Skin cancer is the most common form of cancer in Australia and New Zealand; two out of three Australians will be diagnosed with skin cancer before their 70th birthday. Melanoma, the most deadly form of skin cancer, is cancer of the cells responsible for producing melanin.
Melanin colours our skin, hair and eyes, and protects us from the sun’s harmful radiation. It is also found in our brains, but its function there is less well-understood.
If we want to understand how our bodies use melanin then it is important to understand the physical and chemical properties of melanin. This seemingly routine task has led to several surprises and mysteries.
One of these surprises is that it conducts electricity very well. Most of the conductors we encounter in everyday life are inorganic – either metals like copper or semiconductors like silicon. But there is a growing interest in making electronic devices using organic molecules.
Many biological systems communicate by sending electronic signals. For example, to turn the page of this magazine you must send an electrical signal from your brain, through your nervous system to the muscles you want to move. In many ways this is just like a computer controlling a robotic arm.
The analogy between biology and robotics has led many people to ask whether a computer could control a real biological arm, or...