Only about 5% of drugs administrated by eye drops are bioavailable, and currently eye drops account for more than 90% of all ophthalmic formulations. The bioavailability of ophthalmic drugs can be improved by a soft contact lens-based ophthalmic drug delivery system. Several polymeric hydrogels have been investigated for soft contact ...

Hydrogels are physically or chemically cross-linked polymer networks that are able to absorb large amounts of water. They can be classified into different categories depending on various parameters including the preparation method, the charge, and the mechanical and structural characteristics. The present review aims to give an overview of ...

To accomplish ideal wound healing dressing, a series of waterborne polyurethane (WBPU) hydrogels based on polyethylene glycol (PEG) were synthesized by polyaddition reaction in an emulsion system. The stable WBPU hydrogels which have remaining weight of above 85% were obtained. The effect of the soft segment (PEG) content on water ...

In this paper, a novel protein-based superabsorbent hydrogel was synthesized through crosslinking graft copolymerization of methacrylic acid (MAA) onto collagen, using ammonium persulfate (APS) as a free radical initiator in the presence of methylenebisacrylamide (MBA) as a crosslinker. The hydrogel structure was confirmed using FTIR ...

In this paper, we demonstrate the first hybrid suprastructure of pseudopolyrotaxanes (PPRs) on clay nanoplatelets. Simple end-modification of poly(ethylene glycol) with pyridinium (PEG-N+) enabled the chains to form brush-like conformation on clay surfaces. Thus the PEG chains were able to thread into the cavities of ?-cyclodextrins (?-CDs) leading to hybrid PPR hydrogels. ...

1. Chronic Wound Dressings that Sequester Harmful Proteases: Traditionally the use of carbohydrate-based wound dressings including cotton, xerogels, charcoal cloth, alginates, chitosan and hydrogels, have afforded properties such as absorbency, ease of application and removal, bacterial protection, ...

Chronic Wound Dressings that Sequester Harmful Proteases: Traditionally the use of carbohydrate-based wound dressings including cotton, xerogels, charcoal cloth, alginates, chitosan and hydrogels, have afforded properties such as absorbency, ease of application and removal, bacterial protection, flu...

Traditionally the use of carbohydrate-based wound dressings including cotton, xerogels, charcoal cloth, alginates, chitosan and hydrogels, have afforded properties such as absorbency, ease of application and removal, bacterial protection, fluid balance, occlusion, and elasticity. Recent efforts in ...

A novel superabsorbent hydrogel composite based on Collagen have been prepared via graft copolymerization of Methacrylic acid (MAA) in the presence of kaolin powder using methylenebisacrylamide (MBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator. The composite structure was confirmed using FTIR spectroscopy. A new absorption band at ...

A novel system of body water elimination to be used for the treatment of edemas, based on superabsorbent cellulose derivatives able to absorb large amounts of water and water solutions, has been investigated. Hydrogels have been synthesized starting from water solutions of carboxymethylcellulose sodium salt and hydroxyethylcellulose, ...

We report on liquid-based tunable-focus microlens arrays made of a flexible polydimethylsiloxane (PDMS) polymer. Each microlens in the array is formed through an immiscible liquid-liquid interfacial meniscus. Here deionized water and silicone oil were used. The liquids were constrained in the PDMS structures fabricated through liquid-phase photopolymerization for molding and ...

p(4-vinylpyridine) (p(4-VP)) hydrogels were prepared in bulk (macro, 5�6mm) and in nanosizes (370nm) dimensions. The prepared hydrogels were used to remove organic aromatic contaminates such as 4-nitrophenol (4-NP), 2-nitrophenol (2-NP), phenol (Ph) and nitrobenzene (NB) from an aqueous environment. Important parameters affecting the absorption ...

Hydrogel nanofiber mats based on thermoresponsive multiblock poly(ester urethane)s comprising poly(ethylene glycol) (PEG), poly(propylene glycol) (PPG), and poly(epsilon-caprolactone) (PCL) segments were fabricated by electrospinning. The hydrogel nanofiber mats were more water absorbent under cold conditions and ...

... Temperature sensitive hydrogels based on N-isopropyl acrylamide (NIPA) and acryloyl glucosamine (AG) were synthesized using ammonium ...

... Abstract : Temperature sensitive hydrogels based on N-isopropyl acrylamide (NIPA) and acryloyl glucosamine (AG) were synthesized using ...

... EARLIER. Now several new factors have been discovered that influence the water absorptive capacity of these hydrogel films. ...

Thermoreversible hydrogel scaffolds for articular cartilage engineering John P. Fisher,1 hydrophilic proteogly- cans, an engineered cartilage graft may be based on syn- thetic hydrogels to mimic 35�C, allowing an aqueous solution containing cells at room temperature to form a hydrogel

of these processes are not fully understood, it is believed that the unoxidized catechol form of DOPA is responsible.7 The model catechol of diDOPA has absorbance peaks with max of 268 and 420 nm at pH 3 and 274 weight polymers cross-linked from catechol amines.9 Based on the observed intermediates, melanogenesis

Water absorbency behavior of acrylamide (AAm)/2,3-dihydroxybutanedioic acid (DBA) hydrogels synthesized by ?-radiation crosslinking of AAm and DBA in an aqueous solution was investigated. Different amounts of DBA containing AAm/DBA hydrogels were obtained in the form of rods via a radiation technique. Swelling experiments were ...

Peptide-based hydrogels are an important class of biomaterials finding use in food industry and potential use in tissue engineering, drug delivery and microfluidics. A primary experimental method to explore the physical properties of these hydrogels is rheology. A fundamental understanding of peptide hydrogel ...

Glucose-Responsive Hydrogels Nicholas A. Peppas Christie D. Bures Departments of Chemical.S.A. INTRODUCTION Hydrogels are hydrophilic polymer networks that can absorb large amounts of water, but remain insoluble because of the presence of cross-links, entanglements, or crystalline regions.[1] Hydrogels often

... Accession Number : ADA265528. Title : Amperometric Biosensors Based on 3-Dimensional Hydrogel-Forming Epoxy Networks. ...

Photo- and electropatterning of hydrogel-encapsulated living cell arrays Dirk R. Albrecht,a Valerie)-based hydrogel to create a local 3-D microenvironment. First, `photopatterning' selectively crosslinks hydrogel, represents an important step toward cell-based assays that accurately predict in ...

Cationic HEMA-based hydrogels were synthesized by copolymerizing HEMA with ((methacrylamido)propyl)trimethylammonium chloride (MAPTAC). Swelling equilibria were measured in pure water an in aqueous sodium chloride solutions. Hydrogel swelling is an increa...

Poly(3-acrylamidopropyl)trimethylammonium chloride (p(APTMACl)) hydrogels were synthesized and utilized as absorbents for the removal of toxic arsenate from aqueous medium. The pH-dependent swelling characteristics of the hydrogel were studied, and the experimental parameters that affect the absorption efficiency were investigated. Our ...

Hydrogels are high-water content materials prepared from cross-linked polymers that are able to provide sustained, local delivery of a variety of therapeutic agents. Use of the natural polymer, chitosan, as the scaffold material in hydrogels has been highly pursued thanks to the polymer's biocompatibility, low toxicity, and biodegradability. The advanced ...

The elimination of water from the body represents a fundamental therapeutic goal in those diseases in which oedemas occur. Aim of this work is the design of a material able to absorb large amount of water to be used, by oral administration, in those cases in which resistance to diuretics appears. Sorption and mechanical properties of the cellulose based ...

... Many hydrogel materials are commercially available. Currently our focus is on an alginate based hydrogel because an ...

... dimensional redox epoxy hydrogel on a current collector. In the case of HRP we ... The redox hydrogel was made of a poly(4-vinyl pyridine) backbone ...

A method for analyzing hydrated hydrogel polymer surfaces in ultra-high vacuum atmospheres has been developed. The materials used for this study were commercially available poly(2-hydroxyethylmethacrylate) (HEMA) based hydrogel polymer (soft) contact lens...

Hydrogels and clay slurries are the materials most commonly applied to roots of pines in the southern ... were tested: kaolin clay, two grades of polyacrylamide hydrogels, and a cornstarch-based hydrogel. In ...

... in a non-polymerized form and chemically and photo-polymerized on the lung tissue into an absorbable hydrogel polymer that is intended to seal air leaks over ...

... Abstract : This letter reports on the preparation of alumina fibres based on unidirectional freezing of an alumina hydrogel. ...

... Abstract : This letter reports on the preparation of alumina fibers based on unidirectional freezing of an alumina hydrogel. ...

... Biodegradable hydrogel nanoparticles based on FDA approved biopolymers have been synthesized. The biocompatibility ...