Go Back   Science Forums Biology Forum Molecular Biology Forum Physics Chemistry Forum > Molecular Research Topics Forum > Molecular Biology Techniques > Agarose Gel Electrophoresis Forum
Register Search Today's Posts Mark Forums Read

Agarose Gel Electrophoresis Forum Agarose Gel Electrophoresis Forum. A forum to discuss electrophoresis staining, troubleshooting, and development of films for DNA and RNA gels.


DNA bands disappear

DNA bands disappear - Agarose Gel Electrophoresis Forum

DNA bands disappear - Agarose Gel Electrophoresis Forum. A forum to discuss electrophoresis staining, troubleshooting, and development of films for DNA and RNA gels.


Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 01-12-2010, 03:29 AM
Pipette Filler
Points: 64, Level: 1 Points: 64, Level: 1 Points: 64, Level: 1
Activity: 0% Activity: 0% Activity: 0%
 
Join Date: Jan 2010
Posts: 1
Thanks: 0
Thanked 0 Times in 0 Posts
Default DNA bands disappear



Hi..
My PCR product is 190 bps.. it becomes faint and disappears during electrophoresis
Can anyone tell me possible reasons
Reply With Quote
  #2  
Old 01-12-2010, 08:40 PM
Aga's Avatar
Aga Aga is offline
Post-Doc
Points: 2,239, Level: 30 Points: 2,239, Level: 30 Points: 2,239, Level: 30
Activity: 0% Activity: 0% Activity: 0%
 
Join Date: Nov 2008
Posts: 270
Thanks: 25
Thanked 78 Times in 64 Posts
Default Re: DNA bands disappear

It is possible that you load to little DNA so after some time of migration the band stretches and disappears. Or you use too little ethidium bromide to stain it.
Reply With Quote
  #3  
Old 01-12-2010, 10:06 PM
Moleecule's Avatar
Pipette Filler
Points: 2,272, Level: 30 Points: 2,272, Level: 30 Points: 2,272, Level: 30
Activity: 0% Activity: 0% Activity: 0%
 
Join Date: Jan 2007
Location: San Jose
Posts: 13
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: DNA bands disappear

You might be running the gel too long- EtBr runs out of the lower gel portion first. Or gel percentage is too low and the fragment runs as a diffuse band..
Reply With Quote
  #4  
Old 01-13-2010, 02:42 PM
butters's Avatar
M.D/Ph.D
Points: 4,938, Level: 47 Points: 4,938, Level: 47 Points: 4,938, Level: 47
Activity: 0% Activity: 0% Activity: 0%
 
Join Date: Dec 2008
Location: Malaysia
Posts: 315
Thanks: 25
Thanked 68 Times in 63 Posts
Default Re: DNA bands disappear

@wishmaes, can u show us the gel?

DNA migration is from black to red. etbr is from red to black thus longer u ran the gel the less etbr will be at red part of the tank. That is the part where ur low molecular weight DNA will be at the end of the run. It occured when u ran a pre-stain gel. the easiest way is to look at ur ladder. does the 100bp or 200bp is faint and almost disappear? However if the ladder band for 100bp or 200bp is very strong thus it is not related to etbr or running too long. so if possible show us the gel with the ladder beside the pcr product and tell us how much u load. thank!
Reply With Quote
The Following 2 Users Say Thank You to butters For This Useful Post:
Aga (01-13-2010), Malkor (02-03-2011)
  #5  
Old 01-15-2010, 06:22 PM
Pipette Filler
Points: 1,128, Level: 19 Points: 1,128, Level: 19 Points: 1,128, Level: 19
Activity: 0% Activity: 0% Activity: 0%
 
Join Date: Oct 2008
Location: India
Posts: 22
Thanks: 1
Thanked 2 Times in 2 Posts
Default Re: DNA bands disappear

You should use atleast 2 % gel and run it with less voltage. Then you may see the bands.
Reply With Quote
  #6  
Old 05-10-2010, 12:13 PM
Pipette Filler
Points: 1,688, Level: 24 Points: 1,688, Level: 24 Points: 1,688, Level: 24
Activity: 0% Activity: 0% Activity: 0%
 
Join Date: May 2010
Posts: 21
Thanks: 0
Thanked 8 Times in 7 Posts
Default Re: DNA bands disappear

Quote:
Originally Posted by butters View Post
@wishmaes, can u show us the gel?

DNA migration is from black to red. etbr is from red to black thus longer u ran the gel the less etbr will be at red part of the tank. That is the part where ur low molecular weight DNA will be at the end of the run. It occured when u ran a pre-stain gel. the easiest way is to look at ur ladder. does the 100bp or 200bp is faint and almost disappear? However if the ladder band for 100bp or 200bp is very strong thus it is not related to etbr or running too long. so if possible show us the gel with the ladder beside the pcr product and tell us how much u load. thank!
I will agree with you totally. Prolonged run of a gel, means that you EtBr will migrate off your gel, and QQ then for your bands. In that case you might be able to restain your gel with EtBr, though is not recommended. Also check the intensity of your UV lamps. It has been reported that prolonged exposure of a DNA gel under a strong UV lamp may diffuse and ultimately disappear your DNA bands.
Reply With Quote
Reply

Tags
bands , disappear , dna


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
negative bands problem SallyG SDS-PAGE Gel Electrophoresis Forum 4 07-06-2010 08:03 PM
Leaf + Root sample on 1D sds gel leads to high molecular bands to disappear !!!!!!!!! Maniche SDS-PAGE Gel Electrophoresis Forum 0 05-12-2010 05:29 AM
Increase Exposure, Bands Disappear?? Mediatorx Western Blot Forum 3 07-01-2008 09:18 PM
Help Migrating bands camherst Western Blot Forum 1 01-26-2008 02:48 PM
Artifactual double bands Natalia Oliveira Protocols and Methods Forum 1 09-08-2007 11:28 AM


All times are GMT. The time now is 05:11 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2005 - 2012 Molecular Station | All Rights Reserved
Page generated in 0.14469 seconds with 16 queries