Method and device for evaluation of pharmaceutical compositions

A method for evaluating a pharmaceutical composition comprising a drug, said method comprising:

• (1) providing a microporous membrane having a plurality of pores, said membrane being made from a hydrophobic material, and said membrane having a hydrophilic feed side and a permeate side, wherein said feed side of said membrane is in fluid communication with a feed solution, and wherein said permeate side of said membrane is in fluid communication with a permeate solution;
• (2) administering said pharmaceutical composition to an aqueous solution to form said feed solution;
• and
• (3) measuring the concentration of said drug in said permeate solution;
• wherein said permeate side of said microporous membrane has a contact angle for a drop of water of greater than about 90° and said feed side of said microporous membrane has a contact angle for a drop of water of less than about 70°, and wherein said permeate solution comprises an organic fluid that is substantially immiscible with water.