5612results about "On/in organic carrier" patented technology

A bicomposite material based on collagen is prepared which has two closely bound layers and is biocompatible, non-toxic, hemostatic and biodegradable in less than a month, and can be used in surgery to achieve hemostasis and prevent post-surgical adhesion. To prepare the material, a solution of collagen or gelatin, which may contain glycerine and a hydrophilic additive such as polyethylene glycol or a polysaccharide, is poured onto an inert support to form a layer 30 .mu.m to less than 100 .mu.m thick. Then a polymeric porous fibrous layer is applied during gelling of the collagen or gelatin, and the resultant material is dried. The polymeric porous fibrous layer may be made of collagen or a polysaccharide, and have a density of not more than 75 mg / cm.sup.2, a pore size from 30 .mu.m to 300 .mu.m and a thickness of 0.2 cm to 1.5 cm.

Matrices for manipulation of biopolymers, including the separation, purification, bilization and archival storage of biopolymers is disclosed.

A functional TFE copolymer fine powder is described, wherein the TFE copolymer is a polymer of TFE and at least one functional comonomer, and wherein the TFE copolymer has functional groups that are pendant to the polymer chain. The functional TFE copolymer fine powder resin is paste extrudable and expandable. Methods for making the functional TFE copolymer are also described. The expanded functional TFE copolymer material may be post-reacted after expansion.

Cell storage and delivery systems and methods for storing and delivering viable cells to a mammal are disclosed. The cell storage and delivery systems include a biodegradable and / or bioabsorbable fibrous matrix physically associated with viable cells to contain and release the cells at a controlled rate. The biodegradable and / or bioabsorbable matrix can be formed by electrospinning fibers of biodegradable and / or bioabsorbable fiberizable material. The methods include methods for storing viable cells and for delivering viable cells to a mammal using the cell storage and delivery system.

A nanofibrillar structure for cell culture and tissue engineering is disclosed. The nanofibrillar structure can be used in a variety of applications including methods for proliferating and / or differentiating cells and manufacturing a tissue. Also disclosed is an improved nanofiber comprising a lipid, lipophilic molecule, or chemically modified surface. The nanofibers can be used in a variety of applications including the formation of nanofibrillar structures for cell culture and tissue engineering.

Reactive surfaces, substrates and methods of producing and using such substrates and surfaces are provided. The substrates and surfaces provide low density reactive groups preferably on an otherwise non-reactive surface for use in different applications including single molecule analyses.

An efficient method for the microfabrication of electronic devices which have been adapted for the analyses of biologically significant analyte species is described. The techniques of the present invention allow for close control over the dimensional features of the various components and layers established on a suitable substrate. Such control extends to those parts of the devices which incorporate the biological components which enable these devices to function as biological sensors. The materials and methods disclosed herein thus provide an effective means for the mass production of uniform wholly microfabricated biosensors. Various embodiments of the devices themselves are described herein which are especially suited for real time analyses of biological samples in a clinical setting. In particular, the present invention describes assays which can be performed using certain ligand / ligand receptor-based biosensor embodiments. The present invention also discloses a novel method for the electrochemical detection of particular analyte species of biological and physiological significance using an substrate / label signal generating pair which produces a change in the concentration of electroactive species selected from the group consisting of dioxygen and hydrogen peroxide.

A composition of enzyme, polymer, and crosslinker forms a network of covalently bound macromolecules. The covalently immobilized enzyme preparation has enzymatic activity, and retains stable activity when dried and stored at ambient conditions. Methods for preparing an immobilized enzyme and methods for using the enzyme are disclosed.

The invention relates to porous polymeric materials, methods of making them, and applications in medical devices. A specific embodiment of the invention encompasses a material comprising a porous polyolefin substrate containing inclusions of a material to which chemical or biological moieties are attached directly or via a spacer.

Devices and methods for the encapsulation of cells on microfluidic platforms are disclosed. The microfluidic device generally includes a plurality of functional regions to shear, focus, and encapsulate a desired cell or group of cells into a droplet. The microfluidic device can further comprise a polymerization zone to form a polymer bead around the droplet.

This invention provides a seamless capsule for synthesizing biopolymer, comprising:(a) an aqueous mixture for synthesizing biopolymer,(b) a seamless capsule layer encapsulating said aqueous mixture, formed from polysaccharide or protein, and,(c) a viscous liquid intermediate layer, present between said aqueous mixture and said seamless capsule layer, which is immiscible with water,wherein said seamless capsule has a diameter of 0.01 to 10.0 mm.This invention can also provide a method for producing the seamless capsule.

Hydrogels containing catalase co-immobilized with an analyte-sensitive enzyme such as glucose oxidase are disclosed. The hydrogels may be pH-sensitive, and preferably are thin and lightly crosslinked. The catalase is present in concentrations ranging generally from 100 units / ml to about 1000 units / ml. These hydrogels have much faster swelling response times as compared to hydrogels without catalase, and are useful in biosensors and analyte-responsive drug delivery devices. The hydrogels also have an increased useful life, due to protection of the immobilize analyte-sensitive enzyme from degradation by hydrogen peroxide.

Active surface coupled polymerases, surfaces that include such polymerases, and methods of making and using surface-attached polymerases are provided.

Endothelial cell attachment to an intravascular stent is promoted by coating the stent with an endothelial cell specific adhesion peptide. Coating is preferably carried out by activating the intravascular stent using plasma glow discharge, applying on the stent a layer or plurality of layers of a polymer such as poly(2-hydroxyethylmethacrylate), applying a tresylation solution containing pyridine and tresyl chloride, and applying a five amino acid peptide having the sequence glycine-arginine-glutamic acid-aspartic acid-valine.

An improved multi-layered diagnostic sanitary test strip for receiving a heterogenous fluid, such as whole blood, to test for presence and / or amount of a suspected analyte in the fluid by facilitating a color change in the strip corresponding to the amount of the analyte in the fluid, wherein the test strip includes fluid volume control dams to prevent spillage of the fluid from the strip and a chemical reagent solution that facilitates end-point testing. The improved test strip comprises no more than two operative layers and: (a) a reaction membrane containing a reagent capable of reacting with the analyte of interest to produce a measurable change in said membrane; (b) an upper support layer defining a sample receiving port for receiving the fluid sample thereat; (c) one or more structures for directing the sample containing the analyte of interest through at least a portion of said reaction membrane; and (d) a lower support layer having a reaction viewing port in vertical alignment with said membrane for displaying said measurable change, said lower support being associated with said upper support to secure said reaction membrane in said test strip.

A tubular tissue scaffold is described which comprises a tube having a wall, wherein the wall includes biopolymer fibrils that are aligned in a helical pattern around the longitudinal axis of the tube where the pitch of the helical pattern changes with the radial position in the tube wall. The scaffold is capable of directing the morphological pattern of attached and growing cells to form a helical pattern around the tube walls. Additionally, an apparatus for producing such a tubular tissue scaffold is disclosed, the apparatus comprising a biopolymer gel dispersion feed pump that is operably connected to a tube-forming device having an exit port, where the tube-forming device is capable of producing a tube from the gel dispersion while providing an angular shear force across the wall of the tube, and a liquid bath located to receive the tubular tissue scaffold from the tube-forming device. A method for producing the tubular tissue scaffolds is also disclosed. Also, artificial tissue comprising living cells attached to a tubular tissue scaffold as described herein is disclosed. Methods for using the artificial tissue are also disclosed.

A process for production of an agglomerate comprises the steps of: passing a flow of one or more gaseous reactants into a reactor; reacting the one or more gaseous reactants within a reaction zone of the reactor to form product particles; agglomerating the product particles into an agglomerate; and applying a force to the agglomerate to displace it continuously away from the reaction zone.

A method of expanding / maintaining undifferentiated hemopoietic stem cells or progenitor cells by obtaining undifferentiated hemopoietic stem cells or progenitor cells; and either seeding the undifferentiated hemopoietic stem cells or progenitor cells into a stationary phase plug-flow bioreactor in which a three-dimensional stromal cell culture has been pre-established on a substrate in the form of a sheet, the substrate including a non-woven fibrous matrix forming a physiologically acceptable three-dimensional network of fibers, thereby expanding / maintaining undifferentiated hemopoietic stem cells or progenitor cells, or culturing the undifferentiated hemopoietic stem cells or progenitor cells in conditioned medium obtained from such a reactor.

The present invention features novel compositions, linkers, derivatized solid supports, and methods for the efficient solid phase synthesis of oligonucleotides, including RNA, DNA, RNA-DNA chimeras, and analogs thereof.

An improved multi-layered diagnostic sanitary test strip for receiving a heterogenous fluid, such as whole blood, to test for presence and / or amount of a suspected analyte in the fluid by facilitating a color change in the strip corresponding to the amount of the analyte in the fluid, wherein the test strip includes fluid volume control dams to prevent spillage of the fluid from the strip and a chemical reagent solution that facilitates end-point testing. The improved test strip comprises no more than two operative layers and: (a) a reaction membrane containing a reagent capable of reacting with the analyte of interest to produce a measurable change in said membrane; (b) an upper support layer defining a sample receiving port for receiving the fluid sample thereat; (c) one or more structures for directing the sample containing the analyte of interest through at least a portion of said reaction membrane; and (d) a lower support layer having a reaction viewing port in vertical alignment with said membrane for displaying said measurable change, said lower support being associated with said upper support to secure said reaction membrane in said test strip.

This disclosure provides an improved system for culturing human pluripotent stem cells. Traditionally, pluripotent stem cells are cultured on a layer of feeder cells (such as mouse embryonic fibroblasts) to prevent them from differentiating. In the system described here, the role of feeder cells is replaced by components added to the culture environment that support rapid proliferation without differentiation. Effective features are a suitable support structure for the cells, and an effective medium that can be added fresh to the culture without being preconditioned by another cell type. Culturing human embryonic stem cells in fresh medium according to this invention causes the cells to expand surprisingly rapidly, while retaining the ability to differentiate into cells representing all three embryonic germ layers. This new culture system allows for bulk proliferation of pPS cells for commercial production of important products for use in drug screening and human therapy.

The present invention refers to new microspheres including pancreatic enzymes, pharmaceutical compositions containing them, and a process to obtain them. The process here described doesn't involve the use of solvents and proves to be remarkably shorter and efficient than the producing methods of the prior arts. The microspheres obtained, including one or more pancreatic enzymes, one or more hydrophilic low-melting polymers and eventual excipients, have an high enzymatic activity, bio-availability and stability.

The present invention relates to injectable compositions comprising biocompatible, hydrophilic, non-toxic and substantially spherical microspheres associated with stem cells useful for tissue construction and generation. The invention also relates to methods of tissue construction and generation, for the treatment of various tissue damage and defects, using the injectable compositions.

The present invention relates to a new method for reversible staining and functional isolation or characterization of cells, e.g. antigen-specific T cells. With this technique, the original functional status of cells can be substantially maintained after their identification and purification. Thus, this new method is of broad benefit for basic research and clinical applications.

The present invention provides a simple and rapid method for preparing purified transposase complexes that are highly suited for fragmenting DNA. The method includes forming transposase complexes with oligonucleotide adapters in cell lysate, then purifying the complexes from the other substance in the cell lysate. Purification is accomplished using a specific binding pair, in which one member of the pair is bound to an oligonucleotide adapter of the complex and the other member of the pair is bound to a solid substrate. The bound complexes can be immediately used in DNA fragmentation reactions to produce solid substrate-bound DNA fragments, which can be used for any number of purposes, including as templates for amplification and sequencing.

The invention relates to viable and stable probiotic formulations for intestinal targeting made of microspheres comprising each a core of one or more probiotic bacteria, microcrystallline cellulose with a degree of polymerization from 165-365 and mean diameter from 45 to 180 μm, a disintegrant and a stabilizer, the core being coated with a non-enteric coating and further coated with an enteric coating. Each probiotic microsphere has a residual moisture level of less than 5% and a water activity (aw) between 0.1 and 0.5. Such a probiotic microsphere shows no reduction in viable bacteria after one hour in simulated gastric fluid. The present invention also relates to the process of preparing such formulation.

Polyhydroxyalkanoates (PHAs) from which pyrogen has been removed are provided for use in numerous biomedical applications. PHAs which have been chemically modified to enhance physical and / or chemical properties, for targeting or to modify biodegradability or clearance by the reticuloendothelial system (RES), are described. Methods for depyrogenating PHA polymers prepared by bacterial fermentation processes are also provided, wherein pyrogens are removed from the polymers without adversely impacting the polymers' inherent chemical structures and physical properties. PHAs with advantageous processing characteristics, including low melting points and / or solubility in non-toxic solvents, are also described. PHAs are provided which are suitable for use in in vivo applications such as in tissue coatings, stents, sutures, tubing, bone and other prostheses, bone or tissue cements, tissue regeneration devices, wound dressings, drug delivery, and for diagnostic and prophylactic uses. Properties which are selected for include degradability, elasticity, inclusion of functional groups or derivatized groups, which can in turn be used to attach targeting agents, and bioadhesion.

Mannitol in certain weight percentages can be used to produce lyophilized beads of consistent size, consistent morphology, and reduced moisture content. These mannitol-containing lyophilized beads are useful in a variety of biological applications where precise reagent amounts are required or moisture-sensitive components are utilized. PCR technologies represent one biological application where mannitol-containing lyophilized beads can be used.

This invention relates to coated digestive enzyme preparations and enzyme delivery systems and pharmaceutical compositions comprising the preparations. This invention further relates to methods of preparation and use of the systems, pharmaceutical compositions and preparations to treat persons having ADD, ADHD, autism, cystic fibrosis and other behavioral and neurological disorders.

A method of manufacturing a nanopatterned biopolymer optical device includes providing a biopolymer, processing the biopolymer to yield a biopolymer matrix solution, providing a substrate with a nanopatterned surface, casting the biopolymer matrix solution on the nanopatterned surface of the substrate, and drying the biopolymer matrix solution to form a solidified biopolymer film on the substrate, where the solidified biopolymer film is formed with a surface having a nanopattern thereon. In another embodiment, the method also includes annealing the solidified biopolymer film. A nanopatterned biopolymer optical device includes a solidified biopolymer film with a surface having a nanopattern is also provided.