Bioscaffold Fabrication by Electrospraying: A Technique to Generate Microcarrier Scaffolds Derived from Extracellular Matrix of Decellularized Tissue

Microcarriers are micron-sized spherical support matrices with interconnected pores that provide an expansive surface for cell attachment and growth.

To fabricate extracellular matrix or ECM-derived microcarriers, begin with a uniform suspension of finely powdered ECM. Load the suspension into a syringe connected to an infusion set. Secure the syringe on a syringe pump. Position the needle vertically over a cryogenic flask at an appropriate distance.

Now, connect the needle to the positive terminal of a high voltage power source. Attach a folded aluminum foil strip over the edge of the flask and connect it to the grounding terminal to complete the circuit.

Next, fill liquid nitrogen in the flask with the inner end of the aluminum strip submerged. Apply the desired voltage and set the syringe pump to a suitable flow rate to initiate electrospraying. As the conductive ECM suspension emerges from the needle tip, its shape deforms under the influence of the electric field and surface tension, forming a pointy liquid cone.

With voltage increments, the suspension jets out. This eventually breaks into charged smaller droplets and falls into the liquid nitrogen bath. Liquid nitrogen instantly freezes the microdroplets, crystallizing the solvent particles within. 

Transfer the frozen microdroplets to a fresh tube. Lyophilize the sample. This step helps remove frozen solvent particles from the sample, generating pores in their place. Store the dry powder of porous microcarriers for further applications.