Daniel:Notebook/HiResChrPaint/2013-7-23

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Revision as of 22:26, 23 July 2013 by >Djacobse (→‎Column Loading Trial)
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S2 Probe Preparation (Started 7/22/2013)

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DpnII Digestion (from 7/22/2013)

3. Pool samples for V4 set into 4AB and 4CD
4. Column Purification, elute with 30 uL EB**
5. Pooled 4AB and 4CD into V4S2 and pooled V6 sets into V6AB and V6CD
6. Measure concentrations in nanodrop

Note (**): Forgot to move the columns to fresh tubes before elution. Caught myself just as the centrifuge started, so I stopped it immediately, before it even got to full speed. Still, this resulted in me losing most of the samples (I also threw away the collection tubes before proceeding to the fresh collection tube).

Nanodrop Results

Sample V4S2 V6S2AB V6S2CD
ng/uL 142.9 32.8 34.9
ug in 20 uL 2.9 0.7 0.7
total ug     1.4

DpnII Digest gel

1. Lanes; (5.5 uL TBE; 2 uL 6x buffer, 0.5 uL sample; load 7 uL for all)


Lane 1 2 3 4 5 6 7 8 9 10 11 12
Sample 25bp ladder V4S2 V6S2AB V4S2CD

Gel Image

File:DpnIIDigest 72313.jpg

Discussion

Since I botched this probe prep, I may have to start over. I still have to digest with lambda exonuclease, which is going to drop my concentrations by 50% regardless. This would mean I'd likely have <1 ug for both V4S2 and V6S2 prior to dye coupling. It's just not worth it. I'm going to store these probes, and the next time I make a S2 set I'll add the probes in post DpnII digestion.

Column Loading Trial

I talked with Noi about why we always do an ethanol precipitation after PCR, because we do a column prep anyway. As far as we can tell, the ethanol precipitation condenses the volume so that we don't have to use a lot of columns. I think, however, that we can load the column several times and get the same result. To test this, I'm going to run the same amount of DNA on two different columns. I'll load one once (haploid) and one twice (diploid). For this I'm going to use the AmpF probes that Noi gave me (~50 bp, 1392.5 ng/uL).

1. Add 100 uL nfH2O to hap and 200 uL nfH20 to dip
2. Add 2 uL AmpF to each (~3 ug)
3. Add 600 uL PB to hap and 1200 uL PB (requires 2x spins)
4. Elute with 40 uL PB
5. Measure with Nanodrop

Nanodrop Results

  ng/uL ug in 40 uL Yield %
Haploid 12.8 0.5 17.1
Diploid 11.1 0.4 14.8

Discussion

Although n is only equal to 1, it looks as though multiple loading the column is no problem. This will save on time, as the ethanol precipitation used up at least 4 hours incubation (probably overnight is better) as well as an hour or so centrifugation.

S2 Probe Prep

I'm going to retry