581 results about "N-Hydroxysuccinimide" patented technology

One aspect of the present invention generally relates to methods of sealing a wound or tissue plane or filling a void splace. In a preferred embodiment, the wound is an ophthalmic, pleural or dural wound. In certain instances, the compositions used to seal the wound or tissue plane comprises a polyalkyleneamine. In a preferred embodiment, the polyalkyleneamine is polyethyleneimine. Treatment of the polyethyleneimine with a cross-linking reagent causes the polyethyleneimine polymers to polymerize forming a seal. In certain instances, the cross-linking reagent is a polyethylene glycol having reactive terminal groups. In certain instances, the reactive terminal groups are activated esters, such as N-hydroxy succinimide ester. In certain instances, the reactive terminal groups are isocyanates. In certain instances, the polyethyleneimine has a lysine, cysteine, isocysteine or other nucleophilic group attached to the periphery of the polymer. In certain instances, the polyethyleneimine is mixed with a second polymer, such as a polyethylene glycol containing nucleophilic groups. In certain instances, the compositions used to seal the wound or tissue plane are formed by reacting a polyalkyleneamine bearing electrophilic groups with a cross-linking reagent containing nucleophilic groups. In certain instances, the electrophilic groups on the polyalkyleneamine are activated esters, such as N-hydroxy succinimide ester. In certain instances, the compositions used to seal the wound or tissue plane are formed by reacting a polyalkyleneamine bearing photopolymerizable groups with ultraviolet or visibile light. Compositions used to seal the wound which contain PEI or a derivative of PEI are found to adhere tightly to the tissue. Other aspects of the present invention relate to methods of filling a void of a patient or adhering tissue. In certain instances, the methods use a polyalkyleneamine. In a preferred embodiment, the polyalkyleneamine is polyethyleneimine. Another aspect of the present invention relates to a polymeric composition formed by exposing a polyalkyleneamine to an activated polyalkylene glycol. In certain instances, the composition is attached to mammalian tissue.

A composition comprising a collagen protein and demineralized bone matrix is described wherein the composition is chemically cross-linked with a carbodiimide such as N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride (EDC). The crosslinking reaction can be conducted in the presence of N-hydroxysuccinimide (NHS). The collagen can be in a porous matrix or scaffolding. The DBM can be in the form of particles dispersed in the collagen. A method of making the composition is also described wherein a collagen slurry is cast into the desired shape, freeze dried to form a porous scaffolding and infitrated with a solution comprising the cross-linking agent. The composition can be used as an implant for tissue (e.g., soft tissue or bone) engineering.

A structured drug system that is useful for delivering a drug payload to a specific tissue or cell type is disclosed. The system is based on purified polymalic acid. This polymer isolated from natural sources is biocompatible, biodegradable and of very low toxicity. The polymer is extremely water soluble and contains a large number of free carboxyl groups which can used to attach a number of different active molecules. In the examples disclosed N-hydroxysuccinimide esters of the carboxyl groups are used to attach such molecules. The active molecules include monoclonal antibodies to promote specific cellular uptake and specific pro-drugs such as antisense nucleic acids designed to modify the cellular metabolism of a target cell. The pro-drugs are advantageously linked by a somewhat labile bond so that they will be released under specific conditions. In addition, the system contains amide-linked valine to encourage membrane disruption under lysosomal conditions. Polyethylene glycol groups are attached to extend the drug system's circulation half-life. In addition, fluorescent reported groups can be readily included to aid in visualizing and confirming drug system targeting. The drug system can deliver treatments for a wide range of diseases and is specially advantageous for treatment of neoplasms.

The invention provides a preparation method of bionic coating carrying bioactive factors, which is characterized in that: under a catalyzing system of carbodiimide and N-hydroxy-succinamide, Arg-Gly-Asp (RGD) polypeptide chain containing a disulfide bond is grafted onto polyelectrolyte and then is prepared into RGD grafted polyanion electrolyte solution and RGD grafted bioactive-factor-loaded polycation electrolyte solution, the polyanion electrolyte solution is combined with the polycation electrolyte solution carrying the bioactive factors to establish an organic composite coating carrying the bioactive factors on the surface of planting body through a static self-assembling technology. The composite coating solves the bottleneck problem of bioactive factors used surrounding the planting body, can promote the early growth of osteogenesis surrounding the planting body so as to realize the early osseointegration, and facilitates the long-term stability of the planting body. The method is simple to operate, has moderate preparation conditions, is convenient to control and can realize the continuous production.

The invention relates to a low-toxicity functionalized quantum dot modified by amination beta-cyclodextrin and a preparation method thereof, belonging to the field of a special molecular recognition and diagnosis reagent. The method comprises the following steps that functional-group amino is connected on beta-cyclodextrin by a chemical modification method to obtain amino-group-beta-cyclodextrin;under the action of 1-ethyl-3-(3-dimethyl propylamine) carbodiimide hydrochloride and N-hydroxysuccinimide, amino-group-beta-cyclodextrin is coupled with folic acid to obtain folic acid-beta-cyclodextrin; and by taking silver, zinc and other low-toxicity elements as raw materials, an oil-solubility near-infrared quantum dot is prepared, and folic acid-Beta-cyclodextrin is used to carry out water-solubility modification to the oil-solubility near-infrared quantum dot so as to obtain the low-toxicity functionalized quantum dot modified by amination beta-cyclodextrin. The quantum dot has good water-solubility and low-toxicity; and as emission spectrum is in a near-infrared area, and the folic acid is coupled, the quantum dot can be used for special fluorescence detection of tumors.