The esterification of ethylene glycol with propionic acid was investigated in supercritical CO2 at 50.0 degrees C. The effect of pressure on equilibrium conversion and selectivity of ethylene glycol monopropionate (monoester) and ethylene glycol dipropinonate (diester) was studied systematically. It was shown that the equilibrium conversion and selectivity was nearly independent of pressure as pressure was lower than 9 MPa. At higher pressure, however, the yield and selectivity of the diester increased considerably, while those of the monoester decreased with increasing pressure. The main reason was that reactants and products distributed between the vapor phase and liquid phase at higher pressures. The solvent power of CO2 for the diester is stronger than that for the monoester. More diester molecules in the liquid phase were extracted into the vapor at higher pressures, which shifted equilibrium of the consecutive reversible reactions.
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ACS Appl Mater Interfaces
January 2025
Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill 27599, United States.
Architecturally hindered crystallization of bottlebrush graft copolymers offers a reaction- and solvent-free pathway for creating injectable elastomers with tissue-mimetic softness. Currently, injectable materials involve solvents and chemical reactions, leading to uncontrolled swelling, leaching of unreacted moieties, and side reactions with tissue. To address this issue, bottlebrush copolymers with a poly(ethylene glycol) (PEG) amorphous block and crystallizable poly(lactic acid) (PLA) grafted chains (A--B) were synthesized, with grafted chains of controlled length arranged along the backbone at controlled spacing.
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January 2025
Max Bergmann Center of Biomaterials Dresden, Leibniz-Institut für Polymerforschung Dresden e. V., Hohe Str. 6, 01069, Dresden, Germany.
Cell-instructive polymer hydrogels are instrumental in tissue engineering for regenerative therapies. Implementing defined and selective responsiveness to external stimuli is a persisting challenge that critically restricts their functionality. Addressing this challenge, this study introduces a versatile, modular hydrogel system composed of four-arm poly(ethylene glycol)(starPEG)-peptide and glycosaminoglycan(GAG)-maleimide conjugates.
View Article and Find Full Text PDFCureus
December 2024
Internal Medicine, Griffin Hospital, Derby, USA.
Ethylene glycol (C₂H₆O₂), a toxic alcohol commonly found in automotive antifreeze, de-icing solutions, and industrial coolants, can cause severe toxicity when ingested. Due to its sweet taste, it is often consumed accidentally or intentionally, leading to life-threatening consequences such as metabolic acidosis, acute kidney injury (AKI), and mortality. Prompt diagnosis and early treatment with antidotes such as fomepizole or ethanol, combined with hemodialysis, are essential in preventing severe outcomes.
View Article and Find Full Text PDFACS Appl Polym Mater
July 2024
Departament d'Enginyeria Química, Campus Diagonal Besòs (EEBE), Universitat Politècnica de Catalunya Barcelona Tech, Av. Eduard Maristany 10-14, Barcelona 08019, Spain.
Diabetes is a metabolic disorder caused by the body's inability to produce or use insulin. Considering the figures projected by the World Health Organization, research on insulin therapy is crucial. Hence, we present a soft biointerface based on a thiol-yne poly(ethylene glycol) (PEG) click-hydrogel as an advanced treatment option to administrate insulin.
View Article and Find Full Text PDFMater Today Bio
February 2025
Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, W12 0BZ, London, UK.
We present a novel, highly customizable glutathione-responsive nanogel (NG) platform for efficient mRNA delivery with precise mRNA payload release control. Optimization of various cationic monomers, including newly synthesized cationic polyarginine, polyhistidine, and acrylated guanidine monomers, allowed fine-tuning of NG properties for mRNA binding. By incorporating a poly(ethylene) glycol-based disulphide crosslinker, we achieved glutathione-triggered mRNA release, enabling targeted intracellular delivery.
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