Dear Aakash Ll,

Zein receives its typical yellow colour due to its content of carotinoid pigments, mainly lutein and zeaxanthin (Sessa et al., 2003). The carotinoids absorb with a characteristic three-peak spectrum in the visible range (Fig. 25), thus the pigment content was quantified by the UVabsorbance in the visible range at the wavelength of the maximum absorbance of the carotinoid chromophore at λ = 445 nm.

In order to determine to calculate the amount of zein dissolved in a solution, you should make a standard solutions at different concentration and then measure the absorbances of these solutions at λ = 445 nm and plot a curve of absorbance vs. concentration.

Measure the absorbance of the zein sample dissolved by surfactant at  λ = 445 nm and calculate the concentration using the standard curve,

The equation to be used is:

Concentration of Zein sample/Concentration of Zein Standard = Absorbance of Zein sample at λ = 445 nm/Absorbance of Zein standard at λ = 445 nm.

For more information on the UV-vis of zein, see page 96-97 in the publication contained in the following link:

http://www.diss.fu-berlin.de/diss/servlets/MCRFileNodeServlet/FUDISS_derivate_000000002347/3_4-results-zein.pdf?hosts=

Hoping this will be helpful,

Rafik

Dear Anwar,

The question was on Zein solutions and NOT suspensions. Zein solutions have Uv-vis spectrum which is illustrated in the file contained in the link indicated in my answer.

Rafik

Thank you very much Rafik!

Thanks Anwar too!

Suppose I make a 5% active solution of a surfactant (say Sodium Dodecyl sulfate). Now, I put 5g of zein in 100g of such solution then the zein will be dissolved as per the surfactant harshness. Will the dissolved form of zein be a suspension or solution? Can I use UV-absorbace ?

I think this link is useful, 

http://www.instanano.com/characterization/theoretical/concentration-calculation-from-uv-vis-absorbance/