title: New insights into silica-based NMR "chromatography".
abstract: Silica is used as an important component for NMR "chromatography". In this study the effect of the binding strength to silica of a variety of compounds on their diffusion rate is measured for the first time. Over two orders of magnitude of diffusion difference enhancement was obtained in the presence of silica for some compounds. An explanation of the enhancement is given that also allows one to predict the "chromatographic" behavior of new compounds or mixtures. The binding strength is divided into categories of weakly bound, singly bound and multiply bound. Carboxylates, sulfonates, and diols are found to be particularly strongly bound and to diffuse up to 2½ orders of magnitude more slowly in the presence of silica.
authors.affiliation: Casali Institute of Applied Chemistry, The Institute of Chemistry, Edmond J. Safra Campus, Givat Ram, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors.forename: Chava
authors.initials: C
authors.lastname: Pemberton
authors.forename: Roy
authors.initials: R
authors.lastname: Hoffman
authors.forename: Abraham
authors.initials: A
authors.lastname: Aserin
authors.forename: Nissim
authors.initials: N
authors.lastname: Garti
mesh_terms: D000588:Amines / Q000737:chemistry; D001557:Benzenesulfonates; D002725:Chloroform / Q000737:chemistry; D004058:Diffusion; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D009281:Naphthalenes; D000442:Octanols; D009930:Organic Chemicals; D012822:Silicon Dioxide
chemical_list: D000588:Amines; D001557:Benzenesulfonates; D009281:Naphthalenes; D000442:Octanols; D009930:Organic Chemicals; C535047:1,2-octanediol; C031721:naphthalene; C001114:dodecylbenzenesulfonic acid; D012822:Silicon Dioxide; D002725:Chloroform