Adsorption of cetylpyridinium chloride (CPC), a cationic surfactant, by magnetic alginate beads (MagAlgbeads) was investigated. The magnetic adsorbent (called magsorbent) was prepared by encapsulation of magnetic functionalized nanoparticles in an alginate gel. The influence on CPC adsorption of several parameters such as contact time, pH and initial surfactant concentration was studied. The equilibrium isotherm shows that adsorption occurs through both electrostatic interactions with charge neutralization of the carboxylate groups of the beads and hydrophobic interactions inducing the formation of surfactant aggregates in the beads. The dosage of calcium ions released in the solution turns out to be a useful tool for understanding the adsorption mechanisms. Adsorption is accompanied by a shrinking of the beads that corresponds to a 45% reduction of the volume. Adsorption kinetic experiments show that equilibrium time is strongly dependent on the surfactant concentration, which monitors the nature of the interactions. On the other hand, since the pH affects the ionization state of adsorption sites, adsorption depends on the pH solution, maximum adsorption being obtained in a large pH range (3.2-12) in agreement with the pKa value of alginate (pKa=3.4-4.2). Finally, due to the formation of micelle-like surfactants aggregates in the magnetic alginate beads, they could be used as a new efficient magsorbent for hydrophobic pollutants.
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http://dx.doi.org/10.1016/j.jcis.2014.06.027 | DOI Listing |
ACS Biomater Sci Eng
January 2025
Department of Gastrointestinal Surgery, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong 226001, China.
Perianal fistulas (PAFs) are a severe complication of Crohn's disease that significantly impact patient prognosis and quality of life. While stem-cell-based strategies have been widely applied for PAF treatment, their efficacy remains limited. Our study introduces an injectable, temperature-controlled decellularized adipose tissue-alginate hydrogel loaded with dental pulp mesenchymal stem cells (DPMSCs) for in vivo fistula treatment.
View Article and Find Full Text PDFACS Appl Bio Mater
January 2025
Advanced Magnetic Materials Research Center, School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, North Kargar Street, Tehran 11155-4563, Iran.
Although 3D printing is becoming a dominant technique for scaffold preparation in bone tissue engineering (TE), developing hydrogel-based ink compositions with bioactive and self-healing properties remains a challenge. This research focuses on developing a bone scaffold based on a composite hydrogel, which maintains its self-healing properties after incorporating bioactive glass and is 3D-printable. The plain hydrogel ink was synthesized using natural polymers of 1 wt % N-carboxyethyl chitosan, 2 wt % hyaluronic acid aldehyde, 0.
View Article and Find Full Text PDFSci Rep
January 2025
Catalysts and Organic Synthesis Research Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran.
Int J Biol Macromol
January 2025
Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China; Open Studio for Marine Corrosion and Protection, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266100, China; Key Laboratory of Ocean Observation and Information of Hainan Province, Sanya Oceanographic Institution, Ocean University of China, Sanya 572024, China. Electronic address:
Improving the adsorption capacity of materials for pollutants by means of modification is an important direction in the research of water treatment technology. To improve the applicability of sodium alginate composites in the field of adsorption, magnetic sodium alginate-based hydrogel microsphere adsorbent material FeO@SA/PEI-Fe (FSPF) was synthesized in a single step by using polyethyleneimine grafting modification of sodium alginate by sol-gel method. The material was used for the removal of direct blue GL (DB 200) and direct date red B (DR 13) from simulated wastewater, as well as Cu(II) and Pb(II) from simulated wastewater with heavy metal ions.
View Article and Find Full Text PDFFood Chem
December 2024
College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China. Electronic address:
This research developed a magnetic relaxation switching (MRS) biosensor based on hydrogel sol-gel transition and the CRISPR/Cas12a system (MRS-CRISPR) to detect Salmonella. Herein, the alkaline phosphatase (ALP) labeled with streptavidin was captured by the biotin-modified DNA on magnetic nanoparticles (MNPs) surface, which generated an acidic environment via enzymatic reaction to release Ca and induced the transformation of alginate sol to hydrogels. In contrast, Salmonella activated the trans-cleavage activity of the CRISPR/Cas12a system, interrupting the capture of ALP and the subsequent sol-gel transition.
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