Rough Quality Assessment of PS960 Oligos
By Gel

(Based on Williams, 1998.)
  1. Resuspend oligos in 85-100 ul H2O using multichannel pipettor.
  2. From a 96 well plate, I spot check about 10 random wells scattered throughout the plate. Aliquot 3 ul oligo into 3 ul of 2x sample buffer (Novex #LC6877), and mix well.
    (The Novex protocol says to heat samples for 3 min at 70oC, but from experience, it does not seem to have any observable effect on mobility.)
  3. Run out on a 15% TBE-Urea gel (Novex #EC68852) following their booklet protocol. If the bromophenol blue has already reached the conducting slot at the bottom of the gel, it may have run too far. For a control, I've been running a lane containing 300 ng of a commercial 25 mer (leftmost lane in picture below).
  4. Stain gels in 0.02% methylene blue [g/liter H2O] for a minimum of 30 min. You can save and reuse the stain for ~1 year. (Other stains may be more sensitive for single stranded DNA, but methylene blue seems to stain at the nanomol range relevant for PCR usage.)
  5. Destain with several rounds of heated H2O.
  6. Visualize on light box (visible wavelengths).

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