Search results for "Cellulose acetate"
showing 7 items of 7 documents
Multicomponent solid dispersion as a formulation strategy to improve drug permeation: A case study on the anti-colorectal cancer irinotecan
2019
Abstract Multicomponent solid dispersions (MSD)s are frequently proposed as efficient drug delivery systems to improve drug solubility and bioavailability. In this study, the effects of specific excipients, such as mannitol, inulin, poly(methyl methacrylate-co-methacrylic)acid (PMMA) and cellulose acetate phthalate (CAP) have been tested to potentially improve irinotecan (IRN) permeation in the intestinal tract with the intention to protect the drug from the gastric environment. MSDs were formulated as microparticles by Spray-Drying technique. Raw materials and microparticles have been characterized by FTIR analysis to determine hydrogen bonding. SEM images were recorded to investigate morp…
Nachweis von fetalem H�moglobin in Blutspuren mit Hilfe der Celluloseacetatfolien- (CAF) -Elektrophorese
1977
Blutspuren von 160 Nabelvenenblutproben wurden elektrophoretisch nach der von Wraxall beschriebenen Technik aufgetrennt und konnten gut drei Monate lang nach Lagerung bei Zimmertemperatur von Erwachsenenblutspuren unterschieden werden. Unterschiedliche Spurentrager (Glas, Holz, Filterpapier und Leinen) hatten keinen nennenswerten Einflus auf die Darstellung.
Effective Degradation of Cigarette Butts via Treatment with Old Landfill Leachates
2021
In this paper, results of feasibility study on microplastics (MPs) assessment in leachates from the Latvian solid municipal landfill Getliņi are discussed. The application of leachates for the treatment of cigarette butts (CGB) was evaluated. Methods of fluorescent microscopy, Fourier transform infrared (FTIR) spectroscopy and FTIR-microscopy were used for the identification and characterization of MPs in the leachates and analysis of CGB. Presence of the secondary MPs (e.g., degraded polyolefin mixtures) was determined in the tested landfill leachates, while cellulose acetate (CA) was not determined in these products. The leachates were tested as potential media for the thermophilic (55°C)…
Fractionation of cellulose acetate for the investigation of molecular weight influences on the morphology of membranes
2003
Abstract Cellulose acetate (CA) with an apparent weight average molar mass, M w ∗ , of 150 kg/mol was fractionated with respect to M by means of the mixed solvent methyl acetate (MeAc)/2-propanol (2-POH) applying a new method that uses spinning nozzles to promote the rapid attainment of phase equilibria. Two of the fractions obtained in this manner were employed to prepare membranes from solutions in methyl acetate with 2-propanol as coagulating agent. Electron micrographs demonstrate that the molar mass of CA influences the morphology of the membranes markedly under otherwise identical conditions. For M w ∗ =128 kg/mol, one obtains considerably denser structures than for M w ∗ =263 kg/mo…
ZnO/polyaniline composite based photoluminescence sensor for the determination of acetic acid vapor
2020
In this study, we report a novel ZnO/polyaniline (PANI) nanocomposite optical gas sensor for the determination of acetic acid at room temperatures. ZnO nanorods, synthesized in powder form were coated by PANI (ZnO/ PANI) by chemical polymerization method. The obtained nanocomposites were deposited on glass substrate and dried overnight at room temperature. Structure and optical properties of ZnO/PANI nanocomposite have been studied by using X-ray diffraction, transmission electron microscopy, scanning electron microscopy, diffuse reflectance and photoluminescence spectroscopy. Tests towards acetic acids were performed in the range of concentrations 1–13 ppm. The adsorption of acetic a…
Formation of micro- and nano-spheric particles (filter dust) during the preparation of cellulose acetate membranes
2003
Abstract Membranes were prepared from six samples of cellulose acetate (CA) differing in their average molecular weight (75–260 kg/mole) and molecular weight distribution using methyl acetate as solvent and 2-propanole as precipitant. The routes through the phase diagram and the evaporation times were varied in these experiments. Electron microscopy demonstrates that the amount of filter dust (CA particles deposited on the membrane surface) decreases as the fraction of low molecular weight material in the starting polymer becomes less. For low average molar mass of CA and moderate polymer concentrations in the casting solution the dust consists of individual spheres of relatively uniform si…
Muscle adenylate kinase in Duchenne muscular dystrophy
1986
Abstract On the basis of electrophoretic and enzyme inhibition studies it was postulated that an aberrant adenylate kinase occurs in muscle and serum of patients with Duchenne muscular dystrophy (Schirmer, R.H. and Thuma, E. (1972) Biochim. Biophys. Acta 268, 92–97; Hamada, M. et al. (1981) Biochim. Biophys. Acta 660, 227–237; Hamada et al. (1985) J. Biol. Chem. 260, 11595–11602. On the basis of the following results we conclude that Duchenne muscular dystrophy patients do not possess an unusual adenylate kinase isoenzyme. (1) In muscle biopsies from five Duchenne patients, the electrophoretic mobility of adenylate kinase and the inhibition of the enzyme by P 1 , P 5 -di(adenosine-5′)pentap…