Dear Ahmed,

I do not know if I understood your question. The method is simple. If you have a spectrophotometer, for each concentration of the solution you measure the absorbance. Then you trace the absorbance as a function of the concentration.

100 μl of the diluted solution is taken, then it is oxidized by the Folin-Ciocalteu reagent (diluted 10 times), left for 5 minutes and then neutralized with 2 ml of 20% sodium carbonate and the solutions are shaken immediately and are kept in the Dark for 30 minutes at room temperature. The absorbance of each solution is determined at 760 nm.

With my best regards

Prof. Bachir ACHOUR

I need just how to make serial dilution for six serial dilution for Gallic  acid standard phenol 0.5m ( stock solution)g down dilution to 0.05mg/ml to do standard curve

Dear Ahmed,

starting from your stock solution (500 ppm=0.5mg/ml) you have to dilute the solution in order to have a final concentration of 50 ppm (0.05 mg/ml).

Anyway, I suggest you to start from your stock solution, making for example six serial dilutions like these: 500 ppm - 250 ppm - 125 ppm - 100 ppm - 62.5 ppm - 50 ppm.

Regards

Hi Ahmed, you can simply take 1 ml from your 0.5 mg/ml and diluted it with 9 ml of distilled water. hope it helps.

I think the easy solution for this will be:

M1V1=M2V2

M1=0.5mg/ml, V1=unknown, M2=0.05mg/ml, V2=volume u want?

Similar way u can calculate for other concentrations...

You can find the solution on following video :

https://www.youtube.com/watch?v=AtMr41YT_Cw