Discovery

What on Earth??!

Everyday objects become strange when viewed under the high magnifications possible with an electron microscope, but the information gained can tell us a great deal.

These photographs were all taken with Victoria University's scanning electron microscope (SEM). An image is obtained by bouncing an electron beam, which is negatively charged, off the solid surface of an object. The electrons are drawn into a detector containing a positive charge and are displayed on a screen. Magnifications of up to 100,000 times are possible, and the SEM is useful for viewing both biological and non-biological samples.

Biological samples are frequently treated with chemical fixatives so their structure remains as it was in the live state. These are then dehydrated using alcohols and dried. If the sample doesn't have any water, it can be mounted straight onto an aluminium stub.

Often samples are coated with a fine layer of gold -- four-billionths of a metre thick -- to reduce the build-up of electrons which can cause image distortion.

Teeba Lundy, Victoria University EMF

Teeba Lundy, Victoria University EMF