Overview:

Continuous sensing of the ocean is a still-formidable task. Expendable, networked, free-drifting instruments are revolutionizing ocean observation, but these growing fleets of sensors present an environmental challenge and a necessary shift in how we think about the materials used in their construction. At present, most “biodegradable” plastics have limited biodegradation in cold, dark oceanic conditions and were designed and tested only in industrial composting facilities. More effort is needed to develop both sustainable materials and testing standards that accurately reflect in situ conditions in the ocean. Materials that facilitate rapid degradation of marine instrumentation under realistic environmental conditions would transform our ability to deploy swarm sensors at scale. Solving this problem requires the convergence of intellectually distinct fields and approaches, as well as the involvement of stakeholders that manage marine debris and end-users. Together, our team will innovate, test, and integrate biomaterials designed to rapidly degrade at end-of-life in oceanic conditions. First, we will develop a suite of novel plastic materials purpose-built for the marine environment by 3D printing living bacteria into the biopolymer polyhydroxyalkanoate (PHA), optimized with additives to supplement microbial metabolism. Second, we will modify existing marine instrumentation to produce a chamber for directly measuring the respiration of plastic materials in deep ocean environments. Finally, we will work with end users to prototype products designed to be deployed in the marine environment. Our overarching objective is to integrate sustainable materials into oceanographic instrument applications.

Intellectual Merit:

Our project embodies a Convergence Research approach by bringing together a team of microbiologists, materials scientists, engineers, and oceanographers from four academic institutions together with industry partners from the oceanographic instrumentation sector and government experts in marine debris management to facilitate more sustainable engagement with the ocean. For the first time, we will use knowledge about the metabolism of uncultured microbes in the ocean to enable smart design of PHA additives to be implemented by the bioplastic company Mango Materials. We will pioneer the embedding of live PHA-degrading marine bacteria directly into plastic materials by developing strategies for extending the viability of living cells in printed materials. The field-deployable respiration chamber developed as part of this project could set a new industry standard for testing materials used in the marine environment. The successful development of materials designed to rapidly degrade in seawater would transform multiple marine sectors, such as fisheries, and permeate wider industry applications where marine pollution by plastics is of major concern. In this way, the project has significant potential to synergize with other projects in Track E.

Broader Impacts:

Plastics are a $4-trillion industry; less than 1% are bioplastics. Our project will pioneer a novel approach to designing materials for the marine environment by explicitly considering the metabolism of microbes in the environment in which they are expected to biodegrade. Our five team leads identify as female or LGBTQIA, with experience engaging underrepresented groups in scientific research. Our Broadening Participation Plan will further broaden participation of under-represented individuals through recruitment of undergraduates at UCSB (an HSI) through the Society for Advancing Chicanos and Native Americans in Science (SACNAS) to do paid internships at Mango Materials. Under-represented students from other institutions will be recruited to URI through NSF-supported REU (SURFO) and EPSCOR (SURF) programs. Through a partnership with the UCSB BioPACIFIC Materials Innovation Platform, we will disseminate the results of this research to the next generation of material innovators through an annual summer school.