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Cellulose carboxylate/tosylate mixed esters (Cel-Carboxy/Ts) were synthesized with constant degree of tosylation, DSTs=0.98 and variable degree of acylation, DSCarboxy; acetate, butanoate, and hexanoate. The tosylate (Cel-Ts) was prepared by reacting cellulose with tosyl chloride in presence of trimethylamine. The mixed esters were obtained by reacting Cel-Ts with carboxylic acid anhydride. The dependence of the following on DSCarboxy was investigated: IR data, including νCO, νSO and peak area (CO); empirical polarity of the films, determined by an adsorbed perichromic dye. We employed these parameters to determine DSCarboxy. Relative to ester saponification, these spectroscopic methods are convenient, expedient, and require much less sample. Mixed esters prepared physically from cellulose tosylate and tosylate/acetate behave only qualitatively similar to (Cel-Carboxy/Ts). The mixed esters were dissolved in acetone and regenerated in water as homogeneous microspheres.
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http://dx.doi.org/10.1016/j.carbpol.2016.06.075 | DOI Listing |
Anal Chim Acta
November 2025
Department of chemistry and Biochemistry, University of Texas at Arlington, Arlington, TX, USA. Electronic address:
Background: Carbonate esters are polar aprotic solvents that can be used to replace polar solvents: methanol, acetonitrile, or even apolar solvents in the mobile phases for liquid chromatography. Dimethyl, diethyl, and propylene carbonates (DMC, DEC, and PC) are not fully soluble in water.
Results: Twelve volume phase diagrams of water, the three carbonates, and methanol, ethanol, propanol, and acetonitrile were determined.
PeerJ
September 2025
School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, HI, United States of America.
Efficient detection and management of non-indigenous species are critical for mitigating their ecological impacts. Environmental DNA (eDNA) techniques have transformed biodiversity monitoring by enabling sensitive and cost-effective surveys. This study compares the efficacy of passive eDNA samplers (PEDS) to conventional active filtration methods for detecting the cryptogenic macroalga within the Papahānaumokuākea Marine National Monument, Hawai'i, USA.
View Article and Find Full Text PDFFood Sci Biotechnol
September 2025
Department of Food Science and Biotechnology, Seoul National University of Science and Technology, Seoul, 01811 Republic of Korea.
Unlabelled: This study examined how the ability to inhibit Ostwald ripening varies with ripening inhibitor type and how interfacial composition affects inhibitor efficiency. Emulsions were stabilized using Brij S100 and S20, which differ in ethylene oxide unit numbers, while medium-chain triglyceride (MCT) and ester gum (EG), possessing distinct molecular structures, were incorporated as ripening inhibitors. Ostwald ripening rate decreased with a higher proportion of Brij S20 at the interfacial membrane.
View Article and Find Full Text PDFSci Rep
September 2025
Department of Mechanical Engineering, Faculty of Engineering, Universitas Indonesia, Depok, 16424, Indonesia.
Synechococcus HS-9 is being recognized as one of the potential strains for biodiesel production due to its high levels of fatty acid methyl ester (FAME), which are around 70-78%. The first stage in producing microalgae biodiesel involves the biomass production process through a photobioreactor cultivation process. In addition to microalgae strains, the optimization of the photobioreactor's performance is essential for producing high biomass.
View Article and Find Full Text PDFJACS Au
August 2025
Institute of Precision Medicine (AUST-IPM), Anhui University of Science and Technology, Huainan, China.
The lack of safe and efficient delivery vectors remains a major bottleneck in nucleic acid therapeutics, limiting clinical translation. In this study, by incorporating the synergistic effects of guanidinium and tertiary amine functional groups, a new versatile branched poly-(β-amino ester) (PAE)-based delivery system was designed and developed, resulting in enhanced nucleic acid (DNA/mRNA) delivery. The synergistic interactions between these functional groups were systematically analyzed using 2D-NMR, AFM, TEM, and photophysical characterization.
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