Chemical Forums

Chemistry Forums for Students => Analytical Chemistry Forum => Topic started by: L v lion on April 08, 2021, 07:16:34 AM

Title: How to decapsulate a compound out of micelles?
Post by: L v lion on April 08, 2021, 07:16:34 AM
Hello,

I am developing a redox titration method to assay sodium selenite in a pharmaceutical product. The method that I have developed is a redox back titration with iodine 0.1N and sodium thiosulfate 0.1 N as titration solution. The problem with the titration is that my recovery is to low. After some research it seems that the emulsifiers are forming micelles. This micelles encapsulate the sodium selenite. The emulsifiers are Polysorbate 80 and Sorbitan stearate. Does anyone knows how to decapsulate the sodium selenite out of these emulsifiers? 
Title: Re: How to decapsulate a compound out of micelles?
Post by: jeffmoonchop on April 08, 2021, 11:45:08 AM
Try Triton
Title: Re: How to decapsulate a compound out of micelles?
Post by: shchavel on April 12, 2021, 02:07:14 AM
Hello!

What method do you use for indication final point of titration? Polysorbate 80 interacts with starch indicator, so it doesn't work with your mixture. Be careful with it.
Title: Re: How to decapsulate a compound out of micelles?
Post by: L v lion on April 12, 2021, 10:10:09 AM
Try Triton

I read that Triton is a hazardous chemical. Is there a safer compound that can also work?
Title: Re: How to decapsulate a compound out of micelles?
Post by: L v lion on April 12, 2021, 10:23:14 AM
Hello!

What method do you use for indication final point of titration? Polysorbate 80 interacts with starch indicator, so it doesn't work with your mixture. Be careful with it.

I am not using a indicator. I am doing the titration with a combination platinum electrode. The final point of the titration is determined potentiometric.
Title: Re: How to decapsulate a compound out of micelles?
Post by: jeffmoonchop on April 12, 2021, 11:51:49 AM
We use Triton every day to de-encapsulate mRNA in lipid nanoparticles. You will only need a tiny amount, we use 30ul in 3ml cuvette, wont matter much the concentration of particles. Just wear gloves. I read there are alternatives but I'm sure you can google.