INFLUENCE OF SODIUM CHOLATE ON THE CRYSTALLIZATION OF CALCIUM-OXALATE

Spontaneous, unseeded batch precipitation of calcium oxalate from aque ous solutions containing different concentrations of sodium cholate wa s followed at the conditions mimicking those in urine. Formation of ca lcium oxalate dihydrate in the systems where, in the absence of additi ve, calcium oxalate monohydrate is the only solid phase formed is clea rly demonstrated. Depending on the structure of bile salt aqueous solu tions, different influence on the overall crystallization yields is ob served. Crystal growth inhibition in some systems could be attributed to the changes in the surface energy due to the adsorption of cholate on the surface of growing crystals. The retarding effect on crystal ag gregation, observed in all investigated cholate-containing systems, mi ght be of special importance from a biomedical point of view, since ag gregation has been pointed out by many authors to be a crucial step in urolitihiasis.