7 replies to this topic

[Trinity]

I tried to cast SDS Page gels, but the mix of alle the components didn´t polymerized??? Why it it still liquid?
Do all the components do need to be very fresh? (Acrylamide, TEMED, APS) Which one is the most sensitive?

Edited by Trinity, 21 January 2005 - 06:16 AM.

[Trinity]

Anybody help me?

[jadefalcon]

Hey, come on , a little patience, ok?  

most likely you will get a answer here, but after just one hour an answer is quite unlikely...

ok, most of the time when SDS-PA gels will not polymerise it's the fault of APS. this should be relatively fresh, and loses activity after prolonged periods of storage- we aliquot freshly prepared APS-solution and store the aliquots at -20°C. Once thawed, an aliquot is used for about 3 to 5 days and is then discarded.  

so, try to prepare fresh APS and see if it'll work...

best luck

mike

Edited by jadefalcon, 21 January 2005 - 07:29 AM.

[Trinity]

Oh, it does not work!!!! I made a fresh 10% APS solution! What goes wrong?

[jadefalcon]

@trinity:

maybe you could post your "recipe" for your SDS-PAgels here and we could see if there's something basically wrong...

mike

[sankarmanicka]

After you cast the gel, do you cover the top layer with Isopropanol? because, the Acrylamide solution is sensitive to air and can rapidly form acrylic acid which will not polymerize.

As Jadefalcon points out, 90% of the cases, APS is the problem.

The acrylamide solution is also is light sensitive. When you store Acrylamide solution, make sure to use brown bottles and close it air tight and store at 4 C.

Edited by sankarmanicka, 26 January 2005 - 07:46 AM.

[Trinity]

sankarmanicka, on Jan 26 2005, 08:45 AM, said:

After you cast the gel, do you cover the top layer with Isopropanol? because, the Acrylamide solution is sensitive to air and can rapidly form acrylic acid which will not polymerize.

As Jadefalcon points out, 90% of the cases, APS is the problem.

The acrylamide solution is also is light sensitive. When you store Acrylamide solution, make sure to use brown bottles and close it air tight and store at 4 C.

Thank you very much! The APS was old!!!

[mabusheh]

Hi, may be you don't have enough Temed, check again I had the same problem and it turned out to be the Temed