Printing 3D medical implants with Riboflavin (B2)

3D printing technology – projected to be a $3 billion business by 2016 – is rapidly evolving, particularly in the medical space. Indeed, 3D printed orthopedic implants were recently fitted in Peking’s University Third Hospital in Beijing, while doctors at the Kyoto University Graduate School of Medicine in Japan successfully transplanted 3D printed bones into four patients with cervical spine (cervical) disc herniation.

Similarly, 3D printing tech helped doctors at the First Affiliated Hospital of Xi’an Jiaotong University repair a patient’s damaged skull in China, while researchers at the Huazhong University of Science and Technology used 3D printing technology to create living human kidneys.In September, scientists at Nottingham Trent University and Nottingham University Hospitals NHS (UK) Trust announced the development of an electronic smart pump to help victims of chronic heart failure.

This week, researchers from North Carolina State University, the University of North Carolina at Chapel Hill and Laser Zentrum Hannover confirmed that a naturally-occurring compound can be incorporated into three-dimensional (3D) printing processes to create medical implants out of non-toxic polymers. The compound is riboflavin, more commonly known as vitamin B2.

“This opens the door to a much wider range of biocompatible implant materials, which can be used to develop customized implant designs using 3D printing technology,” explained Dr. Roger Narayan, senior author of a paper describing the work and a professor in the joint biomedical engineering department at NC State and UNC-Chapel Hill.

The researchers in the above-mentioned study focused on a 3D printing technique known as “two-photon polymerization,” as this method can be used to create small objects with detailed features – such as scaffolds for tissue engineering, microneedles or other implantable drug-delivery devices.

Essentially, two-photon polymerization is a 3D printing technique for making small-scale solid structures from many types of photoreactive liquid precursors. The liquid precursors contain chemicals that react to light, turning the liquid into a solid polymer. By exposing the liquid precursor to targeted amounts of light, the technique allows users to “print” 3D objects.

Two-photon polymerization has its drawbacks, however. Most chemicals mixed into the precursors to make them photoreactive are also toxic, which could be problematic if the structures are used in a medical implant or are in direct contact with the body. Nevertheless, researchers have now determined that riboflavin can be mixed with a precursor material to make it photoreactive. And riboflavin is both nontoxic and biocompatible – it’s a vitamin found in everything from asparagus to cottage cheese.

As we’ve previously discussed on Bits & Pieces, the DIY Maker Movement has been using Atmel-powered 3D printers like MakerBot and RepRap for some time now. However, 3D printing has clearly entered a new and important stage in a number of spaces including the medical sphere, architectural arena, science lab and even on the battlefield.