I'm working with leaves for the determination of Total Phenolic Content and for quantifying this is necessary a standard curve of gallic acid. Could you give some options about concentration?
Usually a standard curve from 0 to 200 mg/L works good,, with gallic, chlorogenic and ferulic acid since the absorbance of the máximum point is between 0.6 and 0.7.
You can check this paper for protocol of phenolics and antioxidant capacity assays
Interesting Mr. Guillermo. I have some doubt, some papers about phenolic content show concentrations for a standard curve of gallic acid like: (1) 1.57 ug - 15.7 ug, (2) 0 - 10 mg/ml, (3) 0 - 165 mg/L, (4) 0.05 - 0.40 mg/ml, and finally (5) 0 - 500 mg/L from the professor Aly R.
Would you say this concentration range (0 - 200 mg/L) is recommended to quantify phenolics in leaves anyway? Well, you worked with chickpea and soybean hulls.