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This Startup Floats a Biomimetic Solution to Microplastic Pollution

PolyGone Systems has developed the world's first portable, affordable, low-maintenance microplastic collection device — aiming to help restore the health of waterways and marine life worldwide.

Microplastics, tiny plastic particles less than five millimeters in size, have become one of the most pervasive pollutants in our environment. They originate from the breakdown of a variety of sources — including larger plastic debris, synthetic clothing fibers and microbeads found in personal-care products. Microplastics are notoriously difficult to collect and remove from the environment.

Now found globally, from oceanic gyres to freshwater lakes, there are an estimated 171 trillion microplastic particles now floating in the world's waterways. Marine life, from plankton to whales, ingest these particles — causing physical harm, reduced feeding efficiency and death. Humans also consume roughly 5 grams of microplastics a week (equivalent to 50 plastic bags a year), raising concerns about potential inflammatory responses, endocrine disruption, and toxic chemical transfer.

The Plastic Hunter

New Jersey-based cleantech startup PolyGone Systems is on a mission to tackle marine microplastic pollution. Through its patent-pending technologies — the Plastic Hunter and the Artificial Root Filter — the company is capturing and analyzing microplastics in aquatic environments.

Launched in May 2021, PolyGone began as a research component of Nathaniel Banks’ and Yidian Liu's joint architectural thesis at Princeton University. Their research highlighted the dysfunctional plastic recycling industry and the millions of tons of plastic polluting the oceans annually. Shocked by the lack of infrastructure to remove microplastics from aquatic environments, the two proposed novel solutions for the collection and recycling of aquatic plastic waste.

“One of the main challenges in microplastic remediation is dealing with the tiny size of the particles,” co-founder and Lead Designer Yidian Liu explains to Sustainable Brands® (SB). “Most current plastic trappers in open water have limited capacity for particles smaller than one millimeter. Industrial water-treatment systems can handle smaller particles — down to a few micrometers — but they are very expensive to install and maintain, costing several hundred thousand dollars per module with long project timelines.”

In response, Liu and Banks developed the Plastic Hunter — a modular, affordable flotation frame that monitors, collects and removes microplastic debris from rivers and lakes. It uses arrays of biomimetic artificial root filters, made from hydrophobic silicone fibers that mimic aquatic plant roots, to effectively trap microplastics without disturbing ecosystems.

“Instead of relying on traditional mesh filtration, we invented a biomimetic filter called the Artificial Root Filter that mimics the fibrous structure of aquatic plant roots,” Liu explains. “These filters are made of thousands of silicone fibers which attract and trap small particles due to their hydrophobic properties. In fact, our recent experiments have shown that the smaller the particles, the more effectively they stick to our filter.”

The Artificial Root Filters can be easily attached to customized frameworks or the Plastic Hunter monitoring hub for efficient sampling and remediation. Plastic Hunter stations can be deployed in various water bodies to monitor microplastic pollution without requiring pumps or electricity. Analyzing the filter arrays provides valuable data on microplastic contamination in both urban and rural areas.

In highly polluted areas, large arrays of these filters can be deployed as a remediation measure. PolyGone’s design team provides custom support infrastructure and filter arrays to suit specific site conditions, making the Artificial Root Filter a scalable solution for diverse environments.

Image credit: Polygone Systems

PolyGone’s filters float on top of the water, targeting buoyant microplastics without disrupting the aquatic environment. These filters capture lighter microplastics while allowing fish and marine animals to swim freely underneath, providing a non-intrusive solution to pollution. To maintain the effectiveness of these filters, PolyGone has also developed an innovative cleaning solution.

"We've recently developed a large-scale cleaning device that shakes our filters back and forth to clean them,” Liu says. “By adding a specialized cleaning detergent, we achieve a 91 percent removal rate of microplastics from the filters. After cleaning, the filters are returned to operation, and the microplastic-contaminated water is processed through an additional filtration system."

The concentrated liquid plastic is then sent to Washington University, where PolyGone collaborates with Professor Tae Seok Moon — whose research focuses on upcycling microplastics using enzymes to break them down into other chemicals. While currently not highly profitable due to the small volume, this process provides a sustainable solution for preventing microplastics from re-entering the environment.

The ACUA pilot

PolyGone is embarking on its first large-scale industrial pilot program with the opening of the Microplastic Removal Pilot Project and the Educational Pavilion at the Atlantic County Utilities Authority (ACUA), which will open in September this year. This initiative is supported by a $1.9M grant from the NOAA Sea Grant Program Marine Debris Challenge Competition as well as a grant from the New Jersey Commission of Science, Innovation and Technology (NJCSIT) Pilot CleanTech Demonstration Grant Program.

“ACUA is one of the biggest wastewater treatment facilities in New Jersey, processing 40 million gallons of water and serving around 200,000 residents. When we first reached out to them, we didn't even have a field-ready device — just some lab-scale prototypes and experiment results,” Liu says. “They were incredibly supportive and eager to work with us, becoming our test partner to deploy our system at an industrial water-treatment facility. This year, after overcoming various engineering challenges, we are building the industrial pilot at the ACUA facility.”

“We are thrilled to see PolyGone’s microplastics removal project come to life,” said ACUA President Matthew DeNafo. “As an organization that embraces innovation, ACUA was eager to collaborate with the PolyGone team. The project may expand the role that wastewater-treatment facilities play in keeping our waterways clean, and we are happy to be a part of it.”

PolyGone’s technology will be deployed after the secondary water-treatment stage, targeting microplastics as the final contaminants. Using 720 filters, the goals are to assess the system's effectiveness by comparing upstream and downstream samples, identify the types of microplastics collected, and evaluate capture rates based on particle characteristics. PolyGone plans to generate a comprehensive report and assess the ease of system operation from the user's perspective.

“As the design lead of the ACUA pilot, I’m super excited to see it finally installed and ready for operation,” CTO and co-founder Nathaniel Banks tells SB. “The pilot represents a culmination of our company’s research on microplastic filtration and will hopefully serve as a benchmark for all future microplastic filtration pilots worldwide. I also am very excited to see how effective the filters perform in not only sequestering, but also recovering, microplastic contaminants from wastewater.”

Education and awareness

PolyGone integrates educational initiatives into all its pilot programs. In the Hudson and Delaware watersheds, they run community sampling programs and internships, training volunteers and students to take samples and analyze data. PolyGone also involves high school students in their projects. The upcoming pilot site at ACUA will educate visitors about the sources and impacts of microplastics on human health and wildlife. This pavilion will complement the water treatment education already offered at ACUA, which sees thousands of visitors annually.

Looking ahead, Liu and Banks — who made Forbes2024 30 Under 30 list for Social Impact — are seeking additional early adopters to join its 100 Plastic Hunters initiative, and focused on enhancing the scalability and accessibility of their technology.

"Our future plans include making the Plastic Hunter mobile for quicker deployment. This mobility will allow users to deploy and retrieve the system within a few hours — reducing risks from theft or extreme weather,” Liu adds. “Additionally, we are developing a smaller, portable cleaning device tailored for smaller monitoring groups — to simplify the cleaning process and make our technology more accessible."