Image: Matej Kastelic/Shutterstock
Our ability to replicate the intricacies of human organs is progressing rapidly, and now we’re close to creating a cheap heart-on-a-chip.
The pace at which new drugs can be discovered is set to increase dramatically in the years ahead as engineers find ways to accurately replicate the tissue of human organs, in order to test a variety of different formulae quickly and without any potential damage to test subjects.
What has limited the technology so far is the ability to successfully replicate tissue affordably and in large quantities.
Now, however, a team from Harvard University may have solved this problem with a new, affordable ‘heart-on-a-chip’, which can be used to test the reaction of heart tissue to external stimuli.
In a paper published to Biofabrication, the team revealed a platform using a miniaturised structural formation of cardiac muscle on a cantilever of hydrogel.
By using hydrogel, the team is able to accurately replicate the mechanical properties of the extracellular matrix of the heart, with the aim of putting these tissue structures in a microfluidic environment to closely monitor the flow of the drug being tested.
So, to make a chip capable of being manufactured on a large-scale, automated and quality-controlled basis, the Harvard team introduced some photonics.
A composite image showing various aspects of the group’s work. Image: Disease Biophysics Group, Harvard University, Cambridge, MA
60pc faster
“Our new heart-on-a-chip fabrication method uses a UV laser to pattern the hydrogel, employing riboflavin to sensitise the gel for optical ablation,” said the study’s co-lead author, Dr Lisa Scudder.
“This patterning method then allows the cardiac cells to align into organised laminar tissue structures, like in the native heart. The UV micropatterning method creates features on the gel much faster, but with the same resolution and reproducibility as traditional moulding techniques.”
Traditionally, creating a heart-on-a-chip involved manually moulding gelatine to create patterns in the hydrogel for tissue alignment, which takes a long time.
In addition to being scalable, the new process gives great uniformity, doesn’t alter the properties of the hydrogel and is up to 60pc faster than the old process.
Looking to the future, Scudder believes the fabrication method could be expanded to create a brain or skeletal muscle-on-a-chip to mimic disease states such as fibrosis.
Principal investigator Prof Kevin Parker added: “This advance is part of our strategy of building systems so that the pharmaceutical scientist is fighting the drug, not the chip.”
