Stabilization of amorphous indomethacin by co-grinding in a ternary mixture.

Mechanochemical amorphization of indomethacin (IM) was substantially enhanced by grinding with SiO(2), talc and a Mg(OH)(2)-SiO(2) mixture. The rates of the mechanochemical amorphization were in the order of Mg(OH)(2)-SiO(2) mixture>talc>SiO(2). Amorphous state stability of IM compounded with the carrier was examined by crystallization behavior under the condition of 30 degrees C and 11% relative humidity. Superiority of the binary mixture as a carrier was explained in terms of the mechanically induced strong acidic sites of the carrier.