane. These studies are extended using Transmission Electron Microscopy (TEM) to image PAMAM-Squalane complexes. Our studies suggest that the morphology of dendrimers significantly promotes the adsorption of hydrocarbons through hydrophobic-hydrophobic interactions, thus shielding them from exposure to water that induces gas hydrates.