Gelatin-based hydrogel functionalized with taurinemoieties for in vivo skin tissue regeneration

Functionalized hydrogels stimulate the migration and morphogenesis of endothelial cells(ECs)and are useful substrates for wound healing.The present study investigates the feasibility of covalent conjugation of taurine(Tau)on a gelatin-based hydrogel.This hydrogel is expected to maintain positive charged growth factors such as basic fibroblast growth factor(bFGF)and vascular endothelial growth factors(VEGFs)near ECs within the hydrogel microenvironment.The gelatin was conjugated with hydroxyl phenol(Ph)and Tau moieties,and in following that Ph residues were crosslinked through a horseradish peroxidase-catalyzed reaction.The migration characteristics of ECs were analyzed by scratch migration assay and microparticle-based cell migration assay.Cellular morphology and amounts of angiopoietin 1(Ang 1),bFGF,and VEGF proteins were evaluated for encapsulated cells.The potential of synthesized hydrogels in wound healing was assessed by the percentage of reduction from the original wound size and histopathological analyses of rat skin.The incorporated Tau molecules within the hydrogel remained stable through covalent bonds during incubation.During extended incubation,the gelatin-based hydrogel conjugated with Tau improved the migration distance and number of existing migrated ECs.Immobilized Tau within the gelatin-based hydrogel induced high motility of ECs,accompanied by robust cytoskeleton extension and a cell subpopulation that expressed CD44 and CD31 receptors as well as enhancement of Ang 1,bFGF,and VEGF.We found that injectable Gel-Ph-Tau effectively improves wound-healing parameters.

Chitosan-based Nanosystems as Drug Carriers

The formation and application of polymeric nanomaterials is great demand in science,industry,biotechnology,and medicine due to the possibility of achieving a significant improvement in the physicochemical,mechanical,and barrier properties of polymers and using them as drug carriers and fillers,which is especially promising for biodegradable polymers such as chitosan and their derivatives.The article presents methods for creating polymer nanostructures based on polysaccharides and,in particular,chitosan.Obtaining nanostructured samples of chitosan using the approaches of chemical transformation and modification of polysaccharides is an urgent scientific problem,the solution of which makes it possible to obtain new polymer systems of great practical interest.The medical aspects of the use of polymer carriers based on chitosan for the treatment of various diseases are discussed.The unique specificity of the properties of chitosan and nanomaterials derived from it,with the properties inherent in this natural polymer,can serve as a promising future,especially in the field of medicine.

The effect of altering crosslinker chemistry during interfacial polymerization on the performance of nanofiltration membranes for desalination, organic, and micropollutants removal

Chemistry of the polyamide active layer of a desalination membrane is critical in determining both its physical and chemical properties.In this study,we designed and fabricated three novel membranes with different active layers using the crosslinkers:terephthaloyl chloride,isophthaloyl chloride,and trimesoyl chloride.The crosslinkers were reacted with an aqueous solution of an aliphatic tetra-amine.Because these crosslinkers differ in their structures and crosslinking mechanisms during interfacial polymerization,the resultant membranes also possess different structural properties.The water contact angle of the fabricated membranes also varies;the water contact angles of 4A-3P-TPC@PSF/PET,4A-3P-TMC@PSF/PET,and 4A-3P-IPC@PSF/PET,are 68.9°,65.6°,and 53.9°,respectively.Similarly,the desalination performance of resultant membranes also showed variations,with 4A-3P-TPC@PSF/PET,4A-3P-IPC@PSF/PET,and 4A-3P-TMC@PSF/PET having a permeate flux of 17.14,25.70,and 30.90 L·m^(−2)·h^(−1),respectively,at 2.5 MPa.The 4A-3P-TPC@PSF/PET membrane exhibited extensive crosslinking with aliphatic linear amine,and cationic dye rhodamine B,MgCl_(2),and amitriptyline rejection rates of 98.6%,92.7%and 80.9%,respectively.The 4A-3P-TMC@PSF/PET membrane showed mediocre performance,while 4A-3P-IPC@PSF/PET membrane showed even lower performance,with a 35%rejection of methyl orange dye.

Achieving High CO_(2)Photoreduction Activity by Conductive Crosslinks of Metal–Organic Framework

Fast photogenerated charge migration is crucial for the improvement of photocatalytic performance,but its deliberate modulation is difficult.This work presents two Zr-based metal–organic framework catalysts,GDUT-8 and GDUT-8-Ox,for photocatalytic CO_(2)reduction.Specifically,thiophene pendants in GDUT-8 were coupled covalently via Scholl reaction to give GDUT-8-Ox,a catalyst with at least two orders of magnitude(up to 6.1×10^(−3)S cm^(−1))enhanced conductivity and faster transport of photogenerated carriers during photocatalysis.Furthermore,from GDUT-8 to GDUT-8-Ox,stronger ligand-to-cluster charge transfer with pronounced light absorption extension was observed.As a result,GDUT-8-Ox exhibited the highest photocatalytic CO_(2)-to-HCOO−conversion rate(1725μmol g^(−1)h^(−1))to date,in the absence of photosensitizer,as well as turnover number,turnover frequency,and quantum efficiency much higher than GDUT-8.This work presents an unprecedented strategy to accelerate the photogenerated carrier transport of photocatalysts.