Lidstrom:Solution Stock Info

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(From Book referenced below)
(Recommendations)
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==ATP==
==ATP==
* Mila said ATP doesn't degrade into ADP or AMP, and ADP doesn't degrade into AMP either.  Enzymes are required for these interconversions.  You can keep stocks at -20oC.  -[[User:Janet B. Matsen|JM 12/17/2013]]
* Mila said ATP doesn't degrade into ADP or AMP, and ADP doesn't degrade into AMP either.  Enzymes are required for these interconversions.  You can keep stocks at -20oC.  -[[User:Janet B. Matsen|JM 12/17/2013]]
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====Recommendations====
+
====Recommendations from 1993 book below====
*ATP, sodium salt (MW 551)
*ATP, sodium salt (MW 551)
**Store desiccated powder @ -20°C
**Store desiccated powder @ -20°C

Revision as of 11:19, 18 December 2013

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Contents

ATP

  • Mila said ATP doesn't degrade into ADP or AMP, and ADP doesn't degrade into AMP either. Enzymes are required for these interconversions. You can keep stocks at -20oC. -JM 12/17/2013

Recommendations from 1993 book below

  • ATP, sodium salt (MW 551)
    • Store desiccated powder @ -20°C
    • In H2O, bring to pH 7, with 2 equiv NaOH, store -20°C
    • Stable for months with minimal concentration loss

NAD(P)/H

  • When NADH degrades, it turns yellow. It is not degrading into NAD, though; it degrades into something else. From Mary & Mila 12/17/2013 -JM

From 1993 book referenced below

  • NAD(P)H are rapidly destroyed in acid in conditions where NAD(P)+ are completely intact
  • 99% destruction of NADH
    • @23°C = 1.2 min @ pH 2, = 2 hr @ pH 4
    • @38°C, 3-4x faster
    • @60°C, 20x faster
  • NADPH is destroyed faster than NADH (~80% faster @ 30°C)
  • @pH 2, NAD+ is 100,00x more stable than NADH
    • Allows elimination of reduced form by pH drop
  • Above pH 7, degradation rate of NAD increases,5000x faster at pH 12.5-13
  • NADP+ appears to be more stable than NAD+
  • Higher temp, more salts increase degradation rate
  • NADH becomes more stable with pH increases, excluding low concentration in small volumes
  • Oxidation is a problem above pH 8
  • @ pH 7 25°C, rate of destruction in ~0.2%/hr, increases 10x @ pH 6
  • Strong solutions (40 mM) of NADH store well @ pH 9-12, but large losses @ 4°C
  • Weak solutions (0.4 mM) of NADH store well @ 4°C from pH 9-11, destroyed @ -20°C pH >10.5
  • Similar characteristics for NADPH
  • NADH presence in small volumes is sensitive to oxidation at neutral pH
    • increases ~inverse square root of the volume
    • can prevent with 1 to 2 mM ascorbic acid

Recommendations

  • Store pyridine nucleotides, desiccated @ -20°C
  • Can store NAD+/NADP+ solution for months without significant concentration change/
  • Can standardize stock solutions with spectrophotometer
  • Dissolve NAD+/NADP+ in water, ~100 mM
  • Unless < -40°C, NAD(P)H should be prepared at < 5 mM, pH 9-11 and stored at 4°C. At low temp, strong solution can probably be stored without too much loss

Citations

Passonneau, J. V., Lowry, O. H., & Lowry, O. H. (1993). Enzymatic analysis: A practical guide. Totowa, NJ: Humana Press.

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