Steven J. Geib

Bio: Steven J. Geib is an academic researcher from University of Pittsburgh. The author has contributed to research in topics: Hydrogen bond & Carbene. The author has an hindex of 48, co-authored 272 publications receiving 9771 citations. Previous affiliations of Steven J. Geib include Yale University & University of Delaware.

Cation-Triggered Drug Release from a Porous Zinc−Adeninate Metal−Organic Framework

Abstract: A porous anionic metal-organic framework, bio-MOF-1, constructed using adenine as a biomolecular building block is described. The porosity of this material is evaluated, its stability in biological buffers is studied, and its potential as a material for controlled drug release is investigated. Specifically, procainamide HCl is loaded into the pores of bio-MOF-1 using a simple cation exchange process. Exogenous cations from biological buffers are shown to affect the release of the adsorbed drug molecules.

High and Selective CO2 Uptake in a Cobalt Adeninate Metal−Organic Framework Exhibiting Pyrimidine- and Amino-Decorated Pores

Abstract: The synthesis and structure of Co2(ad)2(CO2CH3)2·2DMF·0.5H2O (bio-MOF-11) is described. Pyrimidine and amino groups of adeninate (ad) decorate the pores of the framework. The porosity of this material was studied, and its CO2 and H2 adsorption properties were evaluated. bio-MOF-11 exhibits a high heat of adsorption for CO2 (∼45 kJ/mol), a high CO2 capacity (∼6 mmol/g, 273 K), and exceptional selectivity for CO2 over N2 at 273 K (81:1) and 298 K (75:1).

Oligoanthranilamides. Non-Peptide Subunits That Show Formation of Specific Secondary Structure

Abstract: A family of novel oligomers based on the anthranilamide nucleus has been prepared and shown to form well-defined secondary structural features. 1H NMR and X-ray crystallographic techniques have demonstrated that intramolecular hydrogen bonds play a key role in stabilizing both linear sheet and helical conformational forms.

Lanthanide near infrared imaging in living cells with Yb3+ nano metal organic frameworks

Abstract: We have created unique near-infrared (NIR)–emitting nanoscale metal-organic frameworks (nano-MOFs) incorporating a high density of Yb3+ lanthanide cations and sensitizers derived from phenylene. We establish here that these nano-MOFs can be incorporated into living cells for NIR imaging. Specifically, we introduce bulk and nano-Yb-phenylenevinylenedicarboxylate-3 (nano-Yb-PVDC-3), a unique MOF based on a PVDC sensitizer-ligand and Yb3+ NIR-emitting lanthanide cations. This material has been structurally characterized, its stability in various media has been assessed, and its luminescent properties have been studied. We demonstrate that it is stable in certain specific biological media, does not photobleach, and has an IC50 of 100 μg/mL, which is sufficient to allow live cell imaging. Confocal microscopy and inductively coupled plasma measurements reveal that nano-Yb-PVDC-3 can be internalized by cells with a cytoplasmic localization. Despite its relatively low quantum yield, nano-Yb-PVDC-3 emits a sufficient number of photons per unit volume to serve as a NIR-emitting reporter for imaging living HeLa and NIH 3T3 cells. NIR microscopy allows for highly efficient discrimination between the nano-MOF emission signal and the cellular autofluorescence arising from biological material. This work represents a demonstration of the possibility of using NIR lanthanide emission for biological imaging applications in living cells with single-photon excitation.

Novel Folding Patterns in a Family of Oligoanthranilamides: Non-Peptide Oligomers That Form Extended Helical Secondary Structures

Abstract: Anthranilamide derivatives are used as the basis for a series of novel oligomers that fold into helical secondary structures in the solid state. When combined with pyridine-2,6-dicarboxylic acid and 4,6-dimethoxy-1,3-diaminobenzene subunits, oligoanthranilamides can be induced to take up a coiled conformation corresponding to two turns of a helix. X-ray crystallography shows that intramolecular hydrogen bonding and π−π stacking interactions are important in stabilizing the extended helical structures. Furthermore, both experimental and calculated 1H NMR methods indicate that related conformations are taken up by the oligomers in chloroform solution.

Carbon Dioxide Capture in Metal–Organic Frameworks

Abstract: Kenji Sumida, David L. Rogow, Jarad A. Mason, Thomas M. McDonald, Eric D. Bloch, Zoey R. Herm, Tae-Hyun Bae, Jeffrey R. Long

Chemical Redox Agents for Organometallic Chemistry

Abstract: 1. Advantages of Chemical Redox Agents 878 2. Disadvantages of Chemical Redox Agents 879 C. Potentials in Nonaqueous Solvents 879 D. Reversible vs Irreversible ET Reagents 879 E. Categorization of Reagent Strength 881 II. Oxidants 881 A. Inorganic 881 1. Metal and Metal Complex Oxidants 881 2. Main Group Oxidants 887 B. Organic 891 1. Radical Cations 891 2. Carbocations 893 3. Cyanocarbons and Related Electron-Rich Compounds 894

Metal-organic frameworks in biomedicine.

Abstract: Metal Organic Frameworks in Biomedicine Patricia Horcajada,* Ruxandra Gref, Tarek Baati, Phoebe K. Allan, Guillaume Maurin, Patrick Couvreur, G erard F erey, Russell E. Morris, and Christian Serre* Institut Lavoisier, UMR CNRS 8180, Universit e de Versailles St-Quentin en Yvelines, 45 Avenue des Etats-Unis, 78035 Versailles Cedex, France Facult e de Pharmacie, UMR CNRS 8612, Universit e Paris-Sud, 92296 Châtenay-Malabry Cedex, France Institut Charles Gerhardt Montpellier, UMR CNRS 5253, Universit e Montpellier 2, 34095 Montpellier cedex 05, France EaStChem School of Chemistry, University of St. Andrews Purdie Building, St Andrews, KY16 9ST U.K.