Low-swelling biocompatible hydrogels

A hydrogel, precursor technology, applied in medical science, prosthesis, etc., can solve problems such as inappropriate spine

Inactive Publication Date: 2010-09-29
CONFLUENT SURGICAL
View PDF27 Cites 24 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, GELFOAM Not suitable for application around the spine and contraindica

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Low-swelling biocompatible hydrogels
  • Low-swelling biocompatible hydrogels
  • Low-swelling biocompatible hydrogels

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0099] Example 1: Low swelling hydrogel formulation

[0100] To prepare the hydrogel, trilysine containing primary amine functional groups was reacted with a branched polyethylene glycol (PEG) electrophilic precursor in a 1:1 electrophile:nucleophile stoichiometric ratio, The multi-branched polyethylene glycol (PEG) electrophilic precursor (sometimes also referred to herein as 4a20k SG) has four branches (4a), each with a total MW of about 20,000 MW of polyethylene glycol And the ends all contain succinimidyl ester electrophilic functional groups (specifically, succinimidyl glutarate, SG).

[0101] Then, instead of using a 6-arm (6a) or 8-arm (8a) precursor containing PEG arms with a total MW of approximately 10,000 (10k) or 20,000 (20k) (with functional groups at the end of each arm) In addition to the tetra-branched precursor, essentially the same hydrogels were prepared, still using the 1:1 ratio of electrophile-nucleophile functional groups.

[0102] Taking 4a20k SG as a...

Embodiment 2

[0112] Example 2: The role of the osmotic environment in swelling

[0113] Hydrogels were prepared by using 4a20k SG as described in Example 1 and exposed to physiologically buffered saline with a pH of 7.0-7.4 and an osmolarity of approximately 300 mOs or to a double strength solution of the same saline to test the effect of osmotic environment on swelling. When n=3 (hydrogel plug per molar concentration of PBS), the degree of swelling from gelation to equilibrium swelling (recorded at 24 hours) averaged 68% for normal saline and 57% for double strength saline. %. These results suggest that differences in osmotic pressure inherent in the swelling environment are not responsible for the decrease in swelling degree of hydrogels prepared with precursors with different branch lengths, as the change in swelling degree is too small to be observed when the branch length increases. explain the generally observed larger variation.

Embodiment 3

[0114] Example 3: Test of low swelling hydrogel in vivo

[0115] Implantation of low-swelling hydrogels in living spines. Formulation 1 was prepared by combining a trilysine precursor with an 8a15k SG (8 branched PEG precursor, each branch having a total PEG MW of approximately 15,000 and at Hydrogel prepared by reacting with succinimide glutarate at the end. The precursor is administered using a dual chamber applicator that mixes and directs the solution to the site of application.

[0116] All 15 dogs underwent total laminectomy at L2 and L5, after which a 1 cm midline dural incision was made and the incision was sutured. Animals were randomly selected as a control group (n=5 animals; no other treatment before suturing), or DUOFLO Dual-chamber pipette (Hemaedics Inc., Malibu, CA) (n=5 animals) or MICROMYST TM A dual chamber applicator (Confluent Surgical Inc., Waltham, MA) (n=5 animals) administered Formulation 1 at both laminectomy sites. Formulation 1 was observed to...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

Some aspects of the present disclosure relate to methods for treating a tissue by forming a low-swelling biodegradable hydrogel in situ adherent to the tissue. In embodiments the hydrogel exhibits negative swelling, i.e., shrinking. Such treatments may be utilized to in cosmetic or reconstructive surgery, in sphincter augmentation, treating nerve inflammation, and the like.

Description

[0001] Cross References to Related Applications [0002] This application is a continuation-in-part of US Patent Application Serial No. 11 / 714,028 filed March 5, 2007, the entire disclosure of which is incorporated herein by reference. technical field [0003] The present invention relates to surgical treatment using hydrogels, in particular to surgical treatment using bioabsorbable, covalently cross-linked hydrogels. Background technique [0004] Hydrogels can be used in vivo for applications such as occlusion, prevention of adhesions, or drug delivery. Hydrogels are often capable of exhibiting a high degree of swelling when combined with water. [0005] However, certain medical applications do not allow high swelling. For example, GELFOAM Absorbable gelatin (Pharmacia & Upjohn, Kalamazoo, MI) is a water-insoluble, porous, soft form of gelatin that is applied to bleeding surfaces as a hemostatic agent. However, GELFOAM Not suitable for application around the spine an...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): A61L27/58A61L27/18A61L27/20A61L27/22A61L27/00A61L27/26
CPCA61L27/18A61L27/58A61L27/52C08L71/02
Inventor 史蒂文·L·贝内特
Owner CONFLUENT SURGICAL
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap