Light & Fluorescent Microscopy

Standard widefield microscopes are available for optical light and fluorescent microscopy. The instruments available include a stereomicroscope, an upright light microscope and an inverted light microscope. These instruments allow imaging of whole organisms, tissues and cells, including those on a Petri dish, essentially covering the resolution range from millimeters to microns.

The light microscopes in Bioimaging allow observation of material in both colour (RGB) and black and white (monochrome) using high-end digital cameras.

Colour is used for imaging standard material such as plants and insects, or for histochemical or GUS staining. Monochrome imaging is used primarily for fluorescence microscopy to maximise the number of photons captured by the camera in potentially low light conditions. Normal brightfield imaging can also been done in black and white if required.

A variety of optical techniques are available for imaging with brightfield such as Differential Interference Contrast (DIC) and Phase Contrast. Users can be trained on these techniques at any time.

Fluorescent microscopy uses a high energy light source, such as a mercury bulb, to excite electrons in a fluorescent molecule, e.g., GFP. As the electron returns to its lower energy state, the excess energy is released as a slightly lower-energy photon with some of the energy lost as heat.

To determine the compatability of of fluorophores and available filters, it is helpful to look at the excitation and emission spectra of the molecule. The spectra are available in catalogues and with the equipment; however, it is easiest to look up on dedicated spectraviewers on the internet, a couple of which are listed on the links page. Available filters are listed on the equipment pages for the relevant light and confocal microscopes.

It is required that users have training on the instruments and in sample preparation for many techniques in Bioimaging. Please contact Bioimaging staff for further information regarding specific techniques.