Non-Platinum Electrophoresis Electrodes That Don't Degrade

[Josiah Zayner]

I have been testing out a bunch of different metals and they either oxidize to death on the minutes timescale or in the case of stainless steel turn the buffer orange/brown.

Platinum wire is pretty expensive ~$1.00 cm^-1. Has anyone had luck with a cheaper metal at 100V or greater with TAE?

I have tried:

Nickel

Stainless Steel 430

Tinned Copper

Thinking of trying Titanium or Nickel Titanium (<= $4 meter^-1). Anyone ever tried these?

Thanks,

     Josiah Zayner

http://DoItOurselfScience.blogspot.com 

[Cathal Garvey (Android)]

I think the Pearl Gel Box used chrome-plated stainless steel? Graphite is another popular option.

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[Avery louie]

I did some testing with super-elastic (non-kink) nitanol (not SMA) and it survived, but it was pretty light testing.

I have also tested gold-plated (ENIG) PCBs, but those get eaten pretty fast.

--A

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[Josiah Zayner]

I can't really find much on chrome plated wire online or a place that sells it. Any ideas?

Graphite rods look like an ok solution but seem complicated to attach and use without breakdown of other metals.

[Jonathan Cline]

Random idea: perhaps you can attach the wire end in solution to another piece of metal, which will act as a sacrificial anode, thus saving the wire itself.  Then only the sacrificial piece (presumably, cheaper metal) needs to be replaced.  For example, a big chunk of zinc.  Main reason this comes to mind is that I've got a nice chunk of zinc on the outside of my sailboat which sits in salt water (akin to a buffer), exactly for this purpose: the zinc oxidizes instead of the other brass/bronze on my boat similarly exposed to the buffer; this is a problem on boats due to stray currents in the electrical system (basically, making a battery, electron migration).  This idea may not work at all, never seen a reference to it in a publication on electrophoresis.  Magnesium is used as a sacrificial anode but only in fresh water.  Aluminum is an alternative in salt water.


Hmm, here's a patent which suggests using carbon nanotubes.  Apparently nanotubes are the answer to everything right?

  Ref: http://www.google.com/patents/US8329004

On Sunday, May 26, 2013 8:34:11 PM UTC-7, Josiah Zayner wrote:

I can't really find much on chrome plated wire online or a place that sells it. Any ideas?

Graphite rods look like an ok solution but seem complicated to attach and use without breakdown of other metals.
 

 

## Jonathan Cline
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[Dakota Hamill]

Isn't just spending the money on platinum worth not having to deal with trying to find other solutions?   

It might sound  unscientific to say that but, if you factor in the $$$ and time spent on trying to find another solution, which I'm sure others have as well, wouldn't it be just as, if not more cost effective to go with platinum wire?

[Patrik D'haeseleer]

I would not call one dollar per cm "pretty expensive". That's what, $20-40 per gel box? How does that compare to the power supply you're using to run the electrophoresis?

I've used stainless steel wire without much noticeable corrosion during a single run. But yeah, I would expect you'll need to replace the wire every couple of gels at least. If your gel box is designed such that it only takes a few minutes to swap out fresh stainless steel wires for every gel, that could defintely be an option.

Anyone see any side effects you might get from having some additional iron or chromium ions in the buffer, from corroding stainless steel electrodes?

Patrik

[Cory Tobin]

I have a couple gel boxes made with nichrome wire. They're not
perfect. After about 3 months of daily use they start to look
corroded but considering it's easy to work with and is super cheap
(around 10 dollars for 100 feet of 26 gauge wire) I think it's a good
option to consider.

-cory

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[Pieter]

I used gold wire, because it was cheaper than platinum at the time. Make sure you get pure gold though... at first I used 14 carat, but that corroded super fast

[Conner Berthold]

I had an idea a few days ago about using platinum spark plugs as the electrodes. One could be placed at each end and the center used for the electrical in/outputs. I hope to be building a few boxes soon and would just thread holes for them. Another plus would be that they could be changed out easy if they ever corroded.

Any ideas?

-Conner

[Nathan McCorkle]

A point electrical source might drag all the DNA to the center of the gel

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[Roger Stager]

I have had good luck with stainless steel seizing wire from West Marine. It is $20 for 55 ft.  I often run 150v with TAE and no corrosion of the wire or discoloration of the buffer. 

Roger 

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[Josiah Zayner]

Thanks for the info Roger. I will buy some and check it out. Exactly what I was wondering.

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[Roger Stager]

Josiah,

If you have any problem getting the wire let me know.  I have extra and would be happy to send you a piece. 

Good luck

Roger

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[John Griessen]

On 05/26/2013 10:34 PM, Josiah Zayner wrote:
> Graphite rods look like an ok solution but seem complicated
> to attach and use

How about O-ring seals in a gel box wall. Then connectors and metals
are all outside the box. Perhaps a water tight cord grip for electric power cords
would be an expedient DIY method of constructing such a gel box feed through for
a graphite rod. The other end of the rod could go to a hole that only goes half
way through the gel box to support the rod end so it's not along lever
that could let it get broken easily. For an open hardware product, a simple
turned shape attached by screws could clamp against an O-ring in its
groove to seal the rod.

On 05/26/2013 11:44 PM, Dakota Hamill wrote:wouldn't it be just as, if

> not more cost effective to go with
> platinum wire?
>

Sure, but it only benefits one at a time DIY expedience. More effort is worth
it if you can develop open hardware to share, especially if it results
in ease of use, long useful life, cleanable, rebuildable, etc.

For circuit printing, there are carbon inks that cure with heat.
What if one wall of a gel box was printed with in a big rectangle
of conductive carbon "ink" that goes above the gel height?
Wonder if it would last like pure carbon rods?

[Nathan McCorkle]

The graphite rod with a compressed o-ring is a good idea I think.
We're planning to build gel boxes here in Portland soon, I'm scraping
together ideas for what to try out now. Vacuum forming came to my
mind, but if the plastic is so flimsy how would you compress the
o-ring? I'm thinking of trying HDPE from Gallon sized milk jugs, and a
youtube video recommended polystyrene disposable kitchen/picnic
plates.

But where to get cheap graphite rods? Amazon.com sellers want around
$1/inch... seems a pencil is about 20-30X cheaper. Maybe firing
pencils would allow extraction, or is pencil graphite not actually
lead (like how they're called lead pencils)?

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-Nathan

[Simon Quellen Field]

Mechanical pencil leads are readily available.

Like normal pencil leads, they are graphite with a clay binder.

You can check the conductance with an ohm meter.

Instead of the O-ring, you might try a dab of rubber cement.

I had good luck using copper tape to make the connections.

It is sold in hardware stores -- copper foil with a sticky backing.

They advertise it as a snail barrier.

Similar tape is used for alarms on windows.

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[John Griessen]

On 06/03/2013 06:17 PM, Nathan McCorkle wrote:
> Vacuum forming came to my
> mind, but if the plastic is so flimsy how would you compress the
> o-ring? I'm thinking of trying HDPE from Gallon sized milk jugs,

Been busy...

I think HDPE would be a great low cost material for a gel box.

How about roto molding it thick instead of vac forming? For roto molding,
you get the plastic hot and runny, and the mold might need to be not too cold
that freezing happens on contact, then you rotate to get an even film
while cooling down, then open the mold.

I have not done this. It's a known technique though.

Probably better would be a 3DP that uses plastic granules instead of filament
and uses HDPE to get a near net shape, then mill it. You get to recycle the
milling chips.

OK, back to your reality of DIYness... get a cord clamp.
It will tighten onto a thin wall like a milk jug, and
seal a feed-through ( the graphite), also.

John

[Nathan McCorkle]

I did this a few days ago, sorry it took me so long to grab the pics
from devices.

I added about a teaspoon of table salt to around 300mL of tap water,
and electrolysed for probably an hour on an average of probably 6
volts or so, using mechanical pencil leads. One section of the
positive lead swelled and snapped the end of that electrode off
(splintered, not a clean snap). I'm guessing there was a bit of stress
from dangling the wire into the jar and the electrode was pressing on
the wall of the jar a bit. I don't think that would cause the swelling
though. For kicks I tried grabbing the unbroken electrode, and
grabbing it at points >1 inch apart I bent the rod, it sheared in a
clean fashion, no splintering.

http://diyhpl.us/~nmz787/pics/graphite_electrodes_fail/

For $1/cm, I'm starting to think $10 or so for a gel box isn't too
bad. It's certainly not give-away-for-free though. Maybe NaCl simply
isn't a good test substitute for electrophoresis buffers (chlorine and
NaOH production, in the buffer the NaOH would be dealt with at least).

I'll have to try this again with different buffer.

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[Eugen Leitl]

On Thu, Jun 06, 2013 at 01:58:36PM -0700, Nathan McCorkle wrote:
> I did this a few days ago, sorry it took me so long to grab the pics
> from devices.
>
> I added about a teaspoon of table salt to around 300mL of tap water,
> and electrolysed for probably an hour on an average of probably 6
> volts or so, using mechanical pencil leads. One section of the

There are better graphite electrodes available in your average
alcaline battery.

[Avery louie]

conductivity, unless it is really really low, is not going to be an issue compared to the resistance of the gel/buffer.

316 stainless wire works pretty well.  it is a stainless steel.

--A

On Sat, May 3, 2014 at 12:31 AM, Yuri Steinberg <ybrau...@googlemail.com> wrote:

Is there anywhere I can find data that compares prices, conductivity etc of different metals as electrodes for electrophoresis ?

On Sunday, May 26, 2013 2:29:19 PM UTC-4, Josiah Zayner wrote:

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[Nathan McCorkle]

You can even use nonmetals such as graphite.

On May 5, 2014 5:00 PM, "Yuri Steinberg" <ybrau...@googlemail.com> wrote:

Is there anywhere I can find data that compares prices, conductivity etc of different metals as electrodes for electrophoresis ?

On Sunday, May 26, 2013 2:29:19 PM UTC-4, Josiah Zayner wrote:

[Patrik D'haeseleer]

On Monday, May 5, 2014 5:02:44 PM UTC-7, Avery wrote:

conductivity, unless it is really really low, is not going to be an issue compared to the resistance of the gel/buffer.

316 stainless wire works pretty well.  it is a stainless steel.

Ditto on using stainless steel. Graphite electrodes from batteries sound great in theory, but they come in a limited range of easily sourced sizes, you'll still need to connect a wire to them, and I would worry about any chemicals absorbed or mixed into the graphite. 

In contrast, stainless steel wire can be bought by the yard, costs just pennies per electrode, and can be shaped however you like it. 

Patrik

[Nathan McCorkle]

Mechanical Pencil graphite works, I imagine sharpened pencil would work for a single lane/well.

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[John Griessen]

On 05/07/2014 05:06 PM, Patrik D'haeseleer wrote:
> On Monday, May 5, 2014 5:02:44 PM UTC-7, Avery wrote:
>
> conductivity, unless it is really really low, is not going to be an issue compared to the resistance of the gel/buffer.
>
> 316 stainless wire works pretty well. it is a stainless steel.
>
>
> Ditto on using stainless steel.

Has anyone tried Monel alloys?

They are >63% nickel and copper and other for the remainder.
They ignore sea water weather corrosion, so maybe are good for electrodes. One use has
been on aircraft for keeper wire that stops nuts coming off from vibration, so it is
available as wire as a standard sort of low cost product. Stainless steels are
mostly >75% iron, so they are lower cost, but -- when comparing to platinum...not much
difference.

[PoeVA]

Interesting idea Conner!  I had no idea spark plugs had Pt.  Also, good point Nathan about the point source causing problematic distortion in a 2D gel.  I wonder if a decent electrical field could be created with an evenly spaced array of spark plugs (or small lengths of Pt wire).  Somebody fire up some E field modeling* :)

-Brian

* COMSOL or ANSYS might be fairly turnkey... or, for the brave, Mathematica/Matlab/NumPy should do it.  I haven't even Googled it (let alone Google Scholar), so forgive me if prior work on the electrode array front is laying in plain sight.

[PoeVA]

Stainless is an attractive option, but be advised that it may give off [very] toxic chromate as the SS is electrochemically degrading.  Using SS for the anode could produce toxic (illegal to dump) chromate*.  I noticed a stern warning in an instructable I read a while ago about electrorefining or electrolyzing rust; it said to avoid stainless.  Both of those examples are from much larger amounts of metal electrolyzed over longer times, but even if you can't see the chromate, it will be there if your SS anode degrades.  It might seem fine (and low levels of chromate aren't optically visible), but I'm concerned that with long run times and buffer reuse it could accumulate; then if you have chronic exposure (ever had to run gel after gel after gel after...?  yeah.)  Last point, you don't want to be illegal or raise the hackles of the EPA and other regulatory agencies.

Best wishes,

Brian

* (as describe here).  

**(sorry, couldn't find it again before posting this, but I didn't have much time to look)

[Narasimmhan Thulasisha]

Dear sir,

  thks for your replay

Regards,

T.Narasimmhan

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[Jonathan Cline]

Presumably with placing two conductors at each end of the tray, switching these alternatively on/off would average out the movement of particle through the gel and also perhaps speed the separation in the gel run since the movement is a zig-zag through the matrix.  

try reading some actual journals some time, like Electrophoresis, which has plenty of validated, published research articles on this subject around 1980 +/- 10 years. 

You know, actually RTFM!!

 

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On 10/19/15 10:28 PM, PoeVA wrote:

[Markos]

Hi,

Just my two cents.

Have you considered to use the filament of electrical resistance of shower?

And the carbon brush used in electrical motors?

Or graphite of pencil?

Best Regards,
Markos

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[Bryan Jones]

Carbon electrodes is a good idea. Another good source of carbon rods is from lantern batteries (heavy duty, not alkaline). http://theodoregray.com/periodictable/Stories/006.2/index.html

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[John Griessen]

I had an urge to search for a while, and found some practical info about electrodes that could help.

1. The bigger they are -- http://www.sciencemadness.org/talk/viewthread.php?tid=1519
Has amateur chemists talking about
driving reactions with electricity and high voltage. They say that current density is what causes graphite to
decay, not how high the voltage is.

So, with big area of an electrode as a guide, ebay China sellers offer fat electrodes 150mm long for $1.25 --
http://www.ebay.com/itm/5-pcs-99-99-Graphite-Electrode-Cylinder-Rod-Length-150mm-Diameter-5mm-U6C-7-/181566352494

2. The harder they come -- http://link.springer.com/article/10.1007%2Fs10800-008-9518-2?LI=true paywalled paper
A guide just from the abstract:
"This work studied the voltammetric response of graphite reinforcement electrodes made of different pencil
lead hardness. The studies showed that harder graphite leads, regardless of their manufacturer, are more
appropriate as electrode material for voltammetric purposes due to their higher peak currents,
increasing sensitivity and reproducibility"

So, hard drafting pencil leads might be good for electrophoresis:
9H is super hard, and available from aliexpress --
http://www.aliexpress.com/item/KOH-I-NOOR-2-0-mm-Mechanical-Lead-Graphite-Lead-Black-9H-7H-6H-5H-4H/32393524530.html
$6 for 12 pieces 120mm long

3. Pt alternatives -- Not a low cost answer, but on http://www.sciencemadness.org/talk --
Someone mentioned iridium as electrode lasts for decades in production use and costs same as Pt.

4. Nano surfaced pencil graphite --
http://www.linknovate.com/publication/mwcnt-modified-composite-pencil-graphite-electrodes-fabricated-by-direct-dripping-and-electrophoretic-deposition-methods-a-comparison-study-1480071/
This article is available free for this week because the publisher is letting down their paywall
as a promotion. You can wade through how to get it, or ask me to resend it. has nice SEM photos
of 6H (hard) pencil lead and 2B (soft) before and after coating with CNTs.

[CindyB]

I've been working on this problem, too. I'm trying the graphite approach. Electro-discharge machining (EDM) is the source I've been exploring for graphite. It's very cheap. There are grades with no fillers added. 100% carbon. The big problem is sealing the liquid in at the box connector point. Here are a few of the sources I've used:

http://www.graphitestore.com/index.asp

The main problem with graphite seems to be electrolysis creating gas bubbles that break apart the layers creating a film of carbon bits in the buffer and clogging up the gel. Here is a decent paper on the mechanics of electrolysis in the graphite:
http://www.scielo.br/scielo.php?pid=S1516-14392014000100012&script=sci_abstract
Since I'd like to minimize electrolysis, this paper gives some clues for experimental design.

Here is a discussion thread on connecting copper connector to a graphite rod.
http://cr4.globalspec.com/thread/12335/How-to-connect-copper-wire-into-carbon-block

Here is a table of material parameters of different EDM graphite grades:
http://dev.mkprogramming.com/mwi/wp-content/uploads/2014/10/EDM_ECGrades.pdf

I tried taking the Pt electrode out of the conventional BRL gel box to use as a pattern to cut an L-shaped graphite electrode out of the softer graphite. It's just a few nut thread turns too thick to place the cut-out graphite back in the electrode position in the box. I'd love to find the screw/nut connector with about another 3-4mm more of thread. I think I could get a seal with that.

I'm still working on my electrophoresis system but, with the graphite electrodes, the cost of the electrodes is not my foremost problem anymore.

Cindy

[John Griessen]

On 10/23/2015 08:29 AM, CindyB wrote:
> I tried taking the Pt electrode out of the conventional BRL gel box to use as a pattern to cut an L-shaped graphite electrode out
> of the softer graphite. It's just a few nut thread turns too thick to place the cut-out graphite back in the electrode position in
> the box. I'd love to find the screw/nut connector with about another 3-4mm more of thread. I think I could get a seal with that.

Try looking at electrical cord grips. They are used for industrial wiring of stranded wire cables to a knockout hole in an
electrical box.
Some are made with an O-ring so they seal to the electrical box. The grommet that seals against the "cord" allows for diameters
from 3mm to 11mm usually -- just by hand tightening a molded plastic cap

[Abizar Lakdawalla]

An FYI - ions generated from stainless steel, zinc metals, chromium, lead, copper, etc. during electrophoresis degrade RNA and DNA by attacking the phospohodiester backbone. If you are planning on cutting out DNA bands from your gel for cloning or other work - only platinum, gold or graphite electrodes would work. 

Conductive plastic?

[Leonid Benkevitch]

I believe silver can be a good candidate. Although I read that only 0.99999 (5 9s) purity can be used, I am going to try the Canadian silver coins of 0.9999 purity. 

Silver ions are considered benign to the human body, aren't they? 

Silver is relatively expensive, but it is quite affordable for medical use. I used to buy the silver coins from the quite reliable web store http://www.jmbullion.com/

Look at the prices and sizes there:

1 oz (31.1g), 0.9999, 38mm x 3.29mm,  5-dollar Canadian Maple coin: $20.23;

1/2 (15.55g), 0.999, 32.5mm x 2.06mm, Sunshine Silver Round: $10.01

1/4 oz (7.77g), 0.999, 20mm x 2mm,  HM Morgan Silver Round round: $5.80;

As we can see, only 1oz Canadian Maple Leaf is 0.9999 pure. Also, you can buy a little of silver wire on ebay to weld it to the coin/bar electrode.

[suresh kumar]

    
   How to convert chemical energy higher than 40kJ to electrical energy? What are the best and cheap electrodes? could you help me with that?

[Cory J. Geesaman]

You might try either Platinum-coated copper electrodes or straight Carbon electrodes - both Platinum and Carbon should be inert when it comes to electrolysis (effectively what you're doing with electrophoresis.)

[Cory J. Geesaman]

When you say Portland, you don't mean Maine do you?  I've been trying to get a DIYBio group going here for awhile.

[Cory J. Geesaman]

This could actually work really well even with the resistance of the graphite in pencil lead: take a copper wire and bond it with conductive epoxy to a very straight line along the lead (to reduce the surface area as much as possible) then coat that side with an insulating epoxy so only the lead is exposed.  If you use something like magnet wire you could just leave the enamel on where the wire comes out of the epoxy-coated portion of the graphite, then dunk both tips of the graphite in an insulating epoxy for good measure.  At that point when you're talking about electrophoresis voltages the resistance of  the graphite should become trivial and the copper will ensure an even spread of voltage.

[Leonid Benkevitch]

> But where to get cheap graphite rods?

You can get plenty of grafite rods from old batteries -- any AA, AAA and others contain a carbon rod inside.

2017-09-18 23:31 GMT-04:00 suresh kumar <mksures...@gmail.com>:

    
   How to convert chemical energy higher than 40kJ to electrical energy? What are the best and cheap electrodes? could you help me with that?

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[Nathan McCorkle]

On Tue, Sep 19, 2017 at 11:44 AM, Cory J. Geesaman <co...@geesaman.com> wrote:
> When you say Portland, you don't mean Maine do you? I've been trying to get
> a DIYBio group going here for awhile.

Nope, Oregon.

[Björn Johansson]

Hi all and sorry for resurrecting this old thread.

I have retrofitted some old electrophoresis units with stainless steel wire for electrodes and this works using TAE buffer for a while before the 

buffer gets an odd color (green).

However, I recently cam across a superior buffer containing LiAc and boric acid and this seems much more aggressive, the unit fills up with rust after one run.

Platinum wire is an obvious choice, but it is quite expensive. 

I came across something I think wasn't mentioned here: conductive brush wire (sold here).

This wire is probably used for brushes that can not be allowed to build up static electricity.

This wire seems to be made from some plastic with a carbon filler.

Could this be an option?

/bjorn

[Bryan Jones]

Interesting find. Conductive polymers might be an option. However, the threshold for conductivity to be a good wire is much higher than to dissipate static. If I understand the units correctly (I don't quite get sheet resistance, especially since these are not sheets but bristles), I think these brushes have a conductivity somewhere between that of wood and glass. That is conductive enough to not build up static, but still more of an insulator than a conductor. Are there more conductive polymers out there? I think you'd want something sub-ohm, while these are 10,000-1,000,000 ohms/square. What about something like this: https://www.alibaba.com/product-detail/graphite-polymer-super-thin-high-thermal_60530140212.html?spm=a2700.7724838.2017115.1.22c14c640y8th5&s=p?

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[Abizar Lakdawalla]

I used mixed wires, Platinum for one and nichrome (from an old toaster) for the other electrode. So I guess halves the cost. Pt wire can be bought from Jewelry supply houses.

Link to the youtube video describing the construction

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[Nathan McCorkle]

On Tue, May 22, 2018 at 11:24 PM, Björn Johansson <bjor...@gmail.com> wrote:

Hi all and sorry for resurrecting this old thread.

Please don't be sorry... it's not like old things are bad... and keeping related conversation organized is helpful for searching later. 

[Bio Logis]

Hi Abizar,

do you think that 96,0 platinum wire would be ok, or would you recommend 99,9% Platinum?

Do you think that 0,075mm platinum wire would work as well?

Thank you by the way for the tip about NiCr-Electrodes, they seem to work ok.

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[John Griessen]

On 05/24/2018 11:05 AM, Bio Logis wrote:

> On Wed, May 23, 2018 at 9:05 AM, Bryan Jones <bryan...@gmail.com <javascript:>> wrote:
>
> Interesting find. Conductive polymers might be an option. However, the threshold for conductivity to be a good wire is much
> higher than to dissipate static.

There are conductive carbon based inks for making circuit traces that survive normal circuit processing which includes
washing. They might be water proof enough to last some number of cycles of gel electrophoresis... and not release metal ions...

[Jonathan Meuser]

My first time posting, so apologies if this was already covered. Would glassy carbon work as an electrode material?

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[Björn Johansson]

This seems to be a common application for glassy carbon https://en.wikipedia.org/wiki/Glassy_carbon

What about black teflon or nylon with carbon powder? Anyone tried this?

[A No Body]

This may be a shot in the dark but has anyone tried organic wires?

[A some body again]

it may take longer to electrophorese but the effect should still be the same. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3929695/

[Abizar Lakdawalla]

Have used heater wire from an old toaster (think it might be nichrome) for the negative electrode without any issues ... Used a very thin Platinum for the positive though.

https://www.youtube.com/watch?v=SPqADxHMY-I

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[Jeff Backstrom]

Never tried it, but since silver and palladium are both noble metals, maybe palladium silver wire (3% Pd, 92.5% Ag) would work. Or perhaps palladium by itself; a quick perusal of prices on eBay show it might be viable.

The other oddball that isn't a noble metal that comes to mind is niobium. Surprisingly inexpensive for such a remarkable metal.

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[John Griessen]

On 10/7/18 4:26 PM, A some body again wrote:
> it may take longer to electrophorese but the effect should still be the same. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3929695/
>
> On Sunday, May 26, 2013 at 2:29:19 PM UTC-4, Josiah Zayner wrote:
>
> I have been testing out a bunch of different metals and they either oxidize to death on the minutes timescale or in the case
> of stainless steel turn the buffer orange/brown.

I gave this a partial read and its very promising sounding. It may take 5 times less time, not more time...

and it seems open enough to make an OSHW product from, if paying royalties on the special electrodes is not too costly:


-- Conducting Polymer Electrodes for Gel Electrophoresis --
Katarina Bengtsson, Sara Nilsson, and Nathaniel D. Robinson *
Alexei Gruverman, Editor
Transport and Separations Group, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden,
University of Nebraska-Lincoln, United States of America,
* E-mail: es.uil.mfi@ortan
Competing Interests: The authors have read the journal’s policy and have the following conflicts: author Nathaniel D. Robinson
owns a part of a company (Lunavation AB) that owns a daughter company (LunaMicro AB), which holds the following patent and pending
applications for the use of pi-conjugated polymer electrodes for microfluidic and electrophoretic applications: Swedish patent
SE534488 (Ett system för elektrokinetisk flödesteknik), and patent applications WO2011102801, EP2011744981, JP2012553852, and
US13580343 (An electrokinetic fluidic system). There are no further patents, products in development or marketed products to
declare. This does not alter the authors’ adherence to all the PLOS ONE policies on sharing data and materials.

Conceived and designed the experiments: KB SN NDR. Performed the experiments: KB SN NDR. Analyzed the data: KB SN NDR. Contributed
reagents/materials/analysis tools: KB SN NDR. Wrote the paper: KB SN NDR

-- Conducting Polymer Electrodes for Gel Electrophoresis --

The results of big chemical and color changes in gels would be long gone....

[zahra fayazi]

I used platinum as a electrode for electrophoresis but I foound a black sediment on positive one after using .does any one k

now the reason?

On Sunday, May 26, 2013 at 10:59:19 PM UTC+4:30, Josiah Zayner wrote:

I have been testing out a bunch of different metals and they either oxidize to death on the minutes timescale or in the case of stainless steel turn the buffer orange/brown.