DNA stable in DMSO-H2O system?

[ahkian82]

In the effort of determining the binding properties of some inorganic complexes with calf thymus DNA, i have come across a solubility problem. Some of the complexes are barely soluble in aqueous solution. I noticed that DMSO can be used to aid dissolution, but how stable is the DNA in this kind of mix solvent system? To what extent, or how much DMSO can be added before the denaturation (or strand separation ??) of the ds-calf thymus DNA?

Thanks.

ahkian82

[bioinfofreak]

http://www.ou.edu/journals/dis/DIS84...ton/Colton.pdf

Stored DNA in 20% DMSO...

Basically used DMSO as a preserving buffer or ethanol if studies such as PCR are to be conducted after more than one year.

[ahkian82]

Thanks bioinfofreak..
If DMSO can be used as preserving buffer, i supposed that the DNA is stable in the DMSO-H2O (1:9 v/v) ; 50mM NaCl ; pH 7.2 solvent system. If the abovementioned assumption is wrong, please correct me. Thanks for the info.

Cheers,
ahkian82

[ahkian82]

Haha... Problem again...

The inorganic complexes are just too "stubborn" to be dissolved in the solvent system DMSO : Tris buffer (1:9). Any idea on increasing the percentage of DMSO? In this work, the DMSO doesn't play a role a preserving buffer; it is used to aid dissolution of the inorganic complexes. (However, the stability of the DNA in the solvent system used is of my very concern because the binding properties of inorganic complexes to the biopolymer could be confirmed only if there is no DNA denaturation occur during the course of the experiment. So.... DMSO percentage???

[moleculardude]

Not sure... tough question. You can try a few samples and test them with different buffers / DMSO concentrations ...