Corals serve as a host to algae, which in turn produces sugars that the corals consume. Now, though, scientists have created 3D-printed coral that's even more algae-friendly than its natural equivalent – it could help address the problem of coral bleaching, and provide a source of biofuel.
The biocompatible synthetic coral was produced via a collaboration between researchers at Cambridge University and the University of California San Diego. They utilized a light-based rapid bioprinting technique, that can produce objects at micrometer-scale resolution within a matter of minutes.
Each piece of the printed coral incorporates a skeleton that supports what's described as "coral-like tissue." The skeleton is made of a biocompatible polymer gel known as PEGDA, to which cellulose nanocrystals have been added. The tissue, meanwhile, consists of a gelatin-based polymer hydrogel by the name of GelMA, which is combined with living algae cells and more of the cellulose nanocrystals.
Thanks to those crystals, along with cup-like shapes and cylindrical structures in the skeleton, the 3D-printed coral is much better than the real thing at absorbing light and directing it to the algae. In fact, when a commercial strain of microalgae called Marinichlorella kaistiae was incorporated into the material, that algae grew 100 times more densely than it did on natural coral in standard liquid growth mediums.
It is now hoped that once developed further, the technology could be utilized in compact, more efficient bioreactors that grow algae for use in biofuels. Additionally, it may help scientists to develop new techniques for mitigating coral bleaching, by better understanding the relationship between corals and their life-giving algae – in bleaching events, that algae is expelled by the coral.
The research is described in a paper that was recently published in the journal Nature Communications.
And as a side note, this isn't the first 3D-printed coral we've seen. Last year, Israeli scientists created bioplastic coral heads that reef fish appeared to prefer over the genuine article.
Sources: University of Cambridge, University of California San Diego