193 results about "Chemical ligation" patented technology

A class of biological sensing devices that include a substrate comprising an array of carbon nanotubes (CNTs) to which are chemically attached biological molecules is disclosed. The attached biological molecules are capable of electrical conductivity that is responsive to chemical changes occurring as a result of their interaction with target species. A means for means for using DNA as a material of potential in molecular electronic sensor devices, being primarily based on molecular electron-transfer reaction processes between DNA-binding donors and acceptors is also disclosed, including composition, method of manufacture and their use are described.

The present invention relates to novel modified proteins having N-terminal free thiols that can be produced by recombinant methods and are ready for further chemical derivatization. In particular, the invention relates to erythropoietin conjugate compounds having altered biochemical, physiochemical and pharmacokinetic properties. More particularly, one embodiment of the invention relates to erythropoietin conjugate compounds of the formula:

(M)_n-X-A-cys-EPO   (I)

where EPO is an erythropoeitin moiety selected from erythropoietin or an erythropoietin variant having at least one amino acid different from the wild-type human EPO, or any pharmaceutical acceptable derivatives thereof having biological properties of causing bone marrow cells to increase production of red blood cells; cys represents the amino acid cysteine and occurs at position −1 relative to the amino acid sequence of the erythropoietin moiety; A indicates the structure of the residual moiety used to chemically attach X to the thiol group of −1Cys; X is a water soluble polymer such as a polyalkylene glycol or other polymer; M is an organic molecule (including peptides and proteins) that increases the circulating half-life of the construct; and N is an integer from 0 to 15.

The present disclosure provides drug-ligand conjugates that are potent cytotoxins and include a linker between the drug and ligand where the linker has a single amino acid. The disclosure is also directed to compositions containing the drug-ligand conjugates, and to methods of treatment using them.

The invention relates to highly fluorescent metal oxide nanoparticles to which biomolecules and other compounds can be chemically linked to form biocompatible, stable optical imaging agents for in vitro and in vivo applications. The fluorescent metal oxide nanoparticles may also be used for magnetic resonance imaging (MRI), thus providing a multi modality imaging agent.

A method for functionalizing the wall of single-wall or multi-wall carbon nanotubes involves the use of acyl peroxides to generate carbon-centered free radicals. The method allows for the chemical attachment of a variety of functional groups to the wall or end cap of carbon nanotubes through covalent carbon bonds without destroying the wall or endcap structure of the nanotube. Carbon-centered radicals generated from acyl peroxides can have terminal functional groups that provide sites for further reaction with other compounds. Organic groups with terminal carboxylic acid functionality can be converted to an acyl chloride and further reacted with an amine to form an amide or with a diamine to form an amide with terminal amine. The reactive functional groups attached to the nanotubes provide improved solvent dispersibility and provide reaction sites for monomers for incorporation in polymer structures. The nanotubes can also be functionalized by generating free radicals from organic sulfoxides.

A bone implant comprises an active agent on at least a portion thereof. The active agent is locally deliverable to bone proximate the implant in at least a two-phased release scheme. A first phase rapidly releases a first quantity of the active agent, and at least a second phase gradually releases a second quantity of the active agent, whereby bone formation stimulated by the active agent is modulated. In one embodiment, a porous implant comprises a porous portion coated with a calcium phosphate compound and which is contacted with a bisphosphonate compound to form a bisphosphonate layer chemically bound to the calcium phosphate at the surface of the porous portion and to form bisphosphonate molecules being non-chemically attached inside the pores of the porous portion. The non-chemically attached bisphosphonate molecules are released in the subject at a rate greater than that of the chemically bound bisphosphonate layer.

The present invention provides compositions, apparatuses and methods for detecting one or more nucleic acid targets present in a sample. Methods of the invention include utilizing two or more oligonucleotide probes that reversibly bind a target nucleic acid in close proximity to each other and possess complementary reactive ligation moieties. When such probes have bound to the target in the proper orientation, they are able to undergo a spontaneous chemical ligation reaction that yields a ligated oligonucleotide product. In accordance with the invention, the presence of the target(s) of interest can be determined by measuring the presence or amount of ligated oligonucleotide product.

The present invention provides compositions, apparatuses and methods for detecting one or more nucleic acid targets present in a sample. Methods of the invention include utilizing two or more oligonucleotide probes that reversibly bind a target nucleic acid in close proximity to each other and possess complementary reactive ligation moieties. When such probes have bound to the target in the proper orientation, they are able to undergo a spontaneous chemical ligation reaction that yields a ligated oligonucleotide product. In one aspect, the ligation product is of variable length that correlates with a particular target. Following chemical ligation, the probes may be amplified and detected by capillary electrophoresis or microarray analysis.

Provided herein are chemically ligated guide RNA oligonucleotides (lgRNA) which comprise two functional RNA modules (crgRNA and tracrgRNA) joined by non-nucleotide chemical linkers (nNt-linker), their complexes with CRISPR-Cas9, preparation methods of Cas9-lgRNA complexes, and their uses for treatments of viral infections in humans. Also disclosed are processes and methods for preparation of these compounds.

The present invention provides compositions, apparatuses and methods for detecting one or more nucleic acid targets present in a sample. Methods of the invention include utilizing two or more ligation probes that reversibly bind a target nucleic acid in close proximity to each other and possess complementary reactive ligation moieties. When such probes have bound to the target in the proper orientation, they are able to undergo a spontaneous chemical ligation reaction that yields a ligation product that is directly detected or that is amplified to produce amplicons that are then detected. The present invention also provides methods to stabilize sample RNA so that degradation does not significantly affect the results of the analysis.

Methods forming a low-κ dielectric material on a substrate are described. The methods may include the steps of producing a radical precursor by flowing an unexcited precursor into a remote plasma region, and reacting the radical precursor with a gas-phase silicon precursor to deposit a flowable film on the substrate. The gas-phase silicon precursor may include at least one silicon-and-oxygen containing compound and at least one silicon-and-carbon linker. The flowable film may be cured to form the low-κ dielectric material.

Disclosed herein is a method for chemically attaching carboxyl, alcohol, amine or amide groups to the surface of nanodiamond (ND) in a liquid phase. Also disclosed herein are a functional ND compound obtained by the method and use thereof. The method includes treating synthetic ND with a size of 1 nm-1OO nm with sonication and a strong acid to provide ND-(COOH)_n. The ND-(COOH)_n compound is used as a starting material to provide ND compounds having alcohol, amine or amide groups attached to the surfaces thereof. The surface-functionalized ND compounds are characterized by using an X-ray diffractometer, FTIR, AFM, particle size analyzer and zeta sizer. The ND compounds show functionalities as well as high solubility to provide stable ND solutions in a liquid phase. Therefore, the ND compounds may be used as diamond coating agents. The powder of the ND compounds may be used as materials for producing composites of polymers, plastics, synthetic fibers, ceramics, etc., or as additives for toothpaste, shampoos, soap and cosmetic compositions.

Compositions, systems, and methods for ink-jet printing having improved black to color bleed control, reduced wicking, and/or reduced halo are described. The composition can include a functionalized carbon pigment dispersed in an ink vehicle. The carbon pigment includes functional groups chemically attached thereto. Suitable functional groups includes an aromatic ring structure having multiple carboxyl groups (or salts thereof) attached to the aromatic ring structure, wherein at least two of the multiple carboxyl groups are positioned on adjacent carbon atoms of the aromatic ring structure.

Heparin-binding regions of several proteins, such as neural cell adhesion molecule, fibronectin, laminin, midkine, and anti-thrombin III have been shown to promote neurite extension on two-dimensional surfaces. The effect of heparin-binding peptides on neurite extension through three-dimensional matrices was investigated by culturing embryonic chick dorsal root ganglia (DRG) within fibrin gels containing chemically attached heparin-binding peptide (HBP). The length of neurites within fibrin gels containing cross-linked HBP was increased by more than 70% over extension through fibrin gels containing no peptide. The HBP sequence of antithrombin III was incorporated into the fibrin gel as the C-terminal domain of a bidomian, chimeric peptide; the N-terminal second domain of this peptide contained the ∀2-plasmin inhibitor substrate for Factor XIIIa. Factor XIIIa, a transglutaminase, was used to chemically attach the HBP-containing chimeric peptide to the fibrin gels during polymerization. The amount of HBP cross-linked into the fibrin gels was determined, after degradation by plasmin using gel permeation chromatography, to be approximately 8 moles of peptide per mole fibrinogen. A peptide (HBP), where the cross-linking glutamine was replaced with glycine, showed no increase in extension in comparison with fibrin gels. The additional of heparin to the gel percursors resulted in no increase in neurite extension in comparison with fibrin gels. HBPs promote neurite extension by binding to cell surface proteoglycans on the DRG.

Novel compounds having a fluorescence quencher as a leaving group are disclosed. Nucleic acids and other molecules containing a fluorophore and a fluorescence quencher are disclosed as an embodiment of this invention. The use of the oligonucleotides in enzyme-free oligonucleotide ligation reactions results in an increase in fluorescence when the oligonucleotide also contains a nearby fluorophore. The ligation reactions can be performed in solution, on surfaces, or in cells.

The invention provides an ocular socket prosthesis comprising a hydrogel consisting essentially of a biocompatible hydrophilic polymer onto which tissues can be directly sutured. Preferably the prosthesis comprises the polymer both in its homogeneous gel form and in its sponge form, and the two forms are chemically joined at their interface via an interpenetrating polymer network (IPN). However, it is also contemplated that the prosthesis of the invention may be made predominantly or entirely from the sponge form of the polymer. Methods of production of the prosthesis of the invention and of surgical implantation are also disclosed and claimed.

The invention designs and synthesizes a series of paclitaxel-oleic acid small-molecular prodrugs; with the application of a chemical connecting arm which is sensitive to an oxidation-deoxidation environment, the rapid release of the drugs in tumor cells is promoted. On the basis, small-molecular prodrug self-assembled nano-drug delivery systems are prepared. The small-molecular prodrug self-assembled nano-drug delivery systems have the advantages that by virtue of a one-step nano-precipitation method, nano-drug self-assembled nanoparticles are simple in preparation process and easy for industrialization; the nano-drug self-assembled nanoparticles are small and uniform in grain size (to 100nm), and the nano-drug self-assembled nanoparticles are enriched in a tumor part by virtue of an EPR (enhanced permeability and retention) effect; an ultrahigh drug-loading capacity is guaranteed, which is beneficial for reducing adverse reactions caused by auxiliary materials and biological materials; surface modification is easy to implement, and the intake of a reticuloendothelial system can be effectively avoided and the intake of the tumor cells to the nanoparticles can be improved by virtue of PEG (polyethylene glycol) and active targeting modification; and on the basis of the sensitivity of the chemical connecting arm to the oxidation-deoxidation microenvironment of the tumor cells, the specific drug release of paclitaxel in the tumor part is achieved, a curative effect is improved and toxic and side effects are reduced.

A reactive nanometer inorganic particle/epoxy resin abrasive composite material and its production are disclosed. The composite material consists of epoxy resin 90-99wt%, nanometer inorganic particle 1-10wt% and graft monomer 0.1-5%. The graft monomer is mixture of any kind or several kinds of methyl acrylic acid ethylene oxide ester, acrylic amide, phenylethylene, ethyl acrylate, methyl ethyl acrylate or butyl acrylate. The process is carried out by surface graft modifying nanometer grains, inducing reactive polymer, epoxy resin curing reacting and forming chemical connection between nanometer grains and resin matrix. It has better anti-friction and wear-resistant performances and is simple. It can be used for epoxy resin coating and various miniature devices.

The present invention relates to surface modifying agents for polymeric and/or textile materials, methods of making and/or using a surface modifying agent to modify and functionalize polymeric and/or textile materials, and/or methods of using surface modified or functionalized polymeric and textile materials, and/or products using or incorporating surface modified or functionalized polymeric and textile materials. For example, the surface modifying agent in precursor form can be styrene sulfonyl azide monomer, polymer or copolymer capable of undergoing a chemical reaction in the presence of heat or light to form one or more styrene sulfonated nitrene monomers, polymers or copolymers, which are capable of chemically reacting with the surface of a polymeric or textile material to endow a specific or desired chemical surface functionality to the surface of a polymeric or textile material. Furthermore, the present invention is possibly preferably directed to a surface modifying agent which comprises a styrene sulfonated nitrene monomer, polymer or polymer containing one or more nitrene functional groups, which are capable of chemically reacting via an insertion reaction into one or more carbon-hydrogen bonds on the surface of a polymeric or textile material in order to chemically attach a specific or desired chemical functionality to the surface of a polymeric or textile material.