2.7 Silver nanoparticles: a case study in cutting edge research

Alvin Orbaek, Mallam Phillips, Dr. Mary McHale, Prof. Andrew Barron,

Objective

To gain an insight into nanotechnology, what it is and how it can be useful, using silver nanoparticles as an example. We will look at what exactly nanoparticles are, see how they are made, and how they can be characterized.

The characterization technique involves Ultra-Violet and Visible spectroscopy, so we will look briefly into the interaction of the nanoparticles and light, which will hopefully help you gain an appreciation for one of the special aspects of nanotechnology.

When making the nanoparticles we will do a time study allowing us to graph the spectroscopic response - which will show the nature of the particle as it grows, i.e., ripens. We can use some data to calculate the size of the nanoparticle at the beginning and at the end of our experiment.

Background

What is nanotechnology?

Nano is the ancient Greek word for dwarf. In scientific terms it has been used to identify length scales that are one billionth of a unit. This is typically a meter and so you often here things that are nanometers in size. In terms of nanotechnology it has been defined as anything that has a unique property or function resulting from the size of the artifact being in the nano regime, and that the size regime is between 0.1 and 100 nm. This size range is rather broad; encompassing simple molecules to more complicated molecules like enzymes. However, these items can be looked at from many points of view, from a chemist that considers molecules, to that of an engineer that would look at how each of the molecules interacts in the bigger system and creates new materials from these building blocks. For this reason there are many disciplines that are interested in the study of nanotechnology such as Chemistry, Physics, Engineering, Biological sciences, Material Sciences, Computer Science and many more besides. For this reason nanotechnology is not a strict discipline and many people use their skills and backgrounds from other areas to contribute to research in this particular field.

Why care about nanotechnology?

There are many effects that occur at the nanoscale that we do not notice on a larger macro scale. Most of nature actually works at the nanoscale, and by understanding the forces that are at work using knowledge from chemistry, physics and engineering one can better understand the working of organic life. Enzymes are very large molecules that are too large to consider in terms of chemistry alone, other effects come into play In order to understand the full picture we need to borrow from physics and computer modeling to gain a better understand of what is happening.

There are many effects that occur at the nanoscale that we do not notice on a larger macro scale. Most of nature actually works at the nanoscale, and by understanding the forces that are at work using knowledge from chemistry, physics and engineering one can better understand the working of organic life. Enzymes are very large molecules that are too large to consider in terms of chemistry alone, other effects come into play In order to understand the full picture we need to borrow from physics and computer modeling to gain a better understand of what is happening.