Do you have the possibility to calculate only the silymarin? Are you encapsulating pure silymarin or an extract? First, you have to perform purification of your nanoparticles, for example with centrifugation. Then, you can take a sample of the nanoparticles, disrupt them, and then use UV or HPLC to quantify the molecule or extract.

Dear David

My extract (silymarin) is not pure. for encapsulating, I have to dissolve it in ethanol and then mix with alginate and CaCl2. One of my friend said to me that " measure phenol content of your extract (X), after capsulation and centrifuge take a sample from supernatant to measure phenol content (Y). then use this equation: EE% = X-Y / X *100

Your idea? 

Yes, you can use total flavonoid to calculate the encapsulation efficiency. We take samples before and after centrifugation. After centrifugation from pellet and supernatant. Your pelet+supernatant must be equal to the sample before centrifugation. 

From pellet and supernatant? or only from supernatant? I think just supernatant.

In other word, first I dissolve my powder (silymarin) in ethanol and from this liquid I measure phenol.

Then I use this solution for encapsulation. After centrifugation, from supernatant phenol content is measured.

Is that OK?

We usually sample both because we want to make sure the addition is equal to the total amount of substance we added. If you want to sample before cntrifugation and after centrifugation the supernatant is okay. You have to measure before centrifugation too, or if you want, you can make an theoretical assumption.

In other words:

1. Encapsulate your extract

2. Sample before centrifutation.

3. Centrifugation.

4. Sample supernatant.

5. Sample preparation to measure total phenolic content.

Hi,

What concentration of sodium citrate did you use?

Use 55 mM sodium citrate during 1 h of incubation.

Phenolic content is a possibility but I would prefer a isolated compound of the all extract.

Use direct and indirect method, i.e., supernatant after production and centrifugation at least 30000 x g and by disrupting polymeric matrix.

Best regards,

CReis

Hi, the indirect method is usually used for encapsulation with alginate. As you are encapsulating an extract, my suggestion is to quantify the substance of interest . In order to open the alginate use a chelating calcium.

best regards

I agree with previous answers. Good luck!

Dear Catarina Reis

Dear Finotelli

I will use the indirect method with this equation: X-Y / X * 100

My problem is X.

which one of the below subjects can be used as X:

1- phenol of dissolved extract in ethanol (i.e before encapsulation)

2- phenol in suspension I have made (i.e after encapsulation and before centrifugation) 

thanks

You can investigate the three:

1. Before encapsulation

2. After encapsulation + before centrifugation

3. Afnter encapsulation + after centrifugation (supernatant)

And calculate how much of your extract remain in the pellet after knowing the supernatant content, the before centrifugation content and the before encapsulation. You have one X, and that should be "3" (indirectly you know your pellet content) and 2 "y", and they are 1 and 2.

Maybe you can draw the steps and then make the proper relationships between the measurements.

Use silibin peak as marker