Ultrasonic degradation of polyvinyl alcohol (PVA) was carried out in aqueous solution at 25 degrees C. In this experiment, the effect of solution concentration on the rate of degradation was investigated. Kinetics of degradation was studied by viscometry method. The calculated rate constants indicate that degradation rate of PVA solutions decreases with increasing of solution concentration (C= g lit(-1)). The calculated rate constants correlated in terms of reverse concentration and relative viscosity of PVA solutions. This behavior in the rate of degradation was interpreted in terms of viscosity and concentration of polymer solution. With increasing solution concentration, viscosity increases and it causes a reduction in the cavitation efficiency thus, the rate of degradation will be decreased.
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http://dx.doi.org/10.1016/S1350-4177(03)00110-X | DOI Listing |
Front Biosci (Landmark Ed)
January 2025
Department of Food Biotechnology and Microbiology, Institute of Food Sciences, Warsaw University of Life Sciences - SGGW, 02-776 Warsaw, Poland.
Background: This study investigated the selenium-binding capacity of the biomass of two yeast strains, American Type Culture Collection (ATCC) 7090 and CCY 20-2-26.
Methods: The studies carried out methods of bioaccumulation by yeast biomass. Inorganic selenium was added to the culture media as an aqueous solution of NaSeO at concentrations ranging from 0 to 40 mg Se/L.
Pharmaceutics
January 2025
Faculty of Pharmacy, "Grigore. T. Popa" University of Medicine and Pharmacy, 700115 Iasi, Romania.
Magnolol (MG) and honokiol (HK) are bioactive compounds extracted from and trees with significant pharmacological properties, including antioxidant and antibacterial activity. However, their poor water solubility and low bioavailability limit the therapeutic potential. To address these limitations, this study aims to develop MG and HK formulations by co-electrospinning using custom-synthesized β-cyclodextrin-oligolactide (β-CDLA) derivatives.
View Article and Find Full Text PDFPharmaceutics
January 2025
Programa de Posgrado en Odontología, Universidad de Costa Rica, Ciudad Universitaria Rodrigo Facio, San Jose 11501-2060, Costa Rica.
Objectives: This study aimed to synthesize polylactic acid (PLA) nanofibrillar scaffolds loaded with ibuprofen (IBU) using electrospinning (ES) and air-jet spinning (AJS). The scaffolds were evaluated for their physicochemical properties, drug release profiles, and biocompatibility to assess their potential for local analgesic applications.
Methods: Solutions of 10% (/) PLA combined with IBU at concentrations of 10%, 20%, and 30% were processed into nanofibrillar membranes using ES and AJS.
Pharmaceutics
January 2025
Laboratory of Biointerface Chemistry, Department of Molecules and Materials, Faculty of Science and Technology, Technical Medical Centre and MESA+ Institute, University of Twente, 7522NB Enschede, The Netherlands.
Hydrophobic microparticles are one of the most versatile structures in drug delivery and tissue engineering. These constructs offer a protective environment for hydrophobic or water-sensitive compounds (e.g.
View Article and Find Full Text PDFPlants (Basel)
January 2025
Department of Plant Physiology, Faculty of Biology, Sofia University, 8 Dragan Tsankov Bul., 1164 Sofia, Bulgaria.
Microalgae offer a promising alternative for heavy metal removal, and the search for highly efficient strains is ongoing. This study investigated the potential of two microalgae, sp. BGV (Chlorophyta) and Schwabe & Simonsen (Cyanoprokaryota), to bind zinc ions (Zn⁺) and protect higher plants.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!