Anahita Kodali, Life Sciences, News, Spring 5/3/2020
Figure 1: Blood clots when a blood vessel is damaged. First, platelets get activated to plug the hole and signal for more platelets and other cells to get involved in the clotting process. As other cells arrive at the point of damage, proteins in the blood (called clotting factors) signal chain reactions to create fibrin, which helps clotting by tangling with the platelets and creating a strong net that stops blood flow. Finally, other proteins and cells make sure that clotting does not spread more than it needs to4.
Scientists have identified several cells that are signaled for by platelets and that are found in clots. Here, we see erythrocytes (in the red regions) and plasma mixed with leukocytes (in the paler regions).
Image Source: Wikimedia Commons
Sometimes it feels like a cut bleeds for far longer than it should—especially after a hard fall off a bike or from slicing a finger open while cutting up vegetables. Regular Band-Aids never seem to be able to stop the bleeding, and pressing a thicker piece of cotton down on the cut until it stops feels like an eternity.
Now, researchers from the National University of Singapore and Zurich’s Swiss Federal Institute of Technology have created a solution: bandages that promote quick blood clotting, repel both blood and bacteria, and can be easily removed without reopening the wound. While trying to create a coating for medical devices that would repel blood, author Choon Hwai Yap’s team stumbled across a combination of silicone and carbon nanofibers that, in addition to being extremely hydrophobic (repelling water and therefore also repelling blood), also helped to boost blood clotting1. They sprayed the material onto cotton and used heat to apply the cotton to rats, finding that adhesion of the bandage promoted production of fibrin, a key protein that aids in clotting (see Figure 1). The cotton pads also stayed dry, which meant that when they were removed, the cuts were undisturbed, preventing further damage to the area. The team then tested if bacteria would be able to get through the cotton. The team applied a solution containing the bacteria Escherichia coli to cotton pads, and they found that the solution could not stick to the material. Thus, they were able to confirm that their coating would also prevent bacteria from entering wounds2.
In an interview with Scientific American, Yap explained that these bandages could be used in emergency situations like serious car crashes or war zones because in these situations, it is imperative to minimize blood loss and to keep wounds clean1. In addition, these bandages have the potential to be used in every-day scenarios too. People with bleeding disorders, who have disorders that prevent their blood from clotting properly, could use these bandages at home when they get cut, allowing for more travel time to get a hospital3.
While this product is extremely promising, Yap cautioned that there still needs to be more research done in order to understand exactly why the bandages were able to work the way that they did. They have huge potential on the market, especially because they are relatively inexpensive to produce1. With more time and research, hopefully these bandages will become the norm, both in homes and in hospitals.
Bibliography
[1] Kramer, J. (2020, April 1). New Bandage Repels Blood and Promotes Clotting. Scientific American.Retrieved from https://www.scientificamerican.com/article/new-bandage-repels-blood-and-promotes-clotting/
[2] Li, Z., Milionis, A., Zheng, Y. et al. Superhydrophobic hemostatic nanofiber composites for fast clotting and minimal adhesion. Nat Commun 10, 5562 (2019). https://doi.org/10.1038/s41467-019-13512-8
[3] Kahn, A. (2018, February 26). Bleeding Disorders. healthline. Retrieved from https://www.healthline.com/health/bleeding-disorders
[4] Pichardo, G. (2020, January 20). Blood Clots – How They Form and Common Causes. WebMD. Retrieved from https://www.webmd.com/dvt/blood-clots#1