(684a) Polymorphic Selection of Biominerals By Anionic Polyelectrolytes

In most biomineralization processes many soluble biopolymers exist in minute quantities; these control the nucleation, growth, orientation, and polymorph selection, leading to the formation of minerals with diverse biological functions and distinct properties but also to pathological mineralization, e.g., bone disease, dental calculus, and renal stone formation. In this work, we study the effects of supersaturation, temperature, and additives on the nucleation and growth of calcium oxalate (the major constituent of kidney stones) in aqueous solutions. We have demonstrated that certain anionic polyelectrolytes can be very effective toward kidney stone inhibition by reducing the growth rate, altering the crystal morphology, and favoring the formation of the metastable dihydrate (COD) over the thermodynamically stable monohydrate (COM) which is mainly responsible for kidney, gall, and bladder stones. We compare our results to citrate, a naturally occurring inhibitor in the urinary system and currently the standard pharmacological treatment for stones. Our findings offer a better understanding of the calcium oxalate crystallization kinetics and provide information on the viability of synthetic polymers as potential calcium oxalate stone therapies.