I’ve been reading through numerous patents as concerns electroporation, for two purposes. First to create a low cost open source instrument for DIYbio and educational institutions, and secondly, to see what improvements could be made to the current art.
Electroporation otherwise known as transfection, is a method where a high voltage impulse is applied to a suspension of cells to introduce cloned DNA. I’m no biologist, but to me, its like using a garden hose to fill a reservoir the size of ones house, to feed a precision faucet which is connected to a series of tiny nozzle. The nozzles are located in a bathtub of colored oil and clear rubber balls located in a darkroom, where we can’t see a thing. The idea being if everything works right, when the precision faucet is turned on for just the right time period and flow velocity, it is possible to inject the colored oil into the rubber balls, with minimal destruction and maximum success of transferring colored oil to said clear rubber balls. Ie, some will explode, and others wont get any colored oil, and some will turn out the way we want. We wont know if it worked right, until we roll out the bathtub of oil and rubber balls into another room. We know we can vary the size of the reservoir, the restriction in the plumbing, the time duraction that the nozzle is open. We also can vary the turn on, steady state, and turn off rates. Ie. we can control the waveform somewhat, amplitude obvious, but also the waveshapr ranging from a square wave to an exponential impulse, and a range of values between the above.
COTS instruments have both square waves, and exponentially decaying waveforms. They also provide options for selection the amount of bulk charge which is stored, ranging from a sub microfared to in some cases, hundreds of microfarads. There are also provisions to apply wave shaping by the introduction of a range of resistance values. The impule itself may last for only a few usec, up to a few milliseconds. Lastly, the peak value of the waveform can range from a few hundred, to many thousands of volts.
The thing is this, 3KV stored in a 50uF capacitor is dangerous, its not unlike what defibrillators use to restart foks hearts. Current levels during the impulse are also very high, 125 Amps is needed for some procedures. We are n the domain of welding 1/4″ steel plate. Fortunately the time durations are very short.
As such, one can see why the commercial vendors of such equipment are few in number, apart from the market being small. The liability insurance, assuming one can even get a policy would be insane. Thus, the reason for not developing this as a product, but for going open source. One can also see why the prices are high. One has to cover the insurance costs, but also the volumes are low, the component costs can be high, and the basic science r-d can be time consuming and expensive. Of course open source doesn’t make all of this go away… its still there, and in some areas, quite a challenge.
This is especially the case in that high voltage design and fabrication is not for the novice. My co-workers years back used to joke about me and scorched labs… Few if any ever wanted to deal with high voltage, as its pretty crazy, and when things go wrong, they often do so in a huge way. Ie, you spend thousands of dollars on materials, and weeks of time to get a prototype, only to have it vaporized in a fraction of a second. Then you start over… Fortunately electroporation is a few steps below that level, but still, hazards are very real. I dont exactly know how to address that yet… just as I’m no biologist, biologists are not high voltage experts. I’m not one either, I’ve got thousands of hours working in the field, but no way would I consider myself an expert, there are just too many unknowns.
You might note, I dont use the term EE, as most uni programs do not go anywhere high voltage, and even those that do, often times focus on the utility side. Even then, the average undergrad, or even grad student is unlikely to have had much experience. They can analyze things to death, but simulations and high voltage as a general rule do not work out too well. Ie, its a rare model indeed that includes things like elevation above sea level, surface cleanliness, wire routing, or even thermal radiation effects which impact energy levels in glass devices… Its a different world.
Yet, I fully believe it is possible to make this a safe open source design. It may be the high voltage aspects end up under a do not mod under any circumstances unless you have blast shields, and other related precautions or other limitations. In addition there may be a way to provide for incremental test and verification, such that the chances for explosion on power up are minimized.
I also believe a design such as this needs to be open source. As in most cases, one either uses 3-5% of an instruments capability, and wishes for one minor feature, or one uses 100% of its capability, but if only there was a provision for one more thing, it would be perfect. Open source provides that option…
And of course, it also provides for rapid adoption of new technology… yep, already found a couple items which could be claimed if I were to do a patent application.