Question

It’s often useful to compare the “theoretical basis” for two techniques when deciding which to choose. Let’s compare absorbance and fluorescence measurements. Assume that the analyte both absorbs and fluoresces.

a. Explain why, on a “theoretical basis”, we might expect that absorbance would be more sensitive.

b. Explain why we might expect that fluorescence would be more sensitive.

c. In practice, fluorescence is typically more sensitive. Considering how the instruments are built and how the experiment is done, explain why fluorescence is more sensitive.

Answer 1

a) On theoretical basis, absorbance is more sensitive becasue the measurement of absorption and independent on the spectrometer. We can use this technique to detect the unknown compounds by using this technique. It depends on the absorbance.

b) Fluorescence is a cyclic process. There is a no wastage of the compound, we can use it more more and more times for the same compound. It depends on the excitation and emission of electron in a compound.

c) It is more sensitive because of wide range of spectra's are giving different types of information on same compound. We can analyse the compound easily.