Electrophoresis is one of those tools that is central to almost everything you do in a lab. The ability to quickly load and analyze samples accurately is imperative to productive research. Because of this, our lab has been using the Criterion Precast System from BioRad. This system uses pre-cast polyacrylamide gels that are available in a wide variety of gel types. I generally use the 5% TBE Acrylamide gels, but BioRad also offers SDS-PAGE, Native PAGE, IEF, Zymogram and TBE-Urea gels. This extensive selection of gel types, each available with different percentage resolving gels, allows for rapid and accurate sample analysis.
The Criterion Precast System is an improvement over other gel systems in many ways, probably the most important of which is that the system itself is leak-free, unlike some of the other systems that I have used in the past. Also, the buffer is filled in each compartment of the tank separately - so if you are running one gel, you only fill one chamber, thus using half the amount of buffer. The gels themselves come with 12-, 18- or 26-wells, with the 12-well comb having two extra smaller wells for standards or markers. Prep-well and IPG-well (designed to hold immobilized pH gradient strips) gels are also available. There are even empty cassettes that allow users to pour gels to their own specifications. Each well is numbered and there are sample guides that, if needed, can be used to increase the ease of loading samples. In addition, the 12- and 26-well gels fit with multichannel pipettes. Gel information is printed on each gel, taking the guesswork out of expiration.
Once run, the gels are easily opened and removed, as the opener is located on the lid of the gel box. No more misplacing the tool! The gel comes out of the cassette easily, having a “J-foot” which allows the gel to lay flat without trimming. But the system does come with its drawbacks, the most serious of which is the cost of the pre-cast gels; they run about $12 each. It’s also important to be sure and store the individually wrapped gels in the proper orientation or they will dry out.
Overall, the BioRad Criterion Gel System is an improvement in gel electrophoresis. The convenience of pre-cast gels, larger gel size and multichannel loading capabilities allow for rapid sample analysis. The results are clear, sharp bands on gels that are publication quality.
Karrie Comatas
Research Technician II
Duke University