2257 results about "Polyelectrolyte" patented technology

A new class of poly(beta-amino alcohols) (PBAAs) has been prepared using combinatorial polymerization. The inventive PBAAs may be used in biotechnology and biomedical applications as coatings (such as coatings of films or multilayer films for medical devices or implants), additives, materials, excipients, non-biofouling agents, micropatterning agents, and cellular encapsulation agents. When used as surface coatings, these PBAAs elicited different levels of inflammation, both in vitro and in vivo, depending on their chemical structures. The large chemical diversity of this class of materials allowed us to identify polymer coatings that inhibit macrophage activation in vitro. Furthermore, these coatings reduce the recruitment of inflammatory cells, and reduce fibrosis, following the subcutaneous implantation of carboxylated polystyrene microparticles. These polymers may be used to form polyelectrolyte complex capsules for cell encapsulation. The invention may also have many other biological applications such as antimicrobial coatings, DNA or siRNA delivery, and stem cell tissue engineering.

The present invention comprises an automated apparatus capable of spray depositing polyelectrolytes via the LbL mechanism with minimal or no human interaction. In certain embodiments, the apparatus sprays atomized polyelectrolytes onto a vertically oriented substrate. To counteract the effects of irregular spray patterns, the substrate is preferably slowly rotated about a central axis. In certain embodiments, the apparatus also includes a forced pathway for the droplets, such as a pathway created by using a vacuum. In this way, a thicker or three-dimensional substrate can be coated. In certain embodiments, the apparatus is designed so as to be scalable. Thus, through the use of multiple instantiations of the apparatus, a large or irregularly shaped substrate can be coated. Rolls of textile can therefore be coated using the apparatus. Additionally, the present invention includes a method to uniformly coat a substrate, such as a hydrophobic textile material, using aqueous solutions of polyelectrolytes.

The invention relates to methods for preparing crosslinked polyelectrolytes, in particular crosslinked polyelectrolytes multilayer films. The invention also relates to a method of coating a surface, and the obtained coated article.

A method for making an article comprising a core material and a coating thereon, the method comprising the steps of:(a) providing the core material;(b) applying one or more layers of a crosslinkable polycationic material, wherein the polycationic material is a reaction product of:(i) an epoxide of formula (I)wherein X equals bromo, chloro, iodo, or cyano, and R1, R2, R3, R4, independently of one another, are selected from the group consisting of hydrogen, linear or branched C1-C6-alkyl, and linear or branched C1-C6-alkyl which is substituted with halogen, and(ii) a polymer having repeating units comprising one or more secondary or tertiary amine group(s);(c) applying one or more layers of a polyanionic material; and(d) cross-linking the layers of polyelectrolytes formed by steps (b) and (c).The articles obtainable by the method of the invention have desirable characteristics regarding adherence to the core material, durability, hydrophilicity, and wettability and are thus useful for the manufacture of medical articles such as ophthalmic devices.

Described herein are medical devices which are configured for implantation or insertion into a subject, preferably a mammalian subject. The medical devices contain one or more multilayer regions, which contain: (a) one or more (typically a plurality of) charged nanoparticle layers and (b) one or more (typically a plurality of) charged polyelectroyte layers. Such multilayers have a number of desirable attributes, including high strength, non-compliance, and flexibility. Also described herein are methods of making such devices.

Monodisperse colloidal nanocrystal clusters of magnetite (Fe3O4) with tunable sizes from about thirty to about three hundred nanometers have been synthesized using a high-temperature hydrolysis process. The colloidal nanocrystal clusters are capped with polyelectrolytes, and highly water soluble. Each cluster is composed of many single magnetite crystallites, thus retaining the superparamagnetic behavior at room temperature. The combination of superparamagnetic property, high magnetization, and high water dispersibility makes the colloidal nanocrystal clusters ideal candidates for various important biomedical applications such as drug delivery and bioseparation. The present invention is further directed to methods for forming colloidal photonic crystals from both aqueous and nonaqueous solutions of the superparamagnetic colloidal nanocrystal clusters with an external magnetic field applied thereto. The diffraction of the photonic crystals can be tuned from near infrared to visible and further ultraviolet spectral region by varying the external magnetic field.

A process for preparing nanoparticle coated surfaces including the steps of electrostatically coating surfaces with polyelectrolyte by exposing the surface to a solution or suspension of polyelectrolyte, removing excess non-bound polyelectrolyte, then further coating the particles with a multi-layer of charged nanoparticles by exposing the polyelectrolyte-coated surface to a fluid dispersion including the charged nanoparticles. The process steps can optionally be repeated thereby adding further layers of polyelectrolyte followed by nanoparticles as many times as desired to produce a second and subsequent layers. The polyelectrolyte has an opposite surface charge to the charged nanoparticles and a molecular weight at the ionic strength of the fluid that is effective so that the first, second, and subsequent layers independently comprise a multiplicity of nanoparticle layers that are thicker than monolayers.

The present invention is directed toward water-soluble supramolecular self-assemblies and a process for their preparation via micellization of polyelectrolytes through the use of hydrophobic monomeric units. In this invention the polyelectrolyte segment ultimately forms the core of the supramolecular assembly whereas the shell consists of uncharged hydrophilic polymers or oligomers. It has been determined that the inclusion of the hydrophobic co-monomers to the polyelectrolyte segment forming the micelle core leads to a structure of enhanced stability.

A decomposable thin film comprising a plurality of polyelectrolyte layers of alternating charge, wherein decomposition of the thin film is characterized by degradation of at least a portion of the polyelectrolyte layers.

The invention relates to a method for preparing a biomedical material of a static self-assembly modified nano fiber, which is characterized by comprising the following concrete steps of: stirring and dissolving a water-insoluble macromolecular polymer for spinning in a solvent in a stirring kettle at room temperature to obtain an electric spinning raw material with the weight percentage of 5-30 percent; adding the electric spinning raw material into a static spinning device and statically spinning to obtain a nano fiber template material; soaking the nano fiber template material into a weak polymerized electrolyte aqueous solution which has the concentration of 0.01-10g / ml and an opposite charge, adsorbing for balance and drying; soaking the dried material into the weak polymerized electrolyte aqueous solution which has the concentration of 0.01-10g / ml and the opposite charge, adsorbing for balance, washing by distilled water for 5-30 minutes and drying; and obtaining the biomedical material of the static self-assembly modified nano fiber. The invention has simple molding and high bioactivity.