Nanomedicine could outdo surgery
Nanoparticles programmed to dispatch drugs to specific parts of the body could make surgery a thing of the past, writes David Tan
Imagine swallowing a pill of tiny molecular robots that can hone in on any injured part of your body and perform repairs. In 1959, the Nobel Laureate Richard Feynman predicted that we would one day be able to "swallow the doctor" to heal ailments from inside our bodies.
Today, nanotechnology is bringing the dream of that pill closer to reality. Medicines are being developed to be just like the small seeds of the burr plant, covered in tiny hooks that cling onto your socks as you walk through the grass. Submicroscopic nanoparticles are designed to bind tightly to specific targets within the body and release drugs slowly and steadily.
"If you put 1,000 nanoparticles side by side they are about the width of a human hair," says Dr Juliana Chan, adjunct assistant professor at the Nanyang Technological University (NTU) in Singapore.
Hong Kong University Professor So Kwok-fai specialises in neuroscience and has developed a nanoparticle in collaboration with MIT to support regeneration after nerve damage. Explaining why this treatment is needed, So says: "The central nervous system is unable to repair itself because the nerve microenvironment does not support neuron regeneration."
The nanoparticle is made by linking amino acids, the building blocks of protein. When the nanoparticles come in contact with blood, they self-assemble into a nanofibre scaffold. This scaffold can bridge gaps in damaged tissue and provide a framework for nerve regeneration. For example, So has tested his formulation on laboratory animals to repair optic nerveS, resulting in functional vision.
An unexpected finding was that the nanoparticles were able to stop bleeding, a major problem during neurosurgery. During a surgical experiment, So's team was surprised to find that the laboratory animal did not bleed after the nanoparticle solution was applied. They realised that the nanoparticles were an effective means to stop bleeding, which leads to faster recovery after surgery. "An analogy would be like beavers building a dam with wood instantaneously so the flow of water can be stopped right away," says So.