Dear Uthreshwaranath Karnan,

Your question is rather unclear. What exactly do you want to do? For nanoparticles of this size, you can normally also use centrifugation to separate from smaller impurties or free drug. But it depends what you actually want to do and what equipment you have at your disposal.

Best regards

Robert Luxenhofer

I would use the largest cut off you can purchase to reduce the effect of the membrane.. The particles will have a much larger MW than the highest MW cut off you can purchase. You should also be concerned about the membrane material itself absorbing the drug and modifying the release rate. 

If you want to dialyze a nanoparticle formulation in order to separate the free drug by keeping the loaded particles inside the dialysis bag, a dialysis membrane with a cutoff value of 100kD works fine! (membranes with 100,000 Mw cutoff are know to have pore size around 3 nm, which ensures that 100 nm particles cannot exit the dialysis bag)

Dear  Robert Luxenhofer

        I want to be know the suitable size of the dialysis Bag is required for drug release a study.  I have a 150 KDa pore sized dialysis bag.it can be suitable for that.