System for conditioning of engineered microtissues
A system and method for conditioning a tissue are provided. The system includes a substrate, a plurality of microwells formed in the substrate, and a microsphere associated with each of the plurality of microwells. The system also includes a pair of flexible pillars within each of the plurality of microwells. Each flexible pillar includes a first end bonded to a respective microwell and at least one flexible pillar has a second end bonded to the microsphere. The flexible pillars are configured to deflect when exposed to a magnetic field to controllably stretch microtissue spanning the flexible pillars.
1. A system for conditioning a tissue comprising:
a substrate;
a plurality of microwells formed in the substrate;
a microsphere associated with each of the plurality of microwells;
a pair of flexible pillars within each of the plurality of microwells, each flexible pillar of the pair of the flexible pillars including a first end bonded to a respective microwell and at least one flexible pillar having a second end bonded to the microsphere; and
wherein the pair of flexible pillars are configured to deflect when exposed to a magnetic field to controllably stretch microtissue spanning the pair of flexible pillars.
2. The system of claim 1 wherein the flexible pillars are configured to bend due to a collective contractile force of the microtissue and wherein a degree of bend of the flexible pillars provides a read-out of a force associated with the microtissue.
3. The system of claim 1 further comprising a magnetic microtissue tester (MMT) configured to assess a contractility of the microtissue during repeated deflection of the flexible pillars to perform a tissue conditioning process.
4. The system of claim 1 further comprising a plurality of silicon-nitride coated wafers bonded to the substrate, each silicon-nitride coated wafer of the plurality of silicon-nitride coated wafers being arranged between the pairs of flexible pillars.
5. The system of claim 4 further comprising a plurality of magnetic bars microfabricated on the silicon-nitride coated wafers.
6. The system of claim 4 further comprising an array of holes extending through the silicon-nitride coated wafers.
7. The system of claim 6 wherein the array of holes include etched holes.
8. The system of claim 4 further comprising gold circuitry disposed on the silicon-nitride coated wafers.
9. The system of claim 8 further comprising nickel islands electro-deposited on the gold circuitry.
10. The system of claim 1 further comprising a plurality of magnetic bars and wherein the deflection of the flexible pillars is due to a magnetic attraction between the microspheres and magnetic bars in the presence of the magnetic field.
11. The system of claim 1 wherein the substrate includes a poly(dimethylsiloxane) PDMS substrate.
12. The system of claim 1 further comprising a magnet configured to apply the magnetic field.
13. The system of claim 12 wherein the magnet is a dual-coil programmable electromagnet.
14. The system of claim 12 wherein the magnet is configured to apply a dynamic magnetic field.
15. The system of claim 12 wherein the magnet is configured to apply a quasi-static magnetic field.
16. The system of claim 1 wherein the microspheres are nickel.
17. The system of claim 1 further comprising:
a plurality of silicon-nitride coated wafers bonded to the substrate, each arranged between the pairs of flexible pillars; and
a plurality of magnetic bars including nickel and microfabricated on the silicon-nitride coated wafers.