New research takes step towards laser 3D printed medical electronics

Researchers at Lancaster University They have made a significant step toward laser 3D printing materials that could be used in surgical procedures to insert or repair medical devices. A team of scientists has developed a method for 3D printing flexible electronics with the conducting polymer polypyrrole.

According to the team, it proved that it is possible to 3D-print electrical structures in living organisms through testing with roundworms. The team believes that this process can be used to create patient-specific implants.

Dr. John Hardy, Seniro Lecturer in Materials Chemistry at Lancaster University and one of the lead authors on the 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. These approaches could revolutionize how we implant and 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.”

During the two-stage study, researchers used a Nanoscribe, a high resolution laser 3D printer to print an electrical circuit within a silicone matrix. This system is known as multiphoton fabricating, also called direct laser writing.

Dr. Hungyen Lin is Senior Lecturer in Electronic Engineering, Lancaster University, and Prof. Yaochun Shen is Professor in Electrical Engineering, at University of Liverpool, both co-authors on the study who led the 3D imaging work said: “We then saw an opportunity to fully characterise the fidelity of these printed structures embedded inside the matrix using a low-cost and high-speed optical coherence tomography process.

“The imaging technology recently developed at the University of Liverpool can capture an entire cross-sectional image of printed 3D objects in a single shot without the need of any scanning, making it attractive to many potential industrial applications such as offline quality inspection and in situ process monitoring. The information obtained from the 3D imaging could be used to inform the design, material choice and process optimisation of these print-outs rapidly and cost-effectively in the future.”

In vitro stimulation of mouse neurones by electronics was also demonstrated in the study, which is similar to deep brain stimulation using neural electrodes 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. We were able to induce neuronal responses similar to those observed in vivo using this method. Readily customised implants for a wide range of tissues offers both therapeutic potential and can be utilised in many research fields.”

The researchers printed conducting structures in nematode larvae using 3D printing. This demonstrated that the entire process (including ink formulations and laser exposure) 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 demonstrated that such technology could achieve the required resolution, safety, and comfort 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 project team believes that the results are a significant step in highlighting the potential of 3D printing to next-generation advanced materials technologies, particularly integrated electronics for bespoke healthcare applications.

You can find the study here.

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