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101.
J. Billiter K. Bennewitz N. Bjerrum N. E. Loomis S. F. Acree C. N. Murray G. M. Kline M. R. Meacham Florence Fenwick Fr. L. Hahn M. Frommer I. Lifschitz M. Reggiani D. A. Mc Innes M. Dole C. W. Foulk M. Hollingsworth L. R. Parks H. C. Beard K. W. Franke J. J. Willaman Lava Hemedes H. T. S. Britton R. A. Robinson W. H. Harrison P. N. Vridhachalam J. J. Shukoff G. P. Awsejewitsch L. W. Elder Jr. P. Jolibois G. Fouretier P. Dubois H. A. Bromley L. W. Causer A. de Waele T. Callan S. Horrobin R. J. Fosbinder E. H. Ducloux 《Analytical and bioanalytical chemistry》1932,90(11-12):432-443
102.
A sensitive high-performance liquid chromatographic (HPLC) assay for the determination of the cyclic heptapeptide Ac-Cs-Asn-Dtc-Amf-Gly-Asp-Cys-OH (Dtc = beta,beta-dimethylthioproline, Amf = p-aminomethylphenylalanine) in human plasma has been developed. The key steps in the assay include: solid-phase extraction of the drug from plasma, chemical derivatization of the primary amino group with naphthalene-2,3-dicarboxyaldehyde in the presence of N-acetyl-D-penicillamine as a nucleophile to form a fluorescent benzo[f]isoindole derivative, and HPLC with column switching to provide the necessary chromatographic separation of the derivative from endogenous plasma components. The assay has been validated in the concentration range 1-10 ng/ml of plasma. 相似文献
103.
McElhanon JR Zifer T Kline SR Wheeler DR Loy DA Jamison GM Long TM Rahimian K Simmons BA 《Langmuir : the ACS journal of surfaces and colloids》2005,21(8):3259-3266
Two new surfactant molecules are reported that contain thermally labile Diels-Alder adducts connecting the hydrophilic and hydrophobic sections of each molecule. The two surfactants possess identical hydrophobic dodecyl tail segments but have phenol and carboxylic acid hydrophilic headgroups, respectively. Deprotonation with potassium hydroxide affords the formation of water-soluble surfactants. Room temperature aqueous solutions of both surfactants exhibit classical surface-active agent behavior similar to common analagous alkylaryl surfactant molecules. Critical micelle concentrations have been determined for each surfactant through dynamic surface tension and dye solubilization techniques. Small-angle neutron scattering measurements of the aqueous surfactant solutions indicate the presence of spherical micelles with radii of 16.5 angstroms for the carboxylate and 18.8 angstroms for the phenolate. When these surfactants are exposed to elevated temperatures (>50 degrees C), the retro Diels-Alder reaction occurs, yielding hydrophilic and hydrophobic fragments. Aqueous solutions of each surfactant subsequently exhibit a loss of all surface-active behavior and the micellar aggregates are no longer detectable. 相似文献
104.
A novel method for the determination of the relative stereochemistry of six-membered chairlike ring molecules by residual dipolar couplings is presented. C-H residual dipolar couplings were used to investigate the relative stereochemistry of 4,6-O-ethylidene-d-glucopyranose. For this and similar systems it is not necessary to acquire redundant dipolar couplings and to calculate the orientation order tensor. The presented methodology is a paradigmatic leap for the determination of the relative stereochemistry or remote stereochemistry in this kind of fused ring system. Residual dipolar coupling data were collected by 1D and 2D direct-measurement heteronuclear multiple quantum coherence (HMQC) spectroscopy. It was demonstrated that direct measurement of HMQC was quick and accurate for small molecules at natural abundance. 相似文献
105.
Sichinga Martin Chewe Kline Timothy Whitehead M. A. van de Ven Theo G. M. 《Cellulose (London, England)》2022,29(2):799-815
Cellulose - The quest to efficiently produce renewable and sustainable functional cellulosic products has prompted the development of an environmentally sensitive and cost-effective method to... 相似文献
106.
Bernier UR Allan SA Quinn BP Kline DL Barnard DR Clark GG 《Journal of separation science》2008,31(6-7):1092-1099
Candidate kairomones of ornithophilic mosquito species are reported from GC/MS analysis of compounds from the skin on the back, the feet, and feathers from the back of White Leghorn chickens (Gallus gallus domesticus). Hexane and ether extracts of chicken feathers differ significantly in attractiveness of Culex spp. mosquitoes. The active (hexane) extracts contained an abundance of alcohols, ketones, and diones. The inactive (ether) extracts contained aldehydes, which also were in the hexane extracts. Analysis of hexane extracts from chicken feet, skin, and feathers demonstrated the qualitative similarity in the compounds collected with subtle differences observed in the quantitative amounts of these compounds. Aldehydes and carboxylic acids were detected in a concentrated ether extract of feathers in quantitatively similar ratios within each compound class for the corresponding series of C(6)-C(9 )aldehydes and acids. 相似文献
107.
Kline TR Chen G Walker SL 《Langmuir : the ACS journal of surfaces and colloids》2008,24(17):9381-9385
This article describes a method to influence colloid deposition by varying the zeta potential at microelectrodes with remotely applied electric potentials. Deposition experiments were conducted in a parallel-plate flow chamber for bulk substrates of glass, indium tin oxide (ITO), and ITO-coated glass microelectrodes in 10 and 60 mM potassium chloride solutions. Colloid deposition was found to be a function of solution chemistry and the small locally delivered electric surface potentials. Electric fields and physical surface heterogeneity can be ruled out as cause of the observed deposition. Results are reported using experimentally determined Sherwood numbers and compared to the predictions of a previously developed patch model. Minor deviations between predicted and experimental Sherwood numbers imply that physical and chemical interactions occur. Specifically, we propose that colloidal particles respond to local variations in surface potential through electrostatic interactions, altering particle streamlines flowing along the surface and ultimately the extent of deposition. 相似文献
108.
109.
Kramer MA Andrews B Hugar DL Jaitli A Larsen SB Kline BP McEllen KN Agrawal N Su SM Dammu SA Kammeyer RM Ivanisevic A 《Langmuir : the ACS journal of surfaces and colloids》2010,26(23):18083-18088
Fourier transform infrared (FT-IR) spectroscopy is utilized to observe adsorbate interactions with a tissue-derived collagen scaffold extracted from the Bruch's membrane of pig eyes. The characterization includes conformational changes in isoleucine, polyisoleucine, collagen-binding peptide, RGD-tagged collagen-binding peptide, and laminin after adsorption onto the substrate. Isotopically labeled isoleucine is further utilized to understand changes in the biomolecular structure upon binding to a tissue-derived surface. The adsorbates associated with the collagen scaffold predominately through hydrophobic interactions and hydrogen bonding. The results of this study can be used to improve our understanding of surface chemistry changes during the engineering of biomimetic scaffolds before and after biomolecule adsorption. 相似文献
110.
Brian Drozdowski Yuhong Zhou Brad Kline Jared Spidel Yin Yin Chan Earl Albone Howard Turchin Qimin Chao Marianne Henry Jacqueline Balogach Eric Routhier Sina Bavari Nicholas C Nicolaides Philip M Sass Luigi Grasso 《Journal of immune based therapies and vaccines》2010,8(1):1-9