The U.S. military has been looking for ways to increase its technological advantage through the use of biomaterials, and now they may have found a way to do just that.
In an announcement by US Army Combat Capabilities Development Command or “DEVCOM,” a US Army-sponsored study by Texas A&M University has led to a development of an invention called a “centrifugal microfluidic platform,” which the Army says could have a major impact on the field of bioelectronics by accelerating the discovery of new biomaterials.
“[It’s] all about taking promising synthetic biology research and applying it to military-relevant environments and systems,” Army chemical engineer, Dr. Justin Jahnke, said in a press release by DEVCOM. “There’s a lot more that we can do to engineer organisms than was possible even five or ten years ago, and it has really opened up doors for developing new ways of making materials and understanding how organisms behave in the field.”
BACKGROUND: Biomaterials, Where Biology and Technology Meet.
Historically, the US Department of Defense (DOD) has invested in research focusing on medical and chemical biology projects.
However, in the 2018 National Defense Strategy, the development of cutting-edge biomaterials was mentioned as a major modernization priority to maintain an advantage in the great power rivalry with China and Russia.
“It [biotechnology] is a disruptive technology that will change warfighting and provide dominant capabilities to the department across multiple domains,” Michelle Rozo, Assistant Director for Biotechnology at the Office of the Undersecretary of Defense for Research and Engineering, said during a 2020 webinar hosted by the National Defense Industrial Association. “One of the opportunities here for the Department of Defense is its potential to provide new sources of critical materials.”
In 2020, US Army Research Labs launched the Transformational Synthetic Biology for Military Environments Essential Research Program or TRANSFORME. DEVCOM’s primary focus with TRANSFORME is to “harness biology’s capacity for custom material production & modification of material properties.” The program also examines factors that will inform and shape policy and ethics of the use of synthetic biology products.
ANALYSIS: Problems in the Development of Synthetic BioMaterials
The development of new synthetic biological materials is dependent on the identification of microorganisms with desirable characteristics, such as adhesion to particular target materials.
Researchers employ a technique known as biopanning to discover the right microorganisms. The process distributes cells from a cellular display library onto a target substance of interest, then washes the material to remove all remaining non-target cells. This procedure is repeated until only the intended cells—those with a high degree of connection to the target substance—remain.
In biopanning, the rinsing process is especially crucial in isolating the sought-after cells. Researchers may end up washing away the wanted peptides with those that have a poor affinity if they don’t use enough shear stress. However, if researchers employ too much shear stress, they may inadvertently wash away the intended peptides.
A rotating shaker is the primary method used for biopanning, however, it provides little control over shear force on the cells when bound to the substance. Researchers often have to play around with trial and error to separate moderate binders from high-affinity binders for certain purposes.
“When we use the rotating shaker, we don’t actually know the measured force that we’re putting on the cells,” said Deborah Sarkes, Army research biologist. “We just have to trust that the rotation speed is going to be consistent from experiment to experiment in terms of creating the necessary shear force.”
OUTCOME: New Research Comes Up With a Breakthrough Solution
To overcome many of the challenges inherent in existing biomaterial production systems, US Army Research Labs partnered with Texas A&M University to develop a tool that uses centrifugal force to remove free cells.
Scientists can precisely regulate the amount of centrifugal force with this device simply by changing the spin rate when they place the microfluidic channel on a spin coater platform.
“The novelty of this device is the level of control that we can achieve over the shear force using centrifugal force,” said Dr. Sarkes. “With this device, we can achieve a much higher level of shear force and actually isolate binders more precisely than we could before.”
The centrifugal microfluidic platform was validated in an experiment that successfully isolated peptides from a bacterial display library that only binds to gold, indium tin oxide, or both. Scientists were able to coat the gold- or ITO-printed letters on a glass panel with such a high degree of specificity that when stained, the bound cells were clearly visible.
Army Research Labs says it plans to now use the new tool to find target materials to enhance technologies in RF electronics, next-generation combat vehicles, Soldier lethality, and more. New biomaterials could also be integrated with other developing technologies. For example, the Army’s recent development of AI-enabled programable fibers for new military uniforms.
“Ultimately, new materials like these will give our future Soldiers new capabilities and platforms that will help them win on the battlefield,” said Jahnke. “At the end of the day, we at the Army Research Laboratory want to make sure our Soldiers have all the advantages that science and technology can provide.”