Fabrication of Amyloid-Beta-Releasing Polymer Microbeads for Modeling Alzheimer's Disease

Take a suspension of cells that secrete neurotoxic amyloid-beta mixed with a biocompatible polymer.

Attach the syringe with the suspension to a microbead fabrication device, then push it through as a continuous liquid stream.

A vibration frequency in the device breaks the stream into uniform, micron-sized droplets.

These droplets pass through an electrostatic field and acquire uniform charges to repel each other, preventing merging.

The droplets then fall into a gelation bath containing calcium ions. The ions cross-link the polymer, encapsulating the cells in spherical microbeads.           

Incubate the beads to complete gelation, then collect them on a filter.

Invert the filter over a tube, add a culture medium to wash the beads into the tube, and transfer the suspension to a flask containing the medium.

The polymer matrix allows nutrient access to support cell proliferation while enabling the slow release of amyloid-beta, mimicking the chronic accumulation seen in an  Alzheimer’s diseased brain.

To fabricate the microbeads, in a 20-milliliters syringe, load five milliliters of the cell alginate suspension and attach a syringe to the encapsulator. To start the encapsulator, activ