Hi,

For your question, kindly see the following:

http://derpharmachemica.com/vol5-iss3/DPC-2013-5-3-44-50.pdf

Hello!

You can use extinction coefficient  and The Beer–Lambert law

• e = D/(c*l)

e - extinction coefficient; D -  absorbancy;  c - concentration of oleanolic acid; l - optical path

Miss/Mrs. Sohrabi,

In general the problem is that the lmax is at 205 nm in H2O (Please pay attention on the attachment), which is shifted to 216 nm in C2H5OH. Given that, during the intergration of the spectroscopic pattern you have lost an information about the real intensity of the band.

In this respect you should operate below 200 nm, which can be achieved using the shown in the attachment windows for the cuvette cellars, including inert conditions.

You could try to determine the analyte in H2SO4 as well using the quartz cuvette cells, because of the lmax is about 310 nm

Please check the link below and I hope to be useful to you

http://derpharmachemica.com/vol5-iss3/DPC-2013-5-3-44-50.pdf