Practical applications of Electrophoresis? - Page 1
Forum section: electronics / general

author: XOIIO
author_rank: Super Contributor
timestamp: July 03, 2014, 05:56:56 pm
content: Hey all, I ordered a for part/not working Gibco BRL Electrophoresis Power Supply, listing said it had no fuse to test so I am hoping it will just need one, cost me $49 which is pretty good. From what I can find it's a variable power supply, 0-250v with 500ma current, and I am not sure but I believe the current is adjustable too.I found the Wikipedia article on Electrophoresis, but I am trying to think of a practical or in home use for it, aside from a nice high voltage power supply which I have wanted for a long time. It doesn't go up to 400v, but 250 ain't bad.

author: kolonelkadat
author_rank: Regular Contributor
timestamp: July 03, 2014, 08:22:43 pm
content: you could use it to isolate dna for genetic experiments, if youre into that sort of thing.

author: PedroDaGr8
author_rank: Super Contributor
timestamp: July 03, 2014, 08:45:51 pm
content: Quote from: XOIIO on July 03, 2014, 05:56:56 pmElectrochemistry, electroplating, etc.

author: pickle9000
author_rank: Super Contributor
timestamp: July 03, 2014, 09:17:46 pm
content: Probably has a safety. No output unless connected to device.

author: dannyf
author_rank: Super Contributor
timestamp: July 03, 2014, 09:22:36 pm
content: QuoteImpress your neighbors?Zap some mosquitoes?Explore the universe?Expand your knowledge base?Publish a paper in Nature?Get you tenured at a reputable university?Get research grants from NFS?...The list is limitless.

author: mariush
author_rank: Super Contributor
timestamp: July 03, 2014, 09:31:29 pm
content: If you have money to waste, I guess it's a good buy.You should have searched for the manual or some documentation before buying, especially if you don't even know what electrophoresis means.My guess the current varies with the selected voltage, meaning you can probably get 500mA at 0-10v or something like that, but you can probably only get 2-5mA at 250v.. so not as much use as you'd think.

author: HighVoltage
author_rank: Super Contributor
timestamp: July 03, 2014, 09:44:55 pm
content: I have one for a long time and I use it to load up high voltage circuits, to see how stable they are and what the current flow is under high voltage DC conditions. It works extremely well for this.Just be extremely careful, if you do not know what you are doing.

author: XOIIO
author_rank: Super Contributor
timestamp: July 04, 2014, 12:24:24 am
content: Quote from: pickle9000 on July 03, 2014, 09:17:46 pmIt's just got four terminal output, I'm thinking it maybe has voltage sense.Quote from: mariush on July 03, 2014, 09:31:29 pmGST check came in, so I figured "hey free money!". Got this, and a CVD 700 model 6B coming, as well as a raid battery for my server if that is what is indeed wrong with it, it stopped booting today :/I guess I will see what the current is at higher voltage, I did have small scale electroplating in mind as a possibility.Quote from: kolonelkadat on July 03, 2014, 08:22:43 pmHmm, how hard can that be? lol

author: AlfBaz
author_rank: Super Contributor
timestamp: July 04, 2014, 01:31:24 am
content: Quote from: XOIIO on July 04, 2014, 12:24:24 amDon't you just hack into a glass and add dishwashing liquid

author: XOIIO
author_rank: Super Contributor
timestamp: July 04, 2014, 03:08:24 am
content: Quote from: AlfBaz on July 04, 2014, 01:31:24 amApparently they use gel, so I think maybe save up some spit, and make jello with it (not all spit but maybe a quarter of a cup), I don't think flavor matters, then just hook up the 250v and watch the DNA come to the surface.

author: Unknown
author_rank: Unknown
timestamp: July 04, 2014, 04:05:04 am
content: Quote from: XOIIO on July 03, 2014, 05:56:56 pmFunny thing is it used to be common to see old "B battery" eliminators - a transformer, rectifier, voltmeter, ammeter, and a rheostat - used as electrophoresis supplies, since the real deal from a lab equipment supplier was ridiculously expensive. Something like that is enough to run a few small lanes.I know a few old profs who still swear by them, & keep the same setup in their private labs for things like quick-and-dirty specimen ID.

author: calexanian
author_rank: Super Contributor
timestamp: July 04, 2014, 04:57:27 am
content: Sylvania used cataphorisis (Just another name) for coating cathode selves with carbonate emission material in electron tubes. I believe they still use it for coating florescent light filaments.

author: saturation
author_rank: Super Contributor
timestamp: July 11, 2014, 12:21:39 pm
content: I can't think of something practical for you to do, other than experiment with it so you can see what it does. All these power supplies are are low quality [ aka noisy, or limited stability] DC power supplies with high voltage or high power.To do electrophoresis, the minimum you need is clear jello or something like it. Place the electrodes on opposite ends of the jello with a suitable plate as long as the length of the jello at the end. place a drop of your test substance on one end, then electrify the jello.The molecules of the test item will migrate across the gel pulled by EMF so you can separate them and extract it but slicing off the jello with the desired molecules in it. But the practical aspect of it is you may need a dye to see the molecules [fountain pen ink or iodine can work for some items], the voltage to cause the migration varies from one type of protein to another to tweak it enough to split it apart, and the gel material must be evenly distributed or a fixed matrix size so the migration is even. If there are impurities in the gel it will migrate too. These are critical items that affect the yield of your process.Importantly, most items used except wires and electrodes on the PSU use plastic, glass or similar, because the setup is a shock hazard, if not for the kV there are fluids all over the place. Once the phoresis is on, the setup should be in a clear shielded box so you can't get to any conductive parts of it, but you can see if should it go awry, .e.g. cook the gel due to excessive power.

author: Unknown
author_rank: Unknown
timestamp: July 11, 2014, 02:15:29 pm
content: Quote from: saturation on July 11, 2014, 12:21:39 pmThey're not particularly accurate, but HV DC supplies rarely are. All they've got to do is supply up to a couple of hundred mA at the dialled-up voltage without drooping too much. They're reasonably quiet though, since too much ripple or noise stuffs up the definition.Quote from: saturation on July 11, 2014, 12:21:39 pmAgar - or, more specifically, purified agarose of a selected polymer size. Gelatine doesn't work (I had several 10's of kg of gelatine powder left over finishing my postgrad thesis; that was one of the many things I tried for fun & giggles*), probably due to (at a guess) too many random-length polymers - it just sort of separates into a gluggy mess at one end and a runny mess at the other. Jello almost certainly won't work either, since it's basically gelatine + sugars + flavours + colours.Quote from: saturation on July 11, 2014, 12:21:39 pmThe voltage doesn't 'split' the proteins (generally, you dont want to split the proteins anyway) - it just affects the rate & distance they migrate. You separate the proteins of interest from the other crud beforehand (typically macerate/crush -> solvent to extract) & stain them, then you use electrophoresis to rank those proteins by size - splitting them simply results in a bunch of smaller & very similar-sized protein fragments migrating further together, making separating & IDing them hard.Quote from: saturation on July 11, 2014, 12:21:39 pmNo KV involved at all - the rule of thumb is something like 5v/cm of lane length IIRC. Most electrophoresis supplies only go up to ~250V or so, and a 15cm lane only needs ~80v to work. Too high a voltage, and you just end up dragging everything of interest right up to one end too quickly.(* I also learned you can't make agelatinous cubeof any appreciable size - ~1' sq is about the limit for typical industrial gelatine; above that you rapidly run into diminishing returns thanks to the cube-square law...)<- not real!

author: saturation
author_rank: Super Contributor
timestamp: July 11, 2014, 08:18:01 pm
content: Thanks Tac, your methods and explanations are better. But you can still do it on the cheapo side [and less clean results too], thus the jello, but in the Pacific our jello deserts use agar agar as a base which gives better results to gelatin jello. There are several low cost DIY on the web that can be tried.http://openwetware.org/wiki/IGEM_Outreach:_DIY_Gel_Electrophoresis,_Doing_Science_With_Household_Materialshttp://danielpacker.org/open-source-pcr-and-electrophoresis-roundup/Yes, as you suggest the voltage used depends on what you need done, see this as example and the root. When I was in school we used as high as 1kV, the new studs have methods using 3kV and up.http://pingu.salk.edu/~sefton/Hyper_protocols/Electrophoretic.html

author: Unknown
author_rank: Unknown
timestamp: July 12, 2014, 02:37:41 am
content: Quote from: saturation on July 11, 2014, 08:18:01 pm(Sorry if I was a bit OTT earlier - it was late night/early morning for me)Interesting. I know plain grocery-store agar can work for simple things even if it's not optimal. I didn't realise agar-based jello deserts were common - they exist here, but they're mostly restricted to the 'vegetarian' shelves of shops. Agar has a few properties that make it less easy to use than gelatine for jello (aka 'jelly' in my part of the world) - sugars particularly muck with the 'set' much more than they do with gelatine.Quote from: saturation on July 11, 2014, 08:18:01 pmDepends what you're doing - gel electrophoresis doesn't use kV voltages, but capillary electrophoresis (a slightly different technique for slightly different purposes) does. I should probably have acknowledged the difference...

author: Smokey
author_rank: Super Contributor
timestamp: July 12, 2014, 05:23:57 am
content: This sounds familiarhttps://www.eevblog.com/forum/testgear/what-to-do-with-new-toy-6000v-power-supply!!::EDIT:: Stupid links

author: miguelvp
author_rank: Super Contributor
timestamp: July 12, 2014, 10:16:13 am
content: https://www.eevblog.com/forum/testgear/what-to-do-with-new-toy-6000v-power-supply!Fixed the link for you

author: XOIIO
author_rank: Super Contributor
timestamp: July 12, 2014, 12:11:04 pm
content: Man, 6000v psu, that would be awesome to have, plus that one is programmable too.

author: mrflibble
author_rank: Super Contributor
timestamp: July 12, 2014, 07:23:35 pm
content: Quote from: saturation on July 11, 2014, 08:18:01 pmWoah.Electrophoresis with 1kV? I was aware of electroporation at a few kV to sneak plasmids past membranes, but that's a wee bit different than running a gel. Is this with a real dense polymer mesh or something?

author: saturation
author_rank: Super Contributor
timestamp: July 13, 2014, 12:20:49 pm
content: Yes, some methods use kV easily. See the link to what I use those PSU for in a non-biologic setting. I think I got my 3kV EC Apparat model for $10-20 plus $20 to deliver.How to choose among different types of PSU, from Bio-Rad:http://www.bio-rad.com/en-us/product/powerpac-hv-high-voltage-power-supply?pcp_loc=catprod

author: XOIIO
author_rank: Super Contributor
timestamp: July 15, 2014, 10:01:05 pm
content: Well, it came in today, however they tried to deliver it at my mothers house, and being the kind generous soul she is, she sent it back because they wanted $!6 COD, so thanks to her selfishness/laziness, I not only have to wait till tomorrow, but drive almost all the way across town probably spending another $16 in gas.I hate my family sometimes.edit: well, not the PSU, which sucks, still, a 35 minute drive both ways to pick this thing up.Sigh