Chemists devise revolutionary 3D bone-scanning technique

Chemists from Trinity College Dublin, in collaboration with RCSI, have devised a revolutionary new scanning technique that produces extremely high-res 3D images of bones -- without exposing patients to X-ray radiation.

The chemists attach luminescent compounds to tiny gold structures to form biologically safe ‘nanoagents’ that are attracted to calcium-rich surfaces, which appear when bones crack – even at a micro level. These nanoagents target and highlight the cracks formed in bones, allowing researchers to produce a complete 3D image of the damaged regions.

The technique will have major implications for the health sector as it can be used to diagnose bone strength and provide a detailed blueprint of the extent and precise positioning of any weakness or injury. Additionally, this knowledge should help prevent the need for bone implants in many cases, and act as an early-warning system for people at a high risk of degenerative bone diseases, such as osteoporosis.

The research, led by the Trinity team of Professor of Chemistry, Thorri Gunnlaugsson, and Postdoctoral Researcher, Esther Surender, has just been published in the leading journal Chem, a sister journal to Cell, which is published by CellPress.

The work was funded by Science Foundation Ireland and by the Irish Research Council, and benefited from collaboration with scientists at RCSI (Royal College of Surgeons in Ireland), led by Professor of Anatomy, Clive Lee.

Professor Lee said: “Everyday activity loads our bones and causes microcracks to develop. These are normally repaired by a remodelling process, but, when microcracks develop faster, they can exceed the repair rate and so accumulate and weaken our bones. This occurs in athletes and leads to stress fractures. In elderly people with osteoporosis, microcracks accumulate because repair is compromised and lead to fragility fractures, most commonly in the hip, wrist and spine. Current X ray techniques can tell us about the quantity of bone present but they do not give much information about bone quality.”

He continued: “By using our new nanoagent to label microcracks and detecting them with magnetic resonance imaging (MRI), we hope to measure both bone quantity and quality and identify those at greatest risk of fracture and institute appropriate therapy. Diagnosing weak bones before they break should therefore reduce the need for operations and implants – prevention is better than cure.”

In addition to the unprecedented resolution of this imaging technique, another major step forward lies in it not exposing X-rays to patients. X-rays emit radiation and have, in some cases, been associated with an increased risk of cancer. The red emitting gold-based nanoagents used in this alternative technique are biologically safe – gold has been used safely by medics in a variety of ways in the body for some time.
Professor Gunnlaugsson and his research team are based in the Trinity Biomedical Sciences Institute (TBSI), which recently celebrated its 5-Year anniversary. Professor Gunnlaugsson presented his research at a symposium to mark the occasion, along with many other world-leaders in chemistry, immunology, bioengineering and cancer biology.