[Open_electroporator] culture shock tests on live cells

[Mitchell Altschuler]

Hey John,

Off to Chicago this morning so Ill have to wait to check on this either
late Sunday or Monday.
I still need to look through your emails in more detail from yesterday as
well.

However, it seems we were on the same page on how we  might be able to
detect that the device might work.
What you suggested was exactly what I was taking about and what I have.
Still i realize it may or may not work, but it it does something that a
good indicator.

In the meantime I have also been making an incubator and will get the stuff
I need to try Ecoli transformation.

Do you have a target organism  for this device?  Is it just Ec or are you
think animal, fungal and plant cells as well?

Yesterday I downloaded about 20 paper on EP.  Hopefully after reading that
I will have a better idea as to the science behind it.  In fact that is
where I found that low cost EP paper.  It was just an FYI. and there was
some references to other designs as well.  the other on related to insect
EP and as you said mostly localized to intact organisms.

best and thanks

Mitchell






On Thu, Jul 13, 2017 at 10:19 AM, John Griessen <john at cibolo.com> wrote:

> On 07/11/2017 12:25 PM, John Griessen wrote:
>
>> so you might try:
>>
>>> a(150, 4, 92)      # which is the default currently
>>> pulse()                # you'll see very fast pulsing, with very low HV
>>> ripple
>>> a(3194, 684, 6)  # set to replicate John's original settings
>>> pulse()                # you'll see the low and HV pulses like John's
>>> original settings
>>>
>>
> OK.  This above is the info we need in order to make a test suite.
>
> a(150, 4, 92) makes a voltage that tests the high range of voltage.
>
> Since your machine has a capacitor fallen off, (I apologize for my weak
> soldering with
> soldering iron instead of IR reflow), it won't go as high, but we don't
> know how much of
> a shortfall it will have -- it won't be a linear interpolation.  If we
> guess some numbers to go higher and
> if hits the limit of some of the component capacitors and diodes, the
> machine dies.
>
> So here is a set of parameters you could use on separate loadings of the
> cuvette to see if
> some survive better and if the volt threshold of poration is reached at
> all:
>
> Plug in the culture shock to USB, and see a prompt >
>
> > a(150, 4, 92)
> > pulse()
>
> reload cuvette, save and mark that cell suspension [a(150, 4, 92) 2mm gap]
>
> > a(150, 4, 65)
> > pulse()
>
> reload cuvette, save and mark that cell suspension [a(150, 4, 65) 2mm gap]
>
>
> > a(150, 4, 32)
> > pulse()
>
> reload cuvette, save and mark that cell suspension [a(150, 4, 32) 2mm gap]
>
> This last one has a slight risk of killing the machine, since it goes
> higher and the lack
> of one cap on the input side may not lower the energy transfer per
> switcher pulse very much...
>
> > a(150, 4, 102)
> > pulse()
>
> reload cuvette, save and mark that cell suspension [a(150, 4, 102) 2mm gap]
>
>
> Those values are likely to get some results on one of them if the machine
> still functions.
> You could also try much higher effective field strengths by using a 1mm
> cuvette
> instead of the 2mm cuvette I sent with the machine.  I recommend that
> instead of using the fourth
> set of parameters.
>
> There is no sanity check the machine is working since you have no test
> equipment to measure its output safely.
>
> You could send it back for me to rework if you like.
>
> Sorry I can't give you more certainty.  Thanks in advance for any testing
> work you do.
>
> --
> John Griessen
> cibolo.com  Austin TX  building lab gear for biologists
> _______________________________________________
> open_electroporator mailing list
> open_electroporator at cibolo.us
> https://cibolo.us/mailman/listinfo/open_electroporator
>



-- 
Mitchell Altschuler
925 212 2296
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://cibolo.us/pipermail/open_electroporator/attachments/20170714/7581de80/attachment.html>