Injectable composite inks and methods for making and using thereof
Described herein are injectable composite inks composed of a hydrogel continuous phase with a plurality of microgels present within the hydrogel continuous phase. The inks described herein have unique chemical and physical properties that enable them to be printed into a number of different types of articles. The articles produced by the injectable composite inks have numerous medical applications.
1. An injectable composite ink comprising:
a hydrogel continuous phase; and
a plurality of gelatin-containing microgels comprising a hydrogel, the plurality of gelatin-containing microgels comprising the hydrogel being dispersed within the hydrogel continuous phase,
wherein the gelatin-containing microgels comprise gelatin having a bloom strength of between about 200 and about 300,
wherein a concentration of the gelatin in the gelatin-containing microgels is 5% w/v, 10% w/v, or 15% w/v,
wherein hydrogel continuous phase is between about 1 wt % to about 10 wt % of the injectable composite ink,
wherein the gelatin-containing microgels is between about 90 wt % to about 99 wt % of the injectable composite ink, and
wherein the injectable composite ink has a measurable Young's modulus of between 14.4 kPa and 56.8 kPa.
2. The injectable composite ink of claim 1 , wherein the hydrogel continuous phase comprises a different hydrogel than the hydrogel of the gelatin-containing microgels.
3. The injectable composite ink of claim 2 , wherein the hydrogel continuous phase comprises a hydrogel dispersed within the hydrogel continuous phase, wherein the hydrogel comprises one or more of: chitosan, collagen, alginate, hyaluronic acid (HA), heparin, chondroitin sulfate, poly (ethylene glycol) (PEG), or poly (vinyl alcohol) (PVA).
4. The injectable composite ink of claim 1 , wherein the hydrogel continuous phase comprises gelatin.
5. The injectable composite ink of claim 4 , wherein the gelatin has an average molecular weight of between about 50,000 Da to about 100,000 Da.
6. The injectable composite ink of claim 1 , wherein the plurality of gelatin-containing microgels have an average particle size of between about 100 μm and about 500 μm.
7. The injectable composite ink of claim 1 , wherein the gelatin in the plurality of gelatin-containing microgels is cross-linked.
8. The injectable composite ink of claim 1 , wherein the hydrogel continuous phase comprises gelatin in an amount of between about 1 wt % to about 10 wt % of the injectable composite ink.
9. The injectable composite ink of claim 1 , wherein the injectable composite ink further comprises a cross-linking agent.
10. The injectable composite ink of claim 9 , wherein a concentration of the cross-linking agent in the injectable composite ink is between about 0.1% w/v and about 5% w/v transglutaminase.
11. The injectable composite ink of claim 1 , wherein the hydrogel continuous phase and gelatin-containing microgels are covalently cross-linked with one another.
12. The injectable composite ink of claim 1 , wherein the injectable composite ink has an injection force of between 0 N and about 25 N.
13. The injectable composite ink of claim 1 , wherein the injectable composite ink further comprises one or more of: a plurality of cells, a plurality of genes, or a bioactive agent.
14. The injectable composite ink of claim 13 , wherein the plurality of cells comprise fibroblasts.