Search results for "Dispersity"
showing 10 items of 207 documents
A new method for measurements of insoluble submicron particles in water
1991
Abstract A new method was developed to determine the size distribution of insoluble particles in e.g., fog water in the particle size range 50 nm p nm. First the water was nebulized and than the droplets dried to form residual aerosol particles. Using a Tandem Differential Mobility Analyser (TDMA), soluble and insoluble particles were separated. The system was calibrated with monodisperse latex particles to determine the loss factor for insoluble particles.
Über die bestimmung der strömungsdispersion zur ermittlung von molekulargewichtsverteilungen mit der gelchromatographie
1974
Die Kenntnis der axialen Dispersion ist eine notwendige Voraussetzung zur Ermittlung von Molekulargewichtsverteilungen aus der gelchromatographischen Elutionskurve. Die vorliegende Arbeit beschaftigt sich mit der Bestimmung der axialen Dispersion unter Verwendung monodisperser Polymerer. Abschliesend wird ein Verfahren vorgeschlagen, welches aus der gelchromatographischen Elutionskurve von Proben mit bekannter Molekulargewichtsverteilung die Dispersion naherungsweise zu ermitteln gestattet. The knowledge of the axial dispersion is necessary for the determination of molecular weight distributions from gel permeation chromatography elution diagrams. This work deal with the determination of th…
PeptoSomes for Vaccination: Combining Antigen and Adjuvant in Polypept(o)ide-Based Polymersomes.
2017
In this work, the first vaccine is reported based on a PeptoSome, which contains a model antigen (SIINFEKL) and adjuvant (CpG). PeptoSomes are polypept(o)ide-based polymersomes built of a block-copolymer with polysarcosine (PSar) as the hydrophilic block (X n = 111) and poly(benzyl-glutamic acid) (PGlu(OBn)) as the hydrophobic one (X n = 46). The polypept(o)ide is obtained with low dispersity index of 1.32 by controlled ring-opening polymerization. Vesicle formation by dual centrifugation technique allows for loading of vesicles up to 40 mol%. PeptoSomes are characterized by multiangle dynamic light scattering, static light scattering, and cryogenic transmission electron microscopy (cryoTEM…
Size-isolation of superparamagnetic iron oxide nanoparticles improves MRI, MPI and hyperthermia performance.
2020
Journal of nanobiotechnology 18, 22 (2020). doi:10.1186/s12951-020-0580-1
2-(1-Aryliminoethyl)-9-arylimino-5,6,7,8- tetrahydrocycloheptapyridyl iron(II) dichloride: synthesis, characterization, and the highly active and tun…
2014
A series of 2-(1-arylimino)ethyl-9-arylimino-5,6,7,8-tetrahydrocycloheptapyridine derivatives was synthesized and fully characterized, and thereafter reacted with iron dichloride to form their corresponding iron(II) complexes. The single crystals of representative organic and iron complex compounds were obtained and analyzed by the X-ray diffraction analysis, indicating the distorted bipyramidal geometry around the iron core. Moreover, DFT calculations were performed on selected species to determine their structural features. On treatment with either MAO or MMAO, all iron complex pre-catalysts showed high activities (up to 1.56 × 10(7) gPE mol(-1)(Fe) h(-1)) toward ethylene polymerization. …
Ethylene polymerization by the thermally unique 1-[2-(bis(4-fluoro phenyl)methyl)-4,6- dimethylphenylimino]-2-aryliminoacenaphthylnickel precursors
2015
A series of 1-[2-(bis(4-fluorophenyl)methyl)-4,6-dimethylphenylimino]-2-aryliminoacenaphthylene derivatives together with the corresponding nickel bromide complexes was synthesized and characterized. Representative complexes C2 and C5 were characterized by the single-crystal X-ray diffraction, revealing a distorted tetrahedral geometry. Upon activation with either methylaluminoxane (MAO) or ethylaluminum sesquichloride (EASC), all nickel complexes exhibited high activities towards ethylene polymerization, producing polyethylene with a relatively low degree of branching and narrow polydispersity. Complex C1 maintained good activity at elevated reaction temperatures, which indicates significa…
Estimation of the size of liposomes by modified HDC
1991
Internal calibration in modified hydrodynamic chromatography has been realized by the approach of Prieve and Hoysan, i.e. the use of polystyrene monodisperse latexes to evaluate the equivalent capillary radius, R. The value obtained has been used to estimate the average sizes of a variety of liposome samples from egg yolk lecithin.
Polymer-liposome nanoparticles obtained by the electrostatic bio-adsorption of natural polymers onto soybean lecithin liposomes
2012
This work is focused on the formulation of polymer-liposome nanoparticles based on the electrostatic bio-adsorption of natural polymers onto soybean lecithin liposomes, with potential as novel delivery system for macromolecules, such as proteins. The building up of the polymer-liposome nanoparticles was achieved through the alternating bio-adsorption of natural cationic (chitosan) and neutral (dextran) or anionic (dextran sulphate or alginate) polymer layers on a core composed by anionic nanosized soybean lecithin liposomes. The electrostatic bio-adsorption of natural polymers succeeded in building nanosized, spherical, monodisperse and stable polymer-liposome nanoparticles with cumulative …
Poly(ethylene glycol-co-allyl glycidyl ether)s: a PEG-based modular synthetic platform for multiple bioconjugation.
2011
A series of random copolymers comprising ethylene oxide (EO) and 0-100% allyl glycidyl ether (AGE) has been prepared by anionic ring-opening polymerization with molecular weights between 5000 and 13,600 g/mol and polydispersity indices in the range of 1.04-1.19. As key for the homogeneity of the PEG conjugates, real-time ¹H NMR polymerization kinetics, ¹³C NMR analysis of triad sequence distribution, and analysis of the thermal behavior by differential scanning calorimetry (DSC) revealed a distinctive random copolymer structure. Via thiol-ene coupling (TEC), showing mainly "click" characteristics and nearly quantitative yields, PEG derivatives with multiple amino, carboxy, or hydroxy functi…