Research laboratory

Analysis instruments

Devices for electrophoresis on agarose gelZoomZoom
© Nicole Catellier, Cinémanima

Devices for electrophoresis on agarose gel

The functioning of the electrophoresis device is based on the fact that when placed in an electrical field, electrically charged molecules migrate at different speeds depending on their size. Hence, in electrophoresis on agarose gel, negatively charged molecules of DNA and RNA can be separated according to their size by applying an electrical field. The separation is done through a porous matrix, such as agarose gel where the smaller molecules move more quickly through the gel’s pores and migrate further than the larger molecules. After the different fragments of DNA and RNA are separated, they are revealed under ultraviolet light by a fluorescent stain (ethidium bromide, for example) that is inserted between the DNA and the RNA.

Devices for electrophoresis on polyacrylamide gelZoomZoom
© Catherine Vamos

Devices for electrophoresis on polyacrylamide gel

The functioning of this device is based on the fact that when placed in an electrical field, electrically charged molecules migrate at different speeds depending on their size. Hence, in electrophoresis on polyacrylamide gel, proteins can be separated according to their molecular weight by applying an electrical field. In this specific case, the proteins are first denatured by heating in the presence of a detergent (SDS) that unfolds them and applies a negative charge. Separation of the proteins is done through an electrical field in a porous matrix of polyacrylamide gel, where the smaller molecules move more quickly and migrate further than larger molecules. Once the proteins have been separated, they can be viewed by direct staining (Coomassie blue, ponceau red, or silver nitrate).

ComputerZoomZoom
© Barbara Bélanger, Armand-Frappier Museum

Computer

A computer is a multifunctional device for the researcher. It stores information (text, images, databases) and can be linked to several databases connected to the Internet network. It therefore facilitates the analysis of many data such as DNA or protein sequences.

The computer can also be linked to an experimental device assisted by a computer program that allows the device to function automatically and analyzes and interprets the transmitted results.

Automatic DNA sequencerZoomZoom
© Nicole Catellier, Cinémanima

Automatic DNA sequencer

This device automates the DNA sequencing operation, a technique that consists in determining the exact order of nucleotides in a given DNA fragment. DNA sequencing has become indispensable in several areas of research. In medicine, for example, it can be used to diagnose genetic diseases and to attempt to find treatments for them. In biology, the study of DNA sequences has become an important tool for the classification of species.