From the `Scientists for the New Century' lecture delivered by the Zeneca lecturer in analytical sciences to the Royal Institution
SCIENCE AND technology now dominate nearly every aspect of our lives. But what could we say has been the greatest scientific achievement of our century? The 20th century has been an epic phase of discovery in which the fundamental scientific principles laid down in the centuries before have been refined and redefined, and our description of nature is almost complete.
If honest, most scientists would come to the conclusion that the most fundamentally important scientific revolution of the 20th century is due to the development of the quantum theory, which reduced the mystery of matter to a few postulates. The standard model created has been uniquely successful in predicting the properties of everything from tiny quarks to the behaviour of huge stars.
Although the quantum theory is the most fundamental revolution in this century, it is not the most tangible scientific revolution for the man in the street. That honour goes to two other great revolutions, which were facilitated directly by the quantum revolution.
The first began in 1948 with the very first transistor. This was a quantum mechanical device that performed a simple function - altering an electric current and allowing one circuit to switch another on and off. This device formed the basics of modern electronics and heralded the birth of the microelectronic revolution. The integrated circuit had been born, the last requirement for the computer.
Early computers were approximately 50 billion times slower than today's computers. Today the smallest elements printed on the most advanced microprocessor chips are less than one millionth of a metre in length. This high degree of miniaturisation means that today's computers are able to perform tasks that were unimaginable even 10 years ago.
The second revolution was the genetic revolution that was announced to the world in 1953 by Francis Crick and James Watson. They discovered the rather important molecule, deoxyriboneucleic acid, or DNA. DNA demonstrated the way in which the molecule can unravel, replicate and then pass on the genetic information contained within it.
So. The quantum revolution has, in turn, given birth to both the computer and the genetic revolutions, but what does it hold for the next century? Importantly, it represents the result of the natural synergy between the microchip, and the new biology and chemistry.
That marriage has given rise to a new generation of analytical instrumentation, called a laboratory-on-a-chip. The goal is to create microchips that do not solely perform electronic functions, but primarily perform chemical and biological functions.
Of the top 10 causes of death in the Western world, nine have a genetic contribution. By extracting the information contained within our own personal genetic blueprint we can in many cases infer susceptibility to both infectious and hereditary diseases. If we can make our instrument small, the cost of making it should be much less. We shall need much smaller amounts of sample in our analysis. Using less material will reduce the cost per analysis. If our instrument is portable we can take it to the sample rather than bringing it into a laboratory. This will change the face of health care in the next century.
The past five to 10 years have demonstrated that we can create microchip devices that are capable of performing all sorts of chemical and biological analyses. The challenge over the next five years will be clearly to define the primary application areas, which we may as yet not even have identified.
In many ways the modern-day micro-technologist can relate to Gulliver's problems in Lilliput, but always concludes that in the realm of biochemical analysis, smaller is better.