Bio-Engineering can Leverage AM with the 3D-Bioplotter

Most engineers consider additive manufacturing to be a technology for building plastic, ceramic and metal parts. However, bio-engineers have are exploring the promise of 3D printing. Now major AM manufacturers are looking to make machines to support that market.

EnvisionTec's 3D-Bioplotter is one of the more polished and promising entries in the bioprinting market. With two model levels available, the 3D-Bioplotter is designed to meet the needs of both educators and industry at a competitive price point.

Currently, printers like the 3D-bioplotter can only build scaffolds from which other more advanced biological materials can be grown. While that might seem a bit disappointing, 3D bioprinting is opening up new opportunities for bio-engineers to develop their products in a manner that was difficult, if not unthinkable, only a decade ago. Within the coming decade, 3D-bioprinting is expected to mature significantly, growing into a viable part of the AM landscape. Some people have forecast that 3D-bioprinting might pave the way to bespoke therapies and possibly replacement tissues.

How the 3D-Bioplotter Works

EnvisionTec's 3D-Bioplotter builds its products in much the same way as a traditional 3D printer. However, instead of using plastics, metals or resins, the Bioplotter uses biologic materials to form a scaffold that will be used to grow more advanced cellular cultures.

Just like a traditional 3D printer, the 3D-Bioplotter can be fed a 3D model generated in a CAD program or from a CT scan. Users can slice and hatch a 3D model to define how it will be printed. That information is then translated to code and shipped off to the Bioplotter where the real work begins.

While prototype objects in the mechanical, architectural and civil worlds can be built from a single material, in the biological world it's rare that the desired objects have a uniform material. To meet that reality, the Bioplotter can print a model in 5 different materials making it suitable for more complex cellular assemblies.

This ability to jet different materials during a single build requires the 3D-Bioplotter to change print heads. It comes equipped with a CNC-like tool holder that can be programmed to change “print-heads” based on the material being extruded. Most bio-engineering builds favor porosity. This machine's ability to change print heads can also help alter the flow and spacing of successive print layers to give users greater control of their models.

The 3D-Bioplotter in Action:

According to EnvisionTec, the 3DBioplotter has mainly been used in academic settings. Bioprinting is quickly growing, so now start-ups from San Francisco to Shanghai are beginning to experiment with the technology.

Academic literature, provides a few quotes that highlight the bioprinters' stengths:

“Biomaterials capable of efficient gene delivery by embedded cells provide a fundamental tool for the treatment of acquired or hereditary diseases… Our study shows that [bioprinted] constructs can promote cell viability and release of therapeutic proteins, and clearly demonstrates their capacity for a dual role as scaffolds for tissue regeneration and as delivery systems for soluble gene products.”

-El-Ayoubi, Rouwayda, et al. "Design and fabrication of 3D porous scaffolds to facilitate cell-based gene therapy." Tissue Engineering Part A 14.6 (2008)

“Hydrogels with low viscosities tend to be difficult to use in constructing tissue engineering (TE) scaffolds… However, recent advances in rapid prototyping have allowed for a new technology called bioplotting to be developed, which aims to circumvent these inherent problems…This process allows plotting of various materials. TE scaffolds have been produced using a variety of materials including poly(ethylene glycol) (PEG), gelatin, alginic acid and agarose at various concentrations and viscosities.”

-Maher, P. S., et al. "Construction of 3D biological matrices using rapid prototyping technology." Rapid Prototyping Journal 15.3 (2009

“In this study, we fabricated strontium-containing mesoporous bioactive glass (Sr-MBG) scaffolds with controlled architecture and enhanced mechanical strength using a three-dimensional (3-D) printing technique. The study showed that Sr-MBG scaffolds had uniform interconnected macropores and high porosity, and their compressive strength was ∼170 times that of polyurethane foam templated MBG scaffolds… 3-D printed SrMBG scaffolds combined the advantages of Sr-MBG such as good bone-forming bioactivity, controlled ion release and drug delivery and enhanced mechanical strength, and had potential application in bone regeneration.”