Pollen are small grains produced by trees, grasses and herbs. They are essential for the sexual reproduction in plants. Pollination is immensely important for us humans. Without it, our plants wouldn’t make the produce that we eat. They are also highly useful in forensic, archaeological, paleontological and paleoecological scientific studies.
Pollens are normally of a size of 15 to 200 μm diameter. Some of them can cause allergic reactions, adversely influencing health and well-being in individual human beings. This is a widespread phenomenon, affecting large numbers of humans globally. And this is why, if you hear about pollen, your brain automatically gives you a signal to remind you about ‘Allergy’.
However, the material properties of pollen are too good to be abandoned based on this issue alone. Indeed, pollen grains are remarkably useful microcapsules that can be easily transformed into non-allergenic forms and are excellent candidates to build plastic replacements.
We have to study and find a way to transform their shape with eco-friendly processing. Pollen grains are microscale capsules that are produced by plants and have unique material properties that make them ‘practically indestructible’1. The outer coating of pollen shells is composed of sporopollenin, which is considered the diamond of biopolymers. It is possible to remove the allergy-causing proteins of the pollen, in order to leave the durable sporopollenin shell in the form of a safe, non-allergenic hollow microcapsule. Towards this goal, Dr. Nam-Joon Cho and his scientific team recently developed a very simple and affordable method (similar to traditional soap-making) to transform super-strong pollen grains into soft, flexible building blocks2.
Using industry manufacturing strategies, these pollen-based building blocks can be easily turned into a wide range of useful materials. Based on further scientific investigations, it will be possible to transform pollen-based building blocks into useful materials including sponges, wrapping-sheets, and polymer gels. Combined with the power of 3D/4D printing, there are nearly limitless options to develop and manufacture natural pollen-based materials that could replace non-natural plastics in the near future3.
Moreover, pollen is naturally produced by plants in excessively large quantities in order to ensure reproductive success, and the vast majority of pollen grains are left unused. All of these advantageous features make pollen highly interesting candidates for the future production of renewable, abundant, eco-friendly, safe, and affordable new types of bioplastic: Sporoplastic.
References
- Birks, H. J. B., Birks, H. H. & Ammann, B. The fourth dimension of vegetation. Science 354, 412-413 (2016).
- Fan, T. F. et al. Transformation of hard pollen into soft matter. Nat Commun 11, 1449, doi:10.1038/s41467-020-15294-w (2020).
- Cho, N. J. https://devicematerialscommunity.nature.com/users/367330-nam-joon-cho/posts/62264-pollen-an-immediate-solution-from-nature. (2020).
Dr. Nam-Joon Cho, is a MRS-Singapore Chair Professor at the School of Materials Science and Engineering, Engineering in Translational Science, at the Nanyang Technological University in Singapore. He can be contacted at E-mail: njcho@ntu.edu.sg
Image Credit: Nam-Joon Cho, Engineering in Translational Science Group
