Injectable hydrogels from microfiber suspensions

Patent metadata

Field	Value
Publication number	US-2016346427-A1
Application number	US-201615169010-A
Country	US
Kind code	A1
Filing date	May 31, 2016
Priority date	May 29, 2015
Publication date	Dec 1, 2016
Grant date	—

Abstract

Provided is a hydrogel. The hydrogel includes a liquid and a plurality of microfibers suspended in the liquid as an entangled network. The entangled network includes physically entangled microfibers that are mechanically interlocked.

First claim

What is claimed is:

1 . A hydrogel comprising:
a liquid; and a plurality of microfibers suspended in the liquid as an entangled network, wherein the entangled network comprises physically entangled microfibers that are mechanically interlocked.

2 . The hydrogel of claim 1 , wherein the plurality of microfibers each comprise an aspect ratio of about 200 to about 10,000, wherein a length of the microfibers is greater than a diameter of the microfibers.

3 . The hydrogel of claim 1 , wherein each of the plurality of microfibers comprise lengths in a range of from about 1 mm to about 50 mm.

4 . The hydrogel of claim 1 , wherein each the plurality of microfibers comprise diameters in a range of from about 0.5 μm to about 1500 μm.

5 . The hydrogel of claim 1 , wherein the liquid comprises one or more of a polymer solution, a surfactant, a solute, or combinations thereof.

6 . The hydrogel of claim 1 , wherein each of the plurality of microfibers comprise poly(ethylene glycol) diacrylate (PEG-DA).

7 . The hydrogel of claim 1 , wherein each of the plurality of microfibers comprise a maximum effective stiffness (S eff ) of from about 10 −6 to about 10 −3 as calculated by,

S
eff

=

E
Y


π




D
4

64


η
m



γ
.





L
4

where E Y is Young's modulus, L is fiber length, D is fiber diameter, η m is a viscosity of a flowable suspension prior to shear flow to physically entangle the microfibers, and {dot over (γ)} is a shear rate.

8 . The hydrogel of claim 7 , wherein the plurality of microfibers encapsulate a cargo.

9 . The hydrogel of claim 8 , wherein the cargo comprises one or more of therapeutics, biological materials, or sensing materials.

10 . The hydrogel of claim 1 , wherein the plurality of microfibers are hydrophilic microfibers.

11 . A method of forming a hydrogel, comprising:
providing a flowable suspension comprised of a plurality of microfibers disposed in a liquid carrier, wherein the flowable suspension is a shear thickening fluid; physically entangling the plurality of microfibers by extruding the flowable suspension through an open end of a conduit; and forming the hydrogel by mechanically interlocking the plurality of microfibers.

12 . The method of claim 11 , wherein providing the flowable suspension comprises disposing the flowable suspension in a first chamber having a first cross-sectional area, and wherein extruding comprises flowing the flowable suspension from the first chamber through the conduit, and wherein the conduit comprises a second cross-section area that is smaller than the first cross-sectional area.

13 . The method of claim 12 , wherein the conduit comprises a needle and the first chamber comprises a syringe, wherein the needle comprises a diameter of from about 0.1 mm to about 1 mm, and wherein the syringe comprises a diameter greater than about 10 mm.

14 . The method of claim 11 , wherein the flowable suspension comprises a fiber volume fraction in a range of from about φ=0.2 to about φ=0.4.

15 . The method of claim 11 , wherein the plurality of microfibers comprise high aspect ratio, flexible microfibers formed by a microfluidic method, a wet spinning method, or an electrospinning method.

16 . A biocompatible material comprising:
a shear thickening fluid, the shear thickening fluid comprising,
a liquid, and
a plurality of microfibers suspended in the liquid, wherein the plurality of microfibers encapsulate a therapeutic, and wherein the microfibers have an aspect ratio of about 200 to about 10,000.

17 . The biocompatible material of claim 16 , wherein the shear thickening liquid forms a hydrogel upon in vivo extrusion through a conduit.

18 . The biocompatible material of claim 17 , wherein the hydrogel comprises the plurality of microfibers suspended in the liquid as an entangled network, wherein the entangled network comprises physically entangled microfibers that are mechanically interlocked to each other.

19 . The biocompatible material of claim 17 , wherein the biocompatible material is used as a wound dressing, a scaffolding, or a surgical adhesive.

20 . A hydrogel, comprising:
a liquid; and a plurality of physically entangled fibers disposed in the liquid, wherein the physically entangled fibers are formed by,
providing a flowable suspension comprised of a plurality of fibers disposed in the liquid; and
physically entangling the plurality of fibers by extruding the flowable suspension through an open end of a conduit.

Assignees

• Univ Princeton

Inventors

• Nunes Janine K
• Perazzo Antonio
• Guido Stefano
• Stone Howard A

Classifications

• A61L24/0015

  Medicaments; Biocides · CPC title

• A61L24/001

  Use of materials characterised by their function or physical properties · CPC title

• A61L27/54

  Biologically active materials, e.g. therapeutic substances {(A61L27/227 takes precedence)} · CPC title

• A61L26/0066

  Medicaments; Biocides · CPC title

• A61L26/008

  Hydrogels or hydrocolloids · CPC title