Difference between revisions of "Ascorbate"
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'''Preparation of 800 mM stock solution''' (dissolved in H<sub>2</sub>O): | '''Preparation of 800 mM stock solution''' (dissolved in H<sub>2</sub>O): | ||
# Weigh 1.584 g of ascorbate sodium salt and dissolve in 10 ml H<sub>2</sub>O | |||
# To prevent autoxidation, adjust pH to approx. 6 with ascorbic acid (a 137.6 mg.ml<sup>-1</sup> solution of pH 2). | |||
# Divide into 0.2 ml portions. | |||
# Store frozen at -20 °C. | |||
'''Oxygraph-2k manual titrations:''' [[MiPNet09.12]] | '''Oxygraph-2k manual titrations:''' [[MiPNet09.12]] | ||
::* Titration volume: 5 µl using a 25 µl syringe | ::* Titration volume: 5 µl using a 25 µl syringe. | ||
::* Final conc. in 2 ml O2k-chamber: 2 mM | ::* Final conc. in 2 ml O2k-chamber: 2 mM. | ||
Revision as of 06:25, 8 January 2016
- high-resolution terminology - matching measurements at high-resolution
Ascorbate
Description
In respiratory assays for cytochrome c oxidase activity (Complex IV, CIV), ascorbate is added as regenerating system for maintaining TMPD in a reduced state. As has to be titrated into the respiration medium prior to the addition of TMPD, otherwise the reaction velocity of autoxidation is permanently elevated.
Abbreviation: As
Reference: MiPNet06.06
MitoPedia topics: Substrate and metabolite
Application in HRR
As: Ascorbate sodium salt (Sodium L-ascorbate); Sigma A 4034, 100 g, store at RT; FW = 198.1.
Caution: Light sensitive (store solution in a dark glass vial).
Preparation of 800 mM stock solution (dissolved in H2O):
- Weigh 1.584 g of ascorbate sodium salt and dissolve in 10 ml H2O
- To prevent autoxidation, adjust pH to approx. 6 with ascorbic acid (a 137.6 mg.ml-1 solution of pH 2).
- Divide into 0.2 ml portions.
- Store frozen at -20 °C.
Oxygraph-2k manual titrations: MiPNet09.12
- Titration volume: 5 µl using a 25 µl syringe.
- Final conc. in 2 ml O2k-chamber: 2 mM.
