An international team of researchers has used a microfluidic system to produce microsized silk capsules that could be used to deliver delicate proteins or drugs in the body. They extracted silk proteins directly from the glands on silkworms and ran them through small channels on a microfluidic chip to produce the silk capsules. The process is bioinspired by the way that silkworms spin these natural fibers, and the capsules themselves mimic a silkworm cocoon, albeit on a tiny scale.
On the chip, the proteins self-assembled into a gel-like material and formed microscopic silk capsules. By changing the viscosity of the silk solution and the forces affecting it, the researchers could control the size and shape of the silk microcapsules. The natural silk proteins inside the capsules were protected from the outside environment, and in future the capsules could deliver therapeutic protein drugs that are sensitive and normally degrade in the body.
“Making synthetic capsules is normally a complex and energy-intensive process. In contrast, silk capsules are easier to produce and require less energy to manufacture. Moreover, silk is biodegradable,” says Ulyana Shimanovich, a researcher involved in the study, which was recently published in Nature Communications.
One of the most exciting aspects of the capsules is that they can penetrate the blood brain barrier, a specialized layer lining blood vessels in the brain that is normally impenetrable to many drugs and particles. This means that they could be used to deliver drugs to treat neurological diseases.
See the capsules being produced in the following video:
Study in Nature Communications: Silk micrococoons for protein stabilisation and molecular encapsulation…
