Thinking inside the box: Small is beautiful
I have been spending some time reading about the marvellous advances made in medical science since my lifetime. I always had friends among medical men, and as a young man attended the lectures of William Hunter, the Garrick of medical orators, on anatomy and surgery. Medicine always seemed to me to be the most beneficent of professions, and if I had not discovered that my genius lay in the field of legislation—the practical branch of the medicine of the soul—I might have been happy to look back and account a life spent in the pursuit of medical knowledge an entirely worthy one.
I wanted to share with you my excitement at the progress offered up in medical treatments simply by a change in scale. A nanometre is apparently one billionth of a metre—that is 0.000000039 inches in the English measure of my day. For the sake of comparison, a molecule of water is one tenth of a nanometre wide. The ability to manipulate matter on this scale opens up amazing possibilities that were previously unheard of. In the first place, using tiny particles as ‘scaffolding’ to support a therapeutic drug allows that drug to be delivered across previously impermeable barriers within the body. It remains the active chemical in the drug that does the therapeutic work, but creating self-assembling particles of such metals as gold, which is not toxic to our bodies, promises to allow the delivery of the drug to the site where it is needed.
In the second place, operating on the nano-scale apparently changes the chemical and physical properties of matter, which itself opens up new possibilities for treatment. For instance, in my day it was known that silver possessed valuable properties which could help to combat infection in wounds. It turns out that nano-crystalline silver—tiny particles coated with silver—is many times more deadly to the microbes which cause infection than ordinary crystalline silver, and has collateral benefits including reducing the inflammation which can retard healing. Further, mirabile dictu, it seems that at the nano level, metals like gold become magnetic. This remarkable fact has been exploited to implant magnetically responsive nanoparticles in the organs of the middle ear to drive tissue vibrations in the amplification of sound. The implications for the treatment of deafness are truly exciting.
Yet further, nanoshells, infinitesimally small glass beads coated with gold, offer the opportunity to seek out and destroy cancer cells without harming the healthy cells by which they are surrounded. Having been guided to the cancer cells by a particular protein they contain, the nanoshells convert infrared light into heat and ‘cook’ the cancer cells, leaving the healthy cells intact. I have read that the currently available treatments for cancer, like chemotherapy, have awful side effects and impact on healthy cells as well as cancerous ones. The ability to seek and destroy only the malignant cells of the tumour would significantly reduce the pain involved in treatment, as well as promising to be much more effective.
I look forward to the realization of all these projects, which might prevent so much pain. What a time to be commencing on a career in medical research: new frontiers ready to be crossed, new discoveries to be made. I wish my friends Dr George Fordyce and Dr Thomas Southwood Smith were here to share my excitement, and to provide their tutelary guidance through the literature. In their absence, I am, I confess, tempted to expostulate upon these matters at almost infinite length, but I cannot wait to read about the possible uses of nanotubes, including scaffolding to promote new bone growth!
Your humble, but remarkably stimulated, servant,