Laboratory Equipment and Instrumentation
Centrifuges are used for a variety of procedures, and we will typically be using them to separate particulate material (ex. cells, DNA) out of a liquid suspension. We will be working with microcentrifuges, tabletop centrifuges, and a high-speed centrifuge throughout the semester. Microfuges are used to spin down small samples in eppendorf (or microfuge) tubes, usually less than 1.5 ml. Much DNA and protein work is done using a microfuge, which can spin up to ~15,000 rpm. Lower speed tabletop centrifuges are used to spin down cells that are grown
in culture at speeds that are typically less than 3000 rpm. These centrifuges can hold tubes of 5-50 ml (or more with the appropriate adapters). 96-well plates can also be spun in these centrifuges, with the appropriate buckets and adaptors.
When working with any centrifuge (high-speed, tabletop or microfuge) it is important that you always balance the tubes before spinning. A tube of equal weight (same size and filled to equivalent volume with water) should be in the position diagonally across the centrifuge (see below).
Vortexers are spaced throughout the lab. You will use these often to mix solutions and to resuspend pellets.
Electrophoresis power supplies are used to run current across both DNA and protein gels.
Heating blocks are useful for incubating small volume samples at specific temperatures. For example, protein samples are routinely heated in sample buffer just prior to polyacrylamide gel electrophoresis.
The spectrophotometer is used to measure the concentration of molecules (ex. DNA, RNA, bacterial cells, protein) in a liquid solution.
Biochemi Digital Detection System
This system has a CCD camera for taking pictures of DNA in agarose gels and proteins detected by immunoblot. We use this system to verify that our DNA and proteins are present and the correct size.