Spectrophotometric measurement of RNA quantity
Started by Erik Edstrom, Jun 14 2002 12:53 AM
2 replies to this topic
#1
Posted 14 June 2002 - 12:53 AM
I'm using the Trizol protocol for total RNA extraction. When quantitating the RNA (diluted in highly purified water) I sometimes get low 260/280 ratios. The product troubleshooter suggests that this may be due to dilution of RNA in water and not TE. Does anyone know what this TE is or have a good suggestion regarding what solutions should be used for diluting the RNA when measuring at 260nm?
#2
Posted 14 June 2002 - 04:12 AM
TE is a solution of Tris and EDTA 10:1.
You can prepare a solution 10 mM Tris-HCl + 1 nM EDTA at different pHs.
EDTA is always pH 8.0, and Tris can be at 7.4, 7.6 or pH:8.0.
Personnally, i don't use TriReagent or Trizol anymore, because there is too many possibility of poor yields because of many steps and contamination with DNA and proteins. If you can, use commercial kits like Quiagen RNAeasy, which doesn't use phenol, is very quick, and gives good 260/280 ratios.
You can prepare a solution 10 mM Tris-HCl + 1 nM EDTA at different pHs.
EDTA is always pH 8.0, and Tris can be at 7.4, 7.6 or pH:8.0.
Personnally, i don't use TriReagent or Trizol anymore, because there is too many possibility of poor yields because of many steps and contamination with DNA and proteins. If you can, use commercial kits like Quiagen RNAeasy, which doesn't use phenol, is very quick, and gives good 260/280 ratios.
#3
Posted 14 June 2002 - 08:51 AM
Sorry, it is 1mM EDTA and not 1 nM... (10:1)













