Bradford is not an option for your case.

If you need to perform Bradford protein quantitation,

You may perform dialysis or buffer exchange protocols to get rid of them. Dialysis bag or slide-a-lyzer dialysis cassettes g2 are very practical to use. İnstead of dialysis more efficient one is the ultrafiltration approach using centrifugal filter units with suitable membrane cut off values.

It is also possible to use desalting cartridges adapted to a stand-alone system with SPE format or implemented as a column to the FPLC system. Size exclusion resins are also beneficial for these physical purification strategies.

I hope these would be helpful for your project,

Good Luck,

Emir...

You will never be able to completely remove surfactants using dialysis or ultrafiltration. The former will take forever. Both suggestions will not get rid of micelles. Moreover you are dissolving the liposomes by the hydrophobic effect (protein will also bind the surfactant by the same effect provoking its denaturing), there is no way you can reverse this bonding using plain water as thermodynamics kick in. As for sec it will also not work for this same situation, you will be able to perhaps separate micelles from free surfactant, not sure though.

Dear Researcher,

You can use direct methods to evaluate loading efficiency and conjugating value as well. There are some analytical devices, including TGA, HNMR, and XRD to implement this efficiency. You can use the following manuscripts as well:

Article Breast Tumor Targeting with PAMAM-PEG-5FU-99mTc As a New The...

Article Synthesis and evaluation of polyethylene glycol- and folic a...

Article Targeting delivery of Oxaliplatin with smart PEG-modified PA...

In the case of general approaches are ineffectual,

Have a look at the following discussion. The protocol has been discussed may be useful for your research; https://www.researchgate.net/post/Which_are_the_best_methodologies_to_extract_protein_from_liposomes

Ion exchange chromatography may also help for detergent monomers removal, but detergents with low CMC (e.g., Triton X-100, Triton X-114, NP-40) are more difficult to remove from a solution since they bind strongly with protein molecules and that cannot be removed by gel filtration or dialysis. GBio’s DetergentOUTGBS10 resin may help for this purpose you may take a look at the link below;

https://www.gbiosciences.com/Protein-Research/Detergents-Accessories/Detergent-Removal-Systems/DetergentOUT-GBS10

At last but not least;

for lipids and ionic contaminants, 2D Clean-up kits ( e.g. ReadyPrep™ 2-D Cleanup Kit -TCA precipitation based) combined with RC-DC protein quantitation using BioRad reagents should be also evaluated, please find the informations below;

https://www.bio-rad.com/en-uk/product/rc-dc-protein-assay?ID=f58fdf1d-5d0b-4f31-93e2-f812bd7e7eab

https://www.bio-rad.com/en-uk/product/readyprep-2-d-cleanup-kit?ID=bbf3a0be-188f-45c7-b81e-e9706ec77c02

thanks all for the input and the suggestions, i appreciate it a lot! And sorry for the late answer!

the main problem (e.g. dialysis) is the small concentration level, so I must prevent dilution steps. (Often I have heard to dilute the sample for reducing interference but that is not an option).

İsmail Emir Akyildiz , İsmail Emir Akyildiz ...thanks for the manuscripts I will look for it, but I am not sure, if we have the opportunities and the budget for this in our lab.

Omar Gonzalez-Ortega do you know any other quantification method in which the lipids/detergents for destruction the liposomes not interfere? BCA assay is compatible with Triton I know it, but the Lipid intereference is the same problem too.