Sunday afternoon at the 2009 Biophysical Society meeting in Boston, Massachusetts, I found myself wandering the aisles of the exhibit hall with an odd sense of “high-throughput patch clamping” déjà vu. Every row I walked down had at least one company demonstrating the latest in automated patch clamping instrumentation. Apparently, these automated approaches for patch clamping cells are becoming more and more common since their initial introduction in 2001 and here in Boston six different companies are showcasing their approaches. The systems range from being “adaptable” – capable of patching a range of cell types — to “high-throughput”— capable of patching up to 48 individual cells in 48 wells in a single run in their current versions but with a 96-patch system in the works.
For me this information was simply amazing. You see I have always thought there is a limit to what can be automated in the lab. Oh sure, liquid handling applications and reaction set up have benefited incredibly from robotic automation and many parts of microscopy are now automated as well. But patch-clamping – where a very narrow tube must be carefully placed on a single cell to measure the conductance of ions through a channel in response to a stimulus — is different. I can still recall one of my earlier research endeavors where our group was thinking about trying a single patch-clamp experiment only to find the technique required a tremendous amount of skill, experience and patience (Lacking all this, I was extremely thankful for the expert help of a patch-clamp specialist in the department). So you can understand my amazement at seeing these robotic systems capable of doing it all now. And by all, I mean the whole process in a single box. These platforms obtain cells from either a culture flask or a holding tray (cells can be cultured for hours in the instruments prior to the experiment starting), centrifuge the cells to remove culture media prior to patching, place individual cells into wells for testing, form a seal to the cell surface (in most cases this is accomplished using a specific amount of suction which differs from cell to cell and has to be calculated for each patching experiment), add any compounds to be tested to the wells and finally record the conductance across the membrane in each well. All this in a basically unattended format.
Although these systems are expensive, it turns out that they are not much more than two or three complete traditional patch-clamping apparatuses without the cost of a couple electrophysiologists. All this got me to wondering as I rode the escalator out of the hall at the end of the day — is there a limit to what can be automated?