3D Printing for Life Science Research
While the concept of 3D printing isn't new, the innovative technologies and cost reductions of the last few years have reduced the barrier to adoption which has allowed these tools to be more common in research, design and manufacturing settings. Inexpensive high precision hardware combined with the increasing usability of powerful CAD software has led to the development of communities of professional designers and amateurs alike who readily share, sell, and commission their skills and ideas. Imagination is quickly becoming the only bottleneck for what can be made with a 3D printer and researcher are even trying to bio-print functional tissues and organ systems.
There are two primary types of 3D printers utilized in small to medium sized business, filament extrusion printers, and liquid resin curing. Extrusion printers are fairly straight forward, a material, usually PLA (PolyLactic Acid), is melted and passed through an extrusion nozzle and laid down as a thin layer which solidifies almost instantly. Filament is then added through sequential layers until an object has been built up. This technique tends to be relatively high throughput and materials are inexpensive. Additionally, solid materials such as PLA or ABS can be replaced with bioinks using this approach that allow for living cells to be printed into scaffolds. Its drawbacks tend to be lower resolution (the “grain” between filament layers is visible) and the limitations of building strictly one layer at a time in one direction up the Z-plane.
The other common method is resin curing. By directing a laser on a building platform covered in liquid resin, a “pixel” of high resolution can be cured from the liquid state to a solid one. As the building platform moves away from the laser one step at a time along the z-plane, the pixels build upon each other and an object is formed. Laser curing allows for incredible resolution, smooth curves, and the ability to texture a surface. While print times are generally not significantly longer, the material costs can be in excess of 10 times the cost of PLA. The liquid resin can also be a mess to work with. Both systems have drawbacks, but can be used in tandem to maximize throughput and quality while minimizing cost.
The question I always get from people is “what do you actually use 3D printing for?” In our lab our most common uses are for building tools, creating novel parts for R&D projects and even the manufacturing of commercial products. Most biology labs will have a few standard pieces of equipment such as tube holders, forceps, spatulas, keck clips, etc. These are the small and inexpensive parts that we take for granted until one brakes, and we must wait days for a replacement. 3D printing is also great for that part that you can’t even find online or is really expensive such as a slide holder for your imager or a rack for your Falcon tubes.
Additionally, 3D printing is changing the way that we and many labs approach prototyping of new products as traditionally going from the design board to the first prototype could be an expensive and time-consuming endeavor. In the past, cardboard, wood, clay and even legos have been the go-to for rapid mock ups. However, 3D printing materials is quickly becoming the new standard as high resolution and exact dimensions can be obtained with micron precision rapidly and inexpensively which allows for faster development times. Once designed and uploaded to the printer, the actual fabrication time is freed up while the printer does the work. For example, Visikol has used its multiple 3D printers in this way to develop tissue holders and slide holders for custom drug discovery projects for use with its high content confocal imager.
Lastly, 3D printing can turn a profit. Many small companies stumble onto ideas for products after having to address their own need for something not readily available on the market. As an R&D department solves a novel problem, it becomes clear that others in the field are facing this same issue and would gladly pay for an inexpensive and customized solution. In Visikol’s case, rapid sectioning of tissues at the millimeter scale looked like a problem with either expensive or low-quality solutions. Therefore, we created the Visikol Mouse Brain Slicers in 1 and 2 mm section sizes. It took a couple prototypes and a few hours of CAD for designing but what we came up with was an inexpensive, durable and rapid solution for our problem, and our customers agree about its utility.
Written by: Ian MacCloud