Liquid seperation of B-carotene and Chlorophyll-a

[dibilo]

Hi all, I have just done a liquid separation of B-carotene and Chlorophyll-a and put the 2 samples through a UV spectrometer.

The result that I get from the meter for B-carotene is 448nm for 1st peak and 475.1nm for 2nd peak.

For Chlorophyll-a my peaks are at 417.9nm and 666.1nm.

But I have a few questions here. Why are there 2 peaks for each of them? Is it normal? Is it due to the presence of impurities? Is it due to me not choosing the appropriate blank for the UV spectrometery test?

For the case of B-carotene, the 2 peaks are so close together which means they have really poor resolution. Is it normal?

Thanks in advance for anyone who can offer me a little guidance.

Regards,

dibilo.

 

[GCT]

B-Carotene and Chlorophyll-a are conjugated organic molecules, the excitation spacing (pi to pi) for B-Carotene is closer together in the visible region since it's more conjugated. A lot of this stuff can be explained quantitatively by the particle in a box model.

You can ascertain the color of the solution by employing color methods, the two peaks represent the wavelengths that the molecule absorbs, familiarize yourself with some of the basic principles of "color theory" to understand why B-Carotene appears orange, for instance.

 

[Blueshift5]

Hello dibilo,

Thank you for sharing your results from the liquid separation of B-carotene and Chlorophyll-a. It is normal to see multiple peaks for each compound in a UV spectrometer, as each peak corresponds to a specific wavelength at which the compound absorbs light. The presence of multiple peaks can be due to impurities, but it can also be a result of the complex structure of these compounds.

In order to accurately interpret your results, it is important to ensure that your blank is appropriate for the UV spectrometer test. The blank should have the same solvent and concentration as your samples, but without the compound of interest. This will help to eliminate any interference from the solvent or other compounds.

The close proximity of the peaks for B-carotene may indicate poor resolution, which can be affected by factors such as the instrument settings and sample preparation. It may be helpful to consult the instrument manual or seek assistance from an experienced colleague to optimize the resolution for your samples.

Overall, your results seem to be in line with expectations for these compounds. Keep in mind that UV spectrometry is just one technique for analyzing compounds, and it is important to consider other factors such as sample purity and concentration when interpreting your results. I hope this helps to guide you in your research. Best of luck!

Sincerely,