2 edition of Hydrogels containing linear and cyclic polyethers. found in the catalog.
Hydrogels containing linear and cyclic polyethers.
Helen Rachel Oxley
by Aston University. Department of Chemical Engineering and Applied Chemistry in Birmingham
Written in English
Thesis (PhD) - Aston University, 1991.
This study examines the feasibility of incorporating the antimicrobial peptide subtilosin within covalently cross-linked polyethylene glycol (PEG)-based hydrogels for vaginal administration. The PEG-based hydrogels (4% and 6% [wt/vol]) provided a two-phase release of subtilosin, with an initial rapid release rate of μg/h (0 to 12 h. Hydrogels can adhere to various materials as plastics due to hydrophobic interactions and it can be used as sealant for vessels containing corrosive acids. Contact lenses. It is the most widely used application of this polymer. For soft contact lenses, poly(2-hydroxyethyl methacrylate)-based hydrogels are used due to their extensive property .
Handbook of Hydrogels: Properties, Preparation & Applications (Chemical Engineering Methods and Technology Series) UK ed. Edition by David B. Stein (Author, Editor) ISBN ISBN Why is ISBN important? ISBN. This bar-code number lets you verify that you're getting exactly the right version or edition of a book. Hydrogels: Methods of Preparation, Characterisation and Application al., ). The weight (W 1) of a 70 mm glass fibre paper (pore size micron) is determined following drying in an oven at o C for 1 hour and subsequently cooled in a desiccator containing silica gel.
containing hydrogels exhibit pH-independent swelling. Increase of the AMPS Na content from 0 to 80 mol % results in a fold increase in the hydrogel volume in water. In M NaCl solution, the swelling ratio is almost independent on the ionic linear deformation ratio. a is related to the normalized gel volume V r by the equation a ¼. ‘Clickable’ hydrogels for all: facile fabrication and functionalization†. Luca Beria ab, Tugce Nihal Gevrek b, Asli Erdog b, Rana Sanyal b, Dario Pasini * a and Amitav Sanyal * b a Department of Chemistry and INSTM Research Unit, University of Pavia, , Pavia, Italy. E-mail: @; Fax: +; Tel: + b Department of Chemistry, Bogazici.
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Hydrogels made from natural polymers such as cellulose, sodium alginate, chitosan, dextran, gelatin, hyaluronic acid, and albumin possess inherent biocompatibility, biodegradability, and support cellular activities.
Natural polymer-based hydrogels can be prepared using physical, chemical, or. Hydrogels are a unique class of polymer which swell, but do not dissolve in, water. A range of 2-hydroxyethyl methacrylate based copolymer hydrogels containing both cyclic and linear polyethers have been synthesised and are described in this thesis.
Initially, cyclic polyethers were occluded within the polymer matrix and the transport Author: H.R. Oxley. Hydrogels Based on Natural Polymers presents the latest research on natural polymer-based hydrogels, covering fundamentals, preparation methods, synthetic pathways, advanced properties, major application areas, and novel characterization techniques.
The advantages and disadvantages of each natural polymer-based hydrogel are also discussed, enabling preparation tactics for specific. Hydrogel selection guide.
The first generation of hydrogels used for 3D cell culture was use of ECM components; it was rapidly followed by more sophisticated systems, generated by doing an extraction of ECM polymers from Engelbreth-Holm-Swarm (EHS) murine sarcoma cell basal membranes (ECM based hydrogels).New generations of synthetic, hybrid or peptides-based materials have been developed.
Hydrogels have existed for more than half a century, and today they have many applications in various processes ranging from industrial to biological. There are numerous original papers, reviews, and monographs focused on the synthesis, properties, and applications of hydrogels.
This chapter covers the fundamental aspects and several applications of hydrogels based on the old Cited by: The strained three-membered ring of an epoxide group can be opened by a variety of nucleophiles [1,2].For example, carboxylic acid, phenol, alcohol, and thiol-based nucleophiles can give efficient access to polyesters, polyethers, and polythioethers when treated with appropriately designed epoxy monomers in the presence of a base catalyst [3,4,5,6,7,8,9,10,11,12,13,14,15].
Kaufmann D, Fiedler A, Junger A, Auernheimer J, Kessler H, Weberskirch R. Chemical conjugation of linear and cyclic RGD moieties to a recombinant elastin-mimetic polypeptide – a versatile approach towards bioactive protein hydrogels. Macromol Biosci. ; 8 (6)– [Google Scholar].
The review summarizes current trends and developments in the polymerization of alkylene oxides in the last two decades sincewith a particular focus on the most important epoxide monomers ethylene oxide (EO), propylene oxide (PO), and butylene oxide (BO).
Classical synthetic pathways, i.e., anionic polymerization, coordination polymerization, and cationic polymerization of epoxides. Hydrogels may be categorized into four groups on the basis of presence or absence of electrical charge located on the cross-linked chains: (a) Nonionic (neutral).
(b) Ionic (including anionic or cationic). (c) Amphoteric electrolyte (ampholytic) containing both acidic and basic groups. (d) Zwitterionic (polybetaines) containing both anionic and. Hydrogels may be categorized into four groups on the basis of presence or absence of electrical charge located on the cross-linked chains: (a) Nonionic (neutral).
(b) Ionic (including anionic or cationic). (c) Amphoteric electrolyte (ampholytic) containing both acidic and basic groups. Hydrogels can also be stimuli sensitive and respond to surrounding environment like temperature, pH and presence of electrolyte (Nho et al., ).
These are similar to conventional hydrogels except these gels may exhibit significant volume changes in response to small changes in pH, temperature, electric field, and light. Hydrogels are commonly used in clinical practice and experimental medicine for a wide range of applications, including drug delivery, tissue engineering and regenerative medicine, diagnostics, cellular immobilization, separation of biomolecules or cells, and barrier materials to regulate biological adhesions.
then the hydrogels are termed as permanent hydrogel. The examples of perma-nent hydrogels include pMMA and pHEMA. If the hydrogels are formed due to the physical interactions, viz., molecular entanglement, ionic interaction and hy-drogen bonding, among the polymeric chains then the hydrogels.
Hydrogels containing hydrophobic domains or nanodomains, especially of the micellar type, are reviewed. Examples of the reasons for introducing hydrophobic domains into hydrophilic gels are given; typology of these materials is introduced.
Synthesis routes are exemplified and properties of a variety of such hydrogels in relation with their intended applications are described. Cross linking of linear polymers by irradiation or by chemical compounds. Monomers used here contain an ionizable group that can be ionized or can undergo a substitution reaction after the polymerization is completed.
Thus, the hydrogels synthesized may contain. structure is made by crosslinking hydrophilic polymer chains. An example is chitosan (a linear polysaccharide polymer) crosslinked with glutaraldehyde.
Two applications are scaffolding for soft tissue engineering and adhesive for peripheral nerve repair. Another way to classify hydrogels is on the basis of polymer origin, either natural or.
Hydrogels. An early example of a physically crosslinked gel that targeted a known application was the preparation of a phase seperable graft copolymer that functioned as a hydrogel.(9) Well defined polystyrene macromonomers were prepared by ATRP using vinyl chloroacetate as an initiator.
This book is concerned with polymeric hydrogels, which are considered as one of the most promising types of new polymer-based materials. Each chapter in this book describes a selected class of polymeric hydrogels, such as superabsorbent hybrid nanohydrogels, conducting polymer hydrogels, polysaccharide-based or protein-based hydrogels, or gels based on synthetic polymers.
Cyclic Polyethers acting as mobile carriers in facilitated transport can cause changes of as much as three orders of magnitude in the fluxes of various cations across liquid membranes. Polymer hydrogels are rapidly developing group of materials, providing wide application in many fields, especially pharmacy, medicine and agriculture.
Many reports have been published about new chemical and physical structures, properties and innovative restricted applications of polymer hydrogels.
A series of cyclic aromatic disulfide oligomers have been synthesized in high yields by catalytic oxidization of arenedithiols in DMAc. The aryl groups contain moieties such as ketone, sulfone, isopropylidene, ether, thioether, and phenylphosphine oxide groups.
The cyclic aromatic disulfide oligomers have been analyzed by gradient HPLC, GPC, 1H-NMR, MALDI-TOF-MS, DSC, and TGA .Conducting polymer hydrogels reviewed in this article are gels containing a conducting polymer along with a supporting polymer as components, and they are swollen with water or electrolyte solution.
Polyaniline, polypyrrole, and exceptionally poly(3,4-ethylenedioxythiophene) (PEDOT) are currently used conducting moiety, while cross-linked water.Cyclodextrins (CD) are a group of cyclic oligosaccharides with a cavity/specific structure that enables to form inclusion complexes (IC) with a variety of molecules through non-covalent host-guest interactions.
By an elegant combination of CD with biocompatible, synthetic and natural polymers, different types of universal drug delivery systems with dynamic/reversible properties have been.