Handheld 'pen' to allow doctors print stem cells during surgery

Australian researchers have designed a small, lightweight 3D printing pen that surgeons can hold with their hand and draw human stem cells just when they need it -- during surgery.

Using a hydrogel bio-ink to carry and support living human stem cells, and a low powered light source to solidify the ink, the pen delivers a cell survival rate in excess of 97 percent, the study said.

Three dimensional bioprinters have the potential to revolutionise tissue engineering -- they can be used to print cells, layer-by-layer, to build up artificial tissues for implantation.

But in some applications, such as cartilage repair, the exact geometry of an implant cannot be precisely known prior to surgery.

This makes it extremely difficult to pre-prepare an artificial cartilage implant.

The new device could allow the surgeon unprecedented control in treating defects by filling them with bespoke scaffolds.

The device was developed out of collaboration between Australian Research Council (ARC) Centre of Excellence for Electromaterials Science (ACES) and researchers and orthopaedic surgeons at St Vincent's Hospital, Melbourne.

Professor Peter Choong, director of orthopaedics at St Vincent's Hospital Melbourne, developed the concept with ACES director Gordon Wallace.

The device, described in the journal Biofabrication, is small, lightweight, ergonomic and sterilisable. A low powered light source is fixed to the device and solidifies the inks during dispensing.

The team designed the "BioPen" with the practical constraints of surgery in mind and fabricated it using 3D printed medical grade plastic and titanium.