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Dna samples, Plasmid samples, Dna samples 2 plasmid samples 2 – Bio-Rad SsoAdvanced™ Universal Probes Supermix User Manual

Page 8: Store the dna at –80ºc in single-use aliquots, Prepare plasmids using an appropriate method, Store the plasmid at –80ºc in single-use aliquots

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SsoAdvanced

Universal Probes Supermix Instruction Manual

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DNA Samples

Isolate DNA using the appropriate method for the given sample type (for example, column
purification for cell lines, phenol/chloroform or column purification for tissue samples)

Store the DNA in an appropriate solution

– 0.1 mM EDTA (in DEPC-treated ultrapure water)

– TE Buffer (10 mM Tris-HCl, 1 mM EDTA, pH 7.0)

Store the DNA at –80ºC in single-use aliquots

Assess DNA quality with an agarose gel; a single band indicates high integrity DNA, whereas
a smear indicates degraded DNA

Assess the DNA purity using a spectrophotometer for the following:

– A260/A230 >1.5 (lower ratios may be attributed to carryover guanidine, and/or inhibitors

like humic acid and organics)

– A260/A280 1.7–2.0 (lower ratios are indicative of contaminants from salts, carbohydrates,

peptides, proteins, phenols, and guanidine thiocyanate)

– Higher ratios may be indicative of RNA contamination

Tips:

Heat treating DNA may be required prior to qPCR to relax strong secondary structure

Using a restriction digest enzyme may be required for select qPCR applications, such as copy
number variation, to reduce signal-to-noise ratio.

Plasmid Samples

Prepare plasmids using an appropriate method

Store the stock plasmid in an appropriate solution

– TE buffer (10 mM Tris-HCl, 1 mM EDTA, pH 8.0)

Store the plasmid at –80ºC in single-use aliquots

Assess plasmid quality with an agarose gel; a single band indicates high integrity plasmid,
whereas a smear indicates degraded plasmid or excess enzymatic activity

Assess the plasmid purity using a spectrophotometer for the following:

– A260/A280 1.7–1.9 (lower ratios are indicative of contaminants from salts, carbohydrates,

peptides, proteins, phenols, and guanidine thiocyanate)

– Higher ratios may be indicative of RNA contamination