Dear Colleague;
Please help me to solve the problem of my experiment concerning the anti-inflammatory activity with the Griess reagent and sodium nitroprusside.
I repeated the experiment more than a month but I find that the percentages of inhibition decrease with the increase of the concentrations.
I prepared the Griess reagent as follows;
1% sulphanilamide in 2.5% orthophosphoric acid, .1% N- (1-naphthyl) ethylenediamine dihydrochloride in distilled water.
both solutions are kept separately. I mixed volume / volume during the use
The protocol:
0.5ml extracts (different concentrations from a stock solution of 1mg / ml) + 0.5 ml sodium nitroprusside (10mM in phosphate buffered saline (pH 7.4)
incubation at 25 ° C for 2.5h.
then I added 1ml of Griees reagent (1ml), incubate 30min at 25 ° C.
Read the absorbances at 546nm of the tests and the control against the blanc which is formed of the distilled water.
Here are the values obtained:
C (mg / ml) % inhibition
1 4.373698304
0.5 10.7606863
0.25 16.05672915
0.125 15.54100962
Dear DR Benhammou; at your place I will do a centrifugation before reading and prepare also a gallic acid standard curve.
cordially
- Badges
- Science topic
- Similar topics
- Phytochemistry
- Extracts