MIT researchers develop biodegradable polymers to replace microplastics in beauty products

Researchers at the Massachusetts Institute of Technology (MIT), US, have developed a biodegradable material designed to replace microplastics commonly found in beauty products. The new material could also be used in food fortification and packaging applications. By targeting microplastic pollutants at their source, the MIT team aims to offer an eco-friendly alternative to the plastic beads currently prevalent in personal care products.

Microplastics, originating from sources such as plastic packaging, cleansers and cosmetics, have become a contributor to global pollution. The research, published in Nature Chemical Engineering, has the potential to mitigate this crisis by replacing non-degradable plastics with biodegradable materials for use in cleansers.

Linzixuan Zhang, the paper’s lead author, tells Packaging Insights: “For packaging applications, achieving higher mechanical strength and tailored degradation kinetics, such as prolonged stability or triggered degradation under specific conditions, is essential. The chemistry of polymer synthesis provides flexibility, allowing us to substitute monomers and optimize their combinations.”

“By systematically screening different compositions, we can identify formulations that deliver the desired performance characteristics for packaging applications.”

Sustainable alternatives 

The researchers present a novel degradable microparticle (MP) platform based on poly(β-amino ester) (PAE), offering an eco-friendly solution to replace non-degradable polyethylene microbeads. The PAE can degrade into sugar and amino acid derivatives.

Ana Jaklenec, a principal investigator at MIT’s Koch Institute for Integrative Cancer Research, says: “Polymers are incredibly useful and essential in countless applications in our daily lives, but they come with downsides. This is just one small part of the broader microplastics issue, but as a society, we’re beginning to acknowledge the seriousness of the problem. This work offers a step forward in addressing it.”

By modifying the composition of the material’s building blocks, researchers were able to tailor properties such as water resistance, mechanical strength and pH sensitivity.

The MIT team tested their particles in soap foam, where they outperformed conventional microbeads. The new particles were more effective at removing waterproof eyeliner from skin than existing cleansers, including those containing PE microbeads.

MIT team is developing environmentally friendly alternatives to microbeads in beauty products.“We wanted to use this as a first step to demonstrate how it’s possible to develop a new class of materials, to expand from existing material categories, and then to apply it to different applications,” says Zhang.

“As a novel material, scaling up the production of PAE microparticles from laboratory research to industrial levels presents challenges that require thorough evaluation. This includes assessing the reproducibility, cost-efficiency and feasibility of large-scale manufacturing processes, as well as ensuring that the material meets stringent commercial and regulatory standards for personal care applications.”

Expanding horizons

Beyond the personal care sector, the PAE particles could also have impacts on global nutrition. The study shows that the PAE particles can also be used to encapsulate essential nutrients, such as vitamins A, D, E, and C, as well as minerals like zinc and iron. 

The particles can protect the nutrients, preventing degradation under extreme conditions. Tests showed that after six months of storage at high temperature and humidity, more than 50% of the encapsulated vitamins remained intact.

The MIT team is preparing for a small human clinical trial to test the particles. The researchers are collecting data to support their application for regulatory approval from the US Food and Drug Administration to obtain the Generally Recognized as Safe classification.

The EU included synthetic polymer microparticles in a ban that went into effect in 2023. However, PAE has provided an alternative solution.

“The degradability of PAE polymers through simple hydrolysis within a reasonable timeframe positions them as a potential exemption from microplastics-related bans. Their compliance would ultimately depend on meeting the specific requirements outlined in the regulations. This inherent degradability aligns with sustainability goals and regulatory demands for environmentally friendly materials,” says Zhang.