Methods of Generating Microparticles and Porous Hydrogels Using Microfluidics

Patent metadata

Field	Value
Publication number	US-2017145169-A1
Application number	US-201615335184-A
Country	US
Kind code	A1
Filing date	Oct 26, 2016
Priority date	Oct 26, 2015
Publication date	May 25, 2017
Grant date	—

Abstract

Provided herein are methods utilizing microfluidics for the oxygen-controlled generation of microparticles and hydrogels having controlled microparticle sizes and size distributions and products from provided methods. The included methods provide the generation of microparticles by polymerizing an aqueous solution dispersed in a non-aqueous continuous phase in an oxygen-controlled environment. The process allows for control of size of the size of the aqueous droplets and, thus, control of the size of the generated microparticles which may be used in biological applications.

First claim

1 . A method of preparing a plurality of microparticles in a microfluidics device in an oxygen-controlled environment comprising the steps of:
(a) providing a continuous phase comprising a non-aqueous liquid and a dispersed phase comprising an aqueous solution comprising a monomer or a macromer, and an initiator; (b) forming a composition comprising microdroplets of said aqueous phase and said non-aqueous liquid; (c) purging said composition comprising said microdroplets and the non-aqueous liquid with an oxygen-free gas; and (d) polymerizing said monomer or said macromer in said microdroplets to form microparticles.

2 . The method of claim 1 , wherein said oxygen-free gas is nitrogen.

3 . The method of claim 1 , wherein said oxygen-free gas is provided at a pressure selected from the range of 0.1 atm to 10 atm.

4 - 5 . (canceled)

6 . The method of claim 5 , where said initiator is a photoinitiator and said step of polymerizing said monomer or macromer is carried out in the presence of ultraviolet light.

7 . The method of claim 6 , wherein said photoinitiator is lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) or Irgacure 1173.

8 . (canceled)

9 . The method of claim 1 , wherein said non-aqueous liquid comprises a fluorocarbon oil.

10 . The method of claim 9 , wherein said fluorocarbon oil is a segregated hydrofluoroether.

11 . (canceled)

12 . The method of claim 1 , wherein said non-aqueous liquid further comprises a surfactant and said surfactant is provided at a concentration selected from the range of 0.1% to 4%.

13 - 14 . (canceled)

15 . The method of claim 12 , wherein said surfactant is a Dolomite FluoroPEG surfactant, RAN Biotechnologies FluoroPEG surfactant or Krytox FSL 157.

16 . The method of claim 1 , wherein said microparticles are hydrogel microparticles.

17 . The method of claim 1 , wherein said microparticles are photodegradable.

18 . The method of claim 1 , wherein said monomer or said macromer is photodegradable.

19 . The method of claim 1 , wherein said aqueous solution comprises a macromer, and said macromer is a polyethylene glycol (PEG)-based macromer.

20 . (canceled)

21 . The method of claim 19 , wherein said polyethylene glycol-based macromer is a PEG-diacrylate (PEGDA) macromer or a PEG-norbornene (PEGNB) macromer.

22 - 23 . (canceled)

24 . The method of claim 1 , wherein said step of purging said composition reduces the amount of oxygen in the composition selected from the range of 1% to 90%

25 . (canceled)

26 . The method of claim 1 , wherein said step of purging said composition reduces the amount of oxygen in the non-aqueous liquid selected from the range of 1% to 90%

27 - 28 . (canceled)

29 . The method of claim 1 , wherein said step of purging said composition further comprises a membrane between said composition and said oxygen-free gas.

30 . (canceled)

31 . The method of claim 29 , wherein said membrane is a polydimethylsiloxane membrane.

32 . The method of claim 1 , further comprising the steps of:
(e) at least partially encapsulating said microparticles within a non-photodegradable polymer, wherein said microparticles are photodegradable; and (f) photodegrading said photodegradable microparticles to produce a composite porous hydrogel.

33 . The method of claim 32 , further comprising the steps of:
(g) contacting said composite porous hydrogel with a biological material, thereby distributing said biological material into pores of said composite porous hydrogel.

34 . (canceled)

35 . The method of claim 33 , wherein said biological material comprises cells.

36 . The method of claim 35 , wherein said pores of said composite porous hydrogel have a lateral dimension to receive an individual cell.

37 . The method of claim 33 wherein said biologically viable material is selected from the group consisting of: mesenchymal stem cells, β cells, satellite muscle cells, proteins, therapeutic small molecules, imaging molecules, secondary nanoparticles and any combination thereof.

38 . The method of claim 1 , wherein said composition is a water in oil emulsion.

39 . (canceled)

40 . A plurality of microparticles prepared by the process of:
(a) providing a continuous phase comprising a non-aqueous liquid and a dispersed phase comprising an aqueous solution comprising a monomer or a macromer, and an initiator; (b) forming a composition comprising microdroplets of said aqueous phase and said non-aqueous liquid; (c) purging said composition comprising said microdroplets and the non-aqueous liquid with an oxygen-free gas; and (d) polymerizing said monomer or said macromer in said microdroplets to form microparticles.

41 . A method for preparing a composite hydrogel with a biological material comprising the steps of:
(a) providing a continuous phase comprising a non-aqueous liquid and a dispersed phase comprising an aqueous solution comprising a photodegradable monomer or a photodegradable macromer, and an initiator; (b) forming a composition comprising microdroplets of said aqueous phase and said non-aqueous liquid; (c) purging said composition comprising said microdroplets and the non-aqueous liquid with an oxygen-free gas; (d) polymerizing said photodegradable monomer or said photodegradable macromer of said microdroplets to form photodegradable microparticles; (e) at least partially encapsulating said photodegradable microparticles within a non-photodegradable polymer; (f) photodegrading said photodegradable microparticles to produce a composite porous hydrogel; and (g) contacting said composite porous hydrogel with a biological material, thereby capturing a portion of said biologically material in said composite porous hydrogel.

42 - 44 . (canceled)

45 . A method for encapsulating a biological material in microparticles comprising the steps of:
(a) providing a continuous phase comprising a non-aqueous liquid and a dispersed phase comprising an aqueous solution comprising a monomer or a macromer, said biological material and an initiator; (b) forming a composition comprising microdroplets of said aqueous phase and said non-aqueous liquid; (c) purging said composition comprising said microdroplets and the non-aqueous liquid with an oxygen-free gas; and (d) polymerizing said monomer or said macromer in said microdroplets to form microparticles containing biological material.

46 . The method of claim 45 , wherein said biological material is a viable biological material.

47 - 48 . (canceled)

49 . The method of claim 45 , wherein said microparticles are photodegradable; further comprising the steps of:
(e) at least partially encapsulating said microparticles within a non-photodegradable polymer, and (f) photodegrading said photodegradable microparticles to produce a composite porous hydrogel having a plurality of pores containing a biological material.

50 . A method for preparing an inverse colloidal crystal containing biological material comprising the steps of:
(a) providing a continuous phase comprising a non-aqueous liquid and a dispersed pha

Assignees

• Univ Wyoming

Inventors

• Oakey John
• KRUTKRAMELIS Kaspars
• Xia Bingzhao

Classifications

• B01J13/0052

  Preparation of gels · CPC title

• B01J2219/00792

  One or more tube-shaped elements · CPC title

• C08F222/102

  of dialcohols, e.g. ethylene glycol di(meth)acrylate or 1,4-butanediol dimethacrylate · CPC title

• C08F216/125

  Monomers containing two or more unsaturated aliphatic radicals, e.g. trimethylolpropane triallyl ether or pentaerythritol triallyl ether · CPC title

• C08F2/48

  by ultraviolet or visible light · CPC title