This inexpensive, safe, equipment was developed by the NCBE so that school students could carry out gel electrophoresis with DNA. It was awarded the coveted Millennium Product status by the Design Council in 2000.

ABOUT THE BASE UNIT

Gel electrophoresis is a key technique in modern biology. It is used to separate DNA fragments of different sizes. First, a gel is cast from agarose — a very pure form of agar, which is obtained from seaweed. At one end of the slab of gel are several small wells, made by the teeth of a comb that was placed in the gel before it set. A buffer solution is poured over the gel, so that it fills the wells and makes contact with the electrodes at each end of the gel. Ions in the buffer solution conduct electricity. The DNA fragments are mixed with a small volume of loading dye. This dye is dissolved in a dense sugar solution, so that when it is added to the wells, it sinks to the bottom, taking the DNA with it.

An electrical potential is applied across the gel. Phosphate groups give the DNA fragments a negative electrical charge, so that the DNA migrates through the gel towards the positive electrode. Small fragments move quickly through the porous gel — larger fragments travel more slowly. In this way the pieces of DNA are separated by size. The loading dye also moves through the gel, so that the progress of the electrophoresis can be seen.

After electrophoresis, the gel is stained with a harmless dye to reveal the DNA.

Electrophoresis modules

The Lambda protocol
Nature’s dice
Plant evolution PCR
Protein power!

Electrophoresis resources

Base unit
36 V mains transformer
Microcentrifuge
Micropipettes
Spare parts

Other DNA items

The Transformer protocol
DNA pendant kit
Double helix badge

DOWNLOADABLE PDFs

NCBE Price list
DNA safety advice (UK)