| Abstract
| - Polyamidoamine (PAMAM) dendrimers of different generations with various terminal groups were analyzed, forthe first time, using a combination of high-performanceliquid chromatography (HPLC), size exclusion chromatography (SEC), and matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) techniques. Separation of amine-terminated dendrimers from generation1 through generation 9 (G1NH2−G9NH2) was achievedusing reversed-phase HPLC with elution time increasinggradually as the density of terminal amine groups increases as a function of generation. Furthermore, separation of dendrimers with terminal amino, acetamide,hydroxyl, and carboxylate groups was obtained. It has alsobeen shown that HPLC can be used to separate dendrimers based on some structural defects inherent duringthe syntheses of PAMAM dendrimers. MALDI-TOF massspectra of G1NH2 identify the major imperfections presentduring typical synthesis processes. The absolute molarmasses (Mn) and molar mass distributions of the dendrimers were measured using the SEC system equippedwith multiangle laser light scattering and refractive-indexdetectors. Findings from this study suggest HPLC can bea vital tool for characterization and preparative separationof PAMAM dendrimers.
|
