Temperature response of double network (DN) hydrogels composed of thermoresponsive poly(-diethylacrylamide) (PDEAAm) and hydrophilic polyacrylamide (PAAm) or poly(-dimethylacrylamide) (PDMAAm) was studied by a combination of swelling measurements, differential scanning calorimetry (DSC) and H NMR and UV-Vis spectroscopies. Presence of the second hydrophilic network in DN hydrogels influenced their thermal sensitivity significantly. DN hydrogels show less intensive changes in deswelling, smaller enthalpy, and entropy changes connected with phase transition and broader temperature interval of the transition than the single network (SN) hydrogels. Above the transition, the DN hydrogels contain significantly more permanently bound water in comparison with SN hydrogels due to interaction of water with the hydrophilic component. Unlike swelling and DSC experiments, a rather abrupt transition was revealed from temperature-dependent NMR spectra. Release study showed that model methylene blue molecules are released from SN and DN hydrogels within different time scale. New thermodynamical model of deswelling behaviour based on the approach of the van't Hoff analysis was developed. The model allows to determine thermodynamic parameters connected with temperature-induced volume transition, such as the standard change of enthalpy and entropy and critical temperatures and characterize the structurally different states of water.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7692105 | PMC |
http://dx.doi.org/10.3390/polym12112502 | DOI Listing |
Soft Matter
January 2025
Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT 06510, USA.
Hydrogels are popular platforms for cell encapsulation in biomedicine and tissue engineering due to their soft, porous structures, high water content, and excellent tunability. Recent studies highlight that the timing of network formation can be just as important as mechanical properties in influencing cell morphologies. Conventionally, time-dependent properties can be achieved through multi-step processes.
View Article and Find Full Text PDFMater Horiz
January 2025
Institute of Biomedical Engineering, College of Medicine, Southwest Jiaotong University, Chengdu 610031, China.
Flexible hydrogel sensors have found extensive applications. However, the insufficient sensing sensitivity and the propensity to freeze at low temperatures restrict their use, particularly in frigid conditions. Herein, a multifunctional eutectogel with high transparency, anti-freezing, anti-swelling, adhesive, and self-healing properties is prepared by a one-step photopolymerization of acrylic acid and lauryl methacrylate in a binary solvent comprising water and deep eutectic solvent (DES).
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Orthopedic Surgery, West China Hospital, Sichuan University, Chengdu 610041, China.
This study explores the use of chicken egg white (EW), a rich source of natural proteins, to address challenges in wound healing management. Herein, a novel Zn-infused EW/GelMA (EW/Gel) hybrid hydrogel is developed, featuring an interpenetrating network (IPN) structure, where the first network consists of photo-cross-linked GelMA and the second network consists of Zn-infused EW (Zn-EW) through ion-protein binding. By optimizing the design and formulation, the resulting Zn-EW/Gel hydrogel exhibited enhanced mechanical stability and self-adhesive properties.
View Article and Find Full Text PDFMater Horiz
January 2025
Key Laboratory of Functional Inorganic Material Chemistry (MOE), School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China.
In such an era of information explosion, improving the level of information security is still a challenging task. Self-erasing luminescent hydrogels are becoming ideal candidates for improving the level of information security with simple encryption and decryption methods. Herein, a lanthanide-polyoxometalate-based self-erasing luminescent hydrogel with time-dependent and resilient properties was constructed through a covalent crosslinked network constructed with polyacrylamide and a non-covalent crosslinked network constructed with [2-(methacryloyloxy)ethyl]trimethyl ammonium chloride/NaDyWO, along with doping urease.
View Article and Find Full Text PDFAnal Chim Acta
February 2025
Key Laboratory of Optic-Electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China. Electronic address:
The accurate and reliable quantification of the levels of disease markers in human sweat is of significance for health monitoring through wearable sensing technology, but the sensors performed in real sweat always suffer from biofouling that cause performance degradation or even malfunction. We herein developed a wearable antifouling electrochemical sensor based on a novel multifunctional hydrogel for the detection of targets in sweat. The integration of polyethylene glycol (PEG) into the sulfobetaine methacrylate (SBMA) hydrogel results in a robust network structure characterized by abundant hydrophilic groups on its surface, significantly enhancing the PEG-SBMA hydrogel's antifouling and mechanical properties.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!