If what you meant was that you want to remove the sulphate from the nanozyme, then if the nanozymes have a high molecular weight (e.g. 10,000) there are a few methods you can use in an aqueous medium to separate the nanozymes from the magnesium sulphate: dialysis or gel filtration chromatography.

thanks a million for your guidance, the nanozyme is based on cyclodexterin and I'm looking for a solvent to separate sulphate .

How much stuff do you have; mg, g, kg?

I have about 0.5mg of the nanozyme.

A small gel filtration column could do the job.

https://www.bio-rad.com/featured/en/gel-filtration-column.html

thanks a million for your answer.