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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Multiphase biochemistry : Liquid membranes and the affinity chromatography of oxygenases

Landgraff, Laura Mastrogianni 05 1900 (has links)
No description available.
32

A capillary-based microfluidic system for immunoaffinity separations in biological matrices

Peoples, Michael Chad, January 1900 (has links)
Thesis (Ph.D.)--Virginia Commonwealth University, 2008. / Title from title-page of electronic thesis. Prepared for: Dept. of Pharmaceutics. Bibliography: leaves 149-166.
33

The Coldwell Alkaline Complex, Ontario: Magmatic Affinity as Determined by an Isotopic and Geochemical Study

Bohay, Trevor 05 1900 (has links)
<p> The Proterozoic' Coldwell Alkaline Complex is the southernmost intrusion of a number of N -S trending igneous bodies occurring in the Midcontinental Rift system exposed in the Lake Superior area. The Coldwell complex is host to several Ni-Cu-PGEbearing intrusions two of which; the Two-Duck Lake intrusion (Marathon deposit) and the Geordie Lake gabbro (MacRae occurrence) have been investigated in some detail with respect to PGE mineralisation. Both of these have been suggested to have experienced crustal contamination in conjunction with mineralisation. As a test of this possibility, a detailed Sm-Nd, oxygen isotope, and whole-rock geochemical study of these mineralised occurrences as well as of the Dunlop occurrence and the Middleton occurrence, together with unmineralised rocks of the complex was undertaken. The primary objectives are to determine whether crustal contamination is indicated in mineralised rocks and to try and ascertain the nature of the magma which formed the complex. </p> <p> The Coldwell complex is thought to have been formed by emplacement of magma at three intrusive centres. Sm-Nd data for rocks from these three centres reveal similar isotopic values, with slight variations; samples taken from the western gabbros exhibit eNd values averaging -0.9 ranging from -2.9 to 0.9, whereas rocks from the eastern margin and centre of the complex have eNd values of about an average of 0.5 ranging from -0.5 to 1.2 suggesting that the magma that formed these rocks has undergone a lesser degree of crustal contamination. This data, supported by oxygen isotope and wholerock geochemical information indicates that crustal contamination seems to play a small, and varied role in the genesis of the Coldwell magmas. The Nd isotope data all clusters at values for CHUR, which indicates that it has been enriched relative to the depleted mantle. It has been postulated that an enriched mantle plume resided under the rift and promoted rift-related magmatism. The data from this study would seem to support this supposition. </p> <p> Geochemical parameters utilised to define fields to geochemically delineate possible end member contributors to this primarily plume-derived magma indicate, that in addition to small, variable amounts of assimilation of upper and lower crust, the plume magmas also interacted with the lithospheric upper mantle to a small degree. </p> / Thesis / Master of Science (MSc)
34

Antibody Purification from Tobacco by Protein A Affinity Chromatography

Hey, Carolyn McKenzie 07 June 2010 (has links)
Antibodies represent the largest group of biopharmaceuticals. Due to the nature of their clinical applications, they often need to be produced in large quantities. Plants have distinct advantages of producing large quantities of recombinant proteins, and tobacco is arguably the most promising plant for plant-made-pharmaceuticals (PMP) due to its high biomass yields and robust transformation technology. However, to produce proteins using transgenic tobacco for human applications, purification of the proteins is challenging. On the other hand, Protein A, a bacterial cell wall protein isolated from Staphylococcus aureus that binds to the Fc regions of immunoglobulins, is useful to the isolation and purification of antibodies. An affinity chromatography purification step utilizing Protein A resin introduced early in the purification process can reduce successive unit operations, thereby reducing the overall process cost. However, directly applying tobacco extract to Protein A chromatography columns may be problematic due to the non-specific binding of native tobacco proteins (NTP). In this project, three different Protein A resins, ProSepvA High Capacity, ProSep-vA Ultra, and ProSep Ultra Plus, marketed by Millipore, were studied to provide valuable information for future downstream processes for antibody purification from transgenic tobacco. The efficiency of the post load wash buffer to reduce non-specific binding of NTP to the ProSep A resins were evaluated by altering the ionic strength and pH. Lower salt concentrations of sodium chloride (NaCl) in the post load wash preformed best at reducing the non-specific binding of NTP to the ProSep A resins, while higher salt concentrations were more effective at reducing the amount of NTP contaminants present during elution of the columns. Using a post load wash buffer with an intermediate pH between the binding buffer and the elution buffer was more efficient at eluting our model antibody, human IgG. However, lowering the ionic strength and the pH of the post load wash buffer resulted in a greater presence of IgG prematurely eluting from the ProSep A resins. The non-specific binding of NTP to the resins reduced the dynamic binding capacity (DBC) of the resins after repeated cycles of tobacco extract samples were loaded onto the column. Nevertheless, cleaning the columns with denaturing solutions, such as urea or guanidine hydrochloride, every 8-10 cycles was effective in regenerating the DBC of the resins and prolonging the life cycle of the resins. This is important to evaluating the economic feasibility of directly using Protein A chromatography to recover antibodies from tobacco extract. Of the three Protein A resins studied, ProSep Ultra Plus performed best for antibody purification from tobacco using a PBS wash buffer with a lower ionic strength of 140mM NaCl and an intermediate pH of 5. / Master of Science
35

DEVELOPMENT OF AFFINITY GRID MATERIALS FOR CRYOELCTRONIC MICROSCOPY

Md R Hoq (6617981) 12 October 2021 (has links)
<p>Cryogenic transmission electron microscopy (cryoEM) has become an increasingly common tool for determining structures of proteins and protein complex at near atomic resolution. We seek to determine the structure of p97 by cryoEM using an affinity capture approach that employs a family of novel synthetic lipids bearing water soluble PEG units and known high affinity inhibitor molecules at the distal end of the polymer. A library of inhibitor modified affinity lipopolymers of 5000 KD PEG molecular weights were synthesized. The inhibitor modified lipid coated grids were used to capture p97. The reconstruction of p97 revealed the structure at dimeric state at 3.64 Å and monomeric state at 4.33 Å. A PEG unit composed of 20000 KD molecular weight based polyrotaxane containing NTA ligand as affinity tag has been synthesized, used to concentrate 6x-his tagged p97 on TEM which also enabled to see all 3D orientation of the target particles and an initial model of 10.64 Å resolution of p97 structure was resolved. </p>
36

Analysis Of Protein Purification By Affinity Chromatography

Sridhar, P 05 1900 (has links) (PDF)
No description available.
37

Characterisation of the type I IGF receptor binding surfaces of insulin-like growth factor 1 using protein engineering

Marsh, Andrew January 1998 (has links)
No description available.
38

Diversity: Is it worth it?

jackson, Christopher 01 January 2017 (has links)
This paper takes a dive into understanding if funding extra diversity initiatives at Claremont McKenna College currently spurred on by students are worth the cost to the institution. Resources like that of Claremont McKenna’s C.A.R.E. Center (Civility, Access, Resources, and Expression) and funding for representative student organizations place large pressures on the institution’s available budget and there is not much proof that they will pay off in the long-run. In this paper, financial costs for supporting diverse students on campus are aggregated and compared to the possible financial benefits that may come of their consequential use. Results show that there is a largely positive societal benefit to the use of these resources at a fraction of the cost to the institution. These findings derive from CMC cost data; however, results imply similar conclusions across secondary education institutions nationwide.
39

STABILITY AND SPECTROSCOPIC PROPERTIES OF NEGATIVE IONS

Behera, Swayamprabha 06 May 2011 (has links)
Negative ions play an important role in chemistry as building blocks of salts and oxidizing agents. Halogen atoms, due to their ability to attract electrons, readily form negative ions. Considerable interest exists in the design and synthesis of new negative ions called superhaogens whose electron affinities are much higher than those of halogen atoms. This thesis deals with the design of such species. Using density functional theory I have studied two classes of superhalogens. First one involves d1 transition metal (Sc, Y, La) atoms surrounded by Cl while the second one involves simple metals (Na, Mg, Al) surrounded by pseudohalogens such as CN. Geometry, electronic structure, and electron affinity of these species containing up to 5 ligands have been calculated. Studies reveal a fundamental difference between the interaction of transition and metal atoms with electronegative ligands. In addition, pseudohalogens can be used to synthesize a new class of superhalogens.
40

Saccharide sensing by affinity mass sensors.

January 1999 (has links)
by Lee Tin-wan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 79-84). / Abstracts in English and Chinese. / Chapter 1. --- Introduction / Chapter 1.1 --- Chemical sensors --- p.1 / Chapter 1.2 --- Quartz crystal microbalance --- p.5 / Chapter 1.3 --- Film immobilization technologies --- p.11 / Chapter 1.4 --- Research Outlines --- p.13 / Chapter 2. --- Saccharide detection by affinity mass sensor / Chapter 2.1 --- Concept of affinity mass sensor --- p.15 / Chapter 2.1.1 --- Affinity chromatography --- p.15 / Chapter 2.1.2 --- Basis of affinity mass sensor --- p.17 / Chapter 2.1.3 --- Saccharide sensing --- p.19 / Chapter 2.2 --- Experimental --- p.20 / Chapter 2.2.1 --- Flow-through cell --- p.21 / Chapter 2.2.2 --- QCA 917 quartz crystal analyzer --- p.21 / Chapter 2.2.3 --- Experimental setup --- p.25 / Chapter 2.2.4 --- Sensor fabrication --- p.29 / Chapter 2.2.5 --- Analysis procedures --- p.29 / Chapter 2.3 --- Results and Discussion --- p.30 / Chapter 2.3.1 --- Formation of boronate complex --- p.30 / Chapter 2.3.2 --- Response curve --- p.31 / Chapter 2.3.3 --- Ligand (APBA) immobilization --- p.32 / Chapter 2.3.4 --- Effect of various operating parameters --- p.35 / Chapter 2.3.5 --- Calibration and reproducibility --- p.38 / Chapter 2.3.6 --- Kinetics analysis --- p.39 / Chapter 2.3.7 --- Stability of sensor --- p.44 / Chapter 2.3.8 --- Determination of fructose in real samples --- p.44 / Chapter 2.3.9 --- Comparison with conventional saccharides sensors --- p.46 / Chapter 2.4 --- Summary --- p.47 / Chapter 3. --- Sol-gel fabrication of affinity mass sensor / Chapter 3.1 --- Principle of sol-gel method --- p.48 / Chapter 3.2 --- Encapsulation of organic molecules in sol-gel matrices --- p.51 / Chapter 3.3 --- Experimental --- p.53 / Chapter 3.3.1 --- Preparation of alkoxide solutions --- p.53 / Chapter 3.3.2 --- Film deposition on QCM --- p.55 / Chapter 3.3.3 --- Film characterization and surface analysis --- p.56 / Chapter 3.4 --- Results and Discussion --- p.57 / Chapter 3.4.1 --- Optimization of conditions for sol-gel process --- p.57 / Chapter 3.4.1.1 --- Choice of catalyst --- p.57 / Chapter 3.4.1.2 --- "H2O: TEOS ratio, R" --- p.59 / Chapter 3.4.1.3 --- Ligand loading --- p.60 / Chapter 3.4.1.4 --- Surface active agent --- p.60 / Chapter 3.4.1.5 --- Temperature --- p.61 / Chapter 3.4.1.6 --- Ageing and drying --- p.62 / Chapter 3.4.2 --- Characterization of APBA encapsulated film --- p.62 / Chapter 3.4.3 --- Performance of the sol-gel derived sensor --- p.65 / Chapter 3.4.3.1 --- Calibration --- p.65 / Chapter 3.4.3.2 --- Stability --- p.66 / Chapter 3.4.3.3 --- Selectivity --- p.68 / Chapter 3.4.4 --- Applicability of the sol-gel derived sensor --- p.69 / Chapter 3.4.5 --- Comparison between sensors fabricated via crosslinking method and the sol-gel method --- p.70 / Chapter 3.4.5.1 --- Surface uniformity --- p.70 / Chapter 3.4.5.2 --- Reproducibility in mass deposition --- p.72 / Chapter 3.4.5.3 --- Stability --- p.72 / Chapter 3.4.5.4 --- Sensitivity towards fructose standard --- p.73 / Chapter 3.4.5.5 --- Comparison of precision and accuracy --- p.73 / Chapter 3.5 --- Summary --- p.75 / Conclusion --- p.77 / References --- p.79 / Titles for tables --- p.85 / Captions for figures --- p.86 / Appendix I --- p.88 / Appendix II --- p.89 / Appendix III --- p.95

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