During my handling, the white perform during the test was not stable, and the decay time doubled from one day to the next as it became more of a white antioxidant. We thought it was a contamination, but different washing optical tanks quartz (ethanol, acetone or both) have not abolished the randomness of the blank value. In addition, we used Cavasol (beta cyclodextrin) for lipophilic extracts, in which case these variations are accentuated.
Does anyone have an idea or explanation?
Extraction and analysis of hydrophilic and lipophilic antioxidants, is done by using
modifications of the oxygen radical absorbing capacity (ORACFL) procedure. These methods provide, assist to obtain a measure of “total antioxidant capacity” in the protein free plasma, using the same peroxyl radical generator for both lipophilic and hydrophilic antioxidants. Separation of the lipophilic and hydrophilic antioxidant fractions from plasma can be accomplished by extracting with hexane after adding water and ethanol to the plasma (hexane/plasma/ethanol/water, 4:1:2:1, v/v). Lipophilic and hydrophilic antioxidants can be efficiently partitioned between hexane and aqueous solvents. Conditions for controlling temperature effects and decreasing assay variability using fluorescein as the fluorescent probe can be validated. Incubation (37 °C for at least 30 min) of the buffer to which AAPH can be dissolved remains critical in decreasing assay variability.
Use randomly methylated â-cyclodextrin (RMCD) as a solubility enhancer.
Organic solvents are not compatible with the aqueous ORAC assay system. Naguib developed an organic solvent system for assay of lipophilic antioxidants using BODIPY 581/591 or BODIPY 665/676 as the fluorescent probe and 2,2′-azobis-2,4-
dimethylvaleronitrile (AMVN) as the peroxyl radical source.
thanks a lot for your answer
can you give me some information about the naguibs paper becaause i didn't find it on web site
- Badges
- Science topic
- Similar topics
- Agriculture
- Horticulture
- Seeds