I hav taken absorbance of FESO4 at range of 2.5-200 uM which show linearity with R2=O,98...then i took absorbance of standard/extract at different conc .....how to get FRAP activity...show me calculation?.
Dear Vikas,
In the calibration curve you plot absorbance vs. concentration in uM. Then you take the absorbance that you measured for the extract and find its concentration according to the curve. The same you repeat for the standard.
For example if the curve you got from plotting absorbance vs, concentration gave an equation such as:
Absorbance = K (concentration) + A; where K (for example 0.5) is the slop of the curve and A is a number (for example 1.0), to find the concentration for the extract that gave an absorbance of 1.4 for example you will do the following:
1.4 = K (concentration) + A; therefore Concentration = 1.4-A/K; since A and K are known numbers; you replace A and K with their values and get
Concentration = 1.4-1/0.5=0.8uM
The same calculation you will do for the standard. If you want to get the ratio of extract/standard you divide the concentration of the extract/ concentration of standard.
Hoping this will be helpful,
Rafik
Yeah..it works..bt there is a confusion regarding the formula o.d test/o.d standard*FRAP value of standard..which is 2000 for 1000uM..bt i use different concentration of Feso4 from 2.5-20 uM only...then wat FRAP value i use..will it 20...??
Hi Dr Chibuike Udenigwe,
Can you help me for the calculation part. I am stucked..
For example, my sample has a FRAP value og 1.53 mM FE.. Then, I want to express it in mM Fe/g DW.. So how?
Thank you.
- Badges
- Science topic
- Similar topics
- Phytochemistry
- Extracts