Thu, 16 March, 2023
The Additive Manufacturing Innovation Centre – a strategic partnership between Lancaster University and TWI – is part of a team of researchers that has taken a major step towards the creation of 3D laser-printed materials that could be used in surgical procedures to implant or repair medical devices.
Led by Lancaster University, the scientists have developed a method of 3D printing flexible electronics using the conducting organic polymer polypyrrole (PPy), showing that it is possible to directly print these electrical structures on, or in, living organisms (roundworms).
Currently at the proof of concept stage, the team believes that, when fully developed, this type of process has the potential to print patient-specific implants for a variety of applications, including real-time health monitoring and medical interventions such as treating epilepsy or pain.
Dr John Hardy, Senior Lecturer in Materials Chemistry at Lancaster University, and one of the lead authors of the associated study, said “This approach potentially transforms the manufacture of complex 3D electronics for technical and medical applications, including structures for communication, displays and sensors, for example. Such approaches could revolutionise the way we implant but also repair medical devices. For example one day, technologies like this could be used to fix broken implanted electronics through a process similar to laser dental/eye surgery. Once fully mature, such technology could transform a currently major operation into a much simpler, faster, safer and cheaper procedure.”
In a two-stage study, the researchers used a Nanoscribe (high-resolution laser 3D printer) to 3D print an electrical circuit directly within a silicone matrix using an additive process. This demonstrated that these electronics can stimulate mouse neurones in vitro; similar to how neural electrodes are used for deep brain stimulation in vivo.
Dr Damian Cummings, Lecturer in Neuroscience at University College London, a co-author of the study who lead the brain stimulation work, said “We took 3D printed electrodes and placed them on a slice of mouse brain tissue that we kept alive in vitro. Using this approach, we could evoke neuronal responses that were similar to those seen in vivo. Readily customised implants for a wide range of tissues offers both therapeutic potential and can be utilised in many research fields.”
In the second stage of the study, the researchers 3D printed conducting structures directly in nematode worms, demonstrating that the full process: ink formulations, laser exposure and printing, is compatible with living organisms.
Dr Alexandre Benedetto, Senior Lecturer in Biomedicine at Lancaster University, and another lead author of the study, said “We essentially tattooed conductive patches on tiny worms using smart ink and lasers instead of needles. It showed us that such technology can achieve the resolution, safety and comfort levels required for medical applications. Although improvement in infrared laser technology, smart ink formulation and delivery will be critical to translating such approaches to the clinic, it paves the way for very exciting biomedical innovations.”
The team believes these results are an important step in highlighting the potential for additive manufacturing approaches to produce next-generation advanced material technologies, in particular integrated electronics for technical and bespoke medical applications.
The next steps in the research and development are already underway, exploring the materials which can be printed in and the types of structures it is possible to print, and developing prototypes that can be showcased to potential end users who may be interested in co-developing the technology. The researchers believe the technology is around 10 to 15 years from being fully developed.
Their findings are reported in the paper ‘Creating 3D objects with integrated electronics via multiphoton fabrication in vitro and in vivo’, published in the academic journal Advanced Material Technologies.
The research was supported with funding from a variety of sources including: the Engineering Physical Sciences Research Council (EPSRC), the Biotechnology and Biological Sciences Research Council (BBSRC), the Medical Research Council (MRC), the Royal Society, the Wellcome Trust and Alzheimer’s Research UK.