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The half-generation poly(amidoamine) starburst dendrimers (SBD) resemble the external structure of anionic micelles and internal structure of biomacromolecules. The hydrophilic and hydrophobic binding sites of the SBD structure are probed by positively charged nitroxide radicals linked to carbon chains of varying lengths. The mobility and the polarity parameters are measured by computer-aided analysis of the interacting radicals' electron paramagnetic resonance spectra. The theory suggesting interaction of the radical chain with the hydrophobic sites is supported by the observations.

Electron paramagnetic resonance analysis of the structure of Cu(II) complexes developed with anionic starburst dendrimers in aqueous solution confirms a shift in dendrimer shape between previous and subsequent generations. Enhanced mobility of copper complexes is evident in previous generations. At low pH, copper ions form monomeric carboxylate complexes.

Interactions of the family of polypyridyl metal complexes with B-DNA were studied using Ru(phen)2(phen-T)Cl2 and Ru(bpy)2(phen-T)Cl2, the two polypyridyl complexes of ruthenium(II). Surface and intercalative binding with DNA are evident. The phenanthroline unit, which has been altered with the nitroxide, is not part of the intercalative pattern of binding.

Direct evidence is provided for validating the model for the external surface of zeolite by Fourier transform infrared (FT-IR) spectroscopy and a new method is developed for 'titrating' the strong binding sites by EPR spectroscopy. The analysis has provided insights into a displacement mechanism caused by spectator molecules and has shown how the product distribution of photolysis of sorbed ketones can be controlled.

The electron spin-spin superexchange between an incarcerated paramagnetic nitroxide molecule and a nitroxide molecule present in the external aqueous phase is demonstrated by NMR and EPR spectroscopy. The results show that the spin-spin interactions could be enhanced by supramolecular binding resulting from Coulombic attractions or inhibited via Coulombic repulsions.

The photolysis of 1,1,3,3-tetraphenylacetone that is adsorbed on a MFI zeolite, the sodium form of LZ-105, yields diphenylmethyl (DPM) radicals. The DPM radicals are supramolecularly persistent and react reversibly with oxygen. The reversible oxygenation reaction is established at room temperature and is similar to the behavior of triphenylmethyl radical produced in a solid glass lattice.

The supramolecular structure and dynamics of molecules and reactive radicals on MFI zeolites were studied using photochemical and magnetic resonance investigations.

Presents a study of half-generation starburst dendrimers (SBD) using electron paramagnetic resonance spectroscopy (EPR). Localization of the radical probes; Difference between anionic micelles and n.5-SBDs; Hydrophobic interactions between the carbon chain of the radicals and sites at low polarity in the internal SBD structure; Dendrimer morphology.

Investigates the structure of Cu(II) complexes formed with anionic starburst dendrimers in aqueous solution. Use of the electron paramagnetic resonance (EPR) technique; Line shapes of the EPR spectra of the complexes; Magnetic parameters; Evaluation of Cu(II) bonding parameters; Covalency of in-plane bonds.