Trans-Blot Protein Transfer System from Bio-Rad

There are a number of options available for transferring proteins in Western blotting. A semidry system is a fast and efficient method of transferring small to mid-range proteins and a wet system is great for larger proteins and protein complexes. The downside for wet transfer is the time that it normally takes. Usually for larger proteins, overnight transfer is recommended. Now, the TransBlot Protein Transfer System combines the efficiency of the standard wet blotting chambers with the speed of the bulkier semidry systems.

At first glance, the TransBlot system from Bio-Rad looks like any other wet transfer chamber. However, instead of the standard wire electrode, the TransBlot uses plate electrodes to allow for a higher, more even current. Because of this, proteins are transferred at a greater speed and efficiency. The optional super cooling coil allows for transferring at 200 volts without overheating the apparatus. Because the coil requires running water through it, I would recommend not using the coil in order to free up the tap. To keep the transfer cool, set it up in the cold room.

Although the system is very efficient for transferring large proteins, I would still recommend transferring proteins bigger than 160 kd at 30V overnight and then at 200V for another hour in the morning. If this method is used, be sure to use PVDF membrane to prevent protein loss. As with any other method, optimization is needed. There is a good trick to conserve buffer, however. Fill three 50ml tubes with water and float them in the chamber. That way 150ml of buffer is conserved with each run. Not a big saving but saves on buffer making time.

There are some downsides to the setup. For one, the blot holders are not very comfortable. They have a flimsy feel to them and are annoying to use with thicker gels. It is also not always easy to load the gel sandwiches into the chamber. It would also be nice if there were an easy way to drain the buffer out of the chamber. The only way to do this now is to actually pick up the unit and tip the whole chamber. It is very hard to recycle the buffer after the run.

I have been using this system at least three times a week for about one and a half years now. I have used it to transfer four minigels (8 X 8cm) or two midigels (8.7 X 13.3cm) at a time. Because the system does relatively rapid transfer at high efficiency, it allows for relatively narrow bands. This results in very high quality Western blots.

Overall, the TransBlot gel transferring system is a great solution for protein transfer. It is versatile enough to transfer a wide variety of gel and protein sizes at high efficiency. The electrodes are very sturdy and are built to last, making the chamber easy to clean. The speed and efficiency of transfer make the TransBlot an ideal solution.