A colorful, sustainable solution for 3D printing

Researchers at Pacific Northwest National Laboratory (PNNL) have developed seaweed-based inks and materials for developing colorful 2D and 3D shapes and models.

The innovation is called ArtSea Inks and Materials. The set of vivid inks—think a futuristic upgrade from yesteryear’s eight-pack of Crayola crayons—was developed using seaweed solutions bolstered with pigments that give it a lustrous finish. ArtSea Inks and Materials don’t require high heat or unsustainable fossil fuel-laden plastic materials to produce non-toxic, durable structures.

From biodetection to art and education…and beyond

The roots of ArtSea Inks and Materials began with biodetection in mind—specifically, rapid detection and characterization of biological threats—using a combination of strengths in 3D printing, material design, tissue engineering, and host response.

“We’ve matched this expertise with the concept of 3D printing so we could, for example, develop a novel 3D printed human tissue array to study how harmful microbial pathogens can affect the tissue,” said Anne Arnold, the researcher who led development of ArtSea Inks and Materials. An example of such a pathogen is Bacillus anthracis, the causative agent of anthrax and influenza.

Beyond biodetection, the team soon discovered that ArtSea Inks and Materials could be used for a wider array of purposes, such as creating art, providing models for science, technology, engineering and mathematics use, or developing 3D printed medical models.

“We’ve discovered it’s a very versatile innovation that reaches beyond biodetection,” said Sara Hunt, PNNL commercialization manager. “The technology can be extended to larger medical corporations, schools, even the “DIYers’ who enjoy making their own creations.”

ArtSea Ink and Materials, developed using a PNNL internal funding program that is designed to foster innovation and creativity, were recently featured in Nature after findings were published in the journal ACS Omega.

Alginate and mica—the secret sauce

ArtSea Inks and Materials are referred to as “bioinks” because they are made from alginate, a low-cost, widely available, and non-toxic sodium salt extracted from brown seaweed. The material forms a stable gel without the need for excessive heat.

To create the bioink, the scientists infuse the pigments, called mica colorants, into the algal extract—imparting vivid colors.

The algal/mica combination is dissolved in water and then combined with a solution of calcium chloride. The positively charged calcium ions meld with negatively charged portions of various polymer strands, forming a viscous tunable “gum” that offers a balance of stiffness and workability to form stable 3D structures.

The solution is then extruded from a syringe-like applicator to form colorful, finely detailed 2D and 3D structures. It eliminates the need for complex software or hardware maintenance of a 3D printer.

The bioinks also can be formulated to any color, including metallic and pearlescent colors, as well as glow-in-the-dark inks. ArtSea Inks and Materials can be used to create representations of biological materials and models as well as incorporate mammalian and bacterial cells into the bioink. The results, for example, could provide structures that illuminate the lantern of a firefly’s abdominal region for studying the internal workings of that species or depict different regions in a human brain for anatomy lessons in high school science classes.