A simple and convenient method for the hydrolysis of styrene-maleic anhydride copolymers to styrene-maleic acid copolymers

Styrene-maleic acid (SMA) copolymers are increasingly gaining attention in the membrane protein field due to their ability to solubilize lipid membranes into discoidal nanoparticles. The copolymers are synthesized as styrene-maleic anhydride (SMAnh), and need to be converted to the free acid form (SMA) before they are capable of solubilizing membranes. This hydrolysis reaction is traditionally performed under rather cumbersome reflux conditions. Here we report an alternative method for the hydrolysis reaction using simple and readily available equipment found in virtually all biochemical laboratories, namely an autoclave. Based on the results we propose an optimum set of standard conditions for the hydrolysis reaction, that should make the method easily accessible to a wide scope of researchers.