EFFECT OF SIMULTANEOUSLY SILICIFIED MICROCRYSTALLINE CELLULOSE AND PREGELATINIZED STARCH ON THE THEOPHYLLINE TABLETS STABILITY.

High profitability and simplicity of direct compression, encourages pharmaceutical industry to create universal excipients to improve technology process. Prosolv® SMCC - silicified microcrystalline cellulose and Starch 1500® - pregelatinized starch, are the example of multifunctional excipients. The aim of the present study was to evaluate the stability of theophylline (API) in the mixtures with excipients with various physico-chemical properties (Prosolv® SMCC 90, Prosolv® SMCC HD 90, Prosolv* SMCC 50®, Starch 1500® and magnesium stearate). The study presents results of thermal analysis of the mixtures with theophylline before and after 6 months storage of the tablets at various temperatures and relative humidity conditions (25 ± 2°C/40 ± 5% RH, 40 ± 2°C/75 ± 5% RH). It was shown that high concentration of Starch 1500® (49%) affects the stability of the theophylline tablets with Prosolv® SMCC. Prosolv® SMCC had no effect on API stability as confirmed by the differential scanning calorimetry (DSC). Changes in peak placements were observed just after tabletting process, which might indicate that compression accelerated the incompatibilities between theophylline and Starch 1500. TGA analysis showed loss in tablets mass equal to water content in starch. GC-MS study established no chemical decomposition of theophylline. We demonstrated that high content of Starch 1500® (49%) in the tablet mass, affects stability on tablets containing theophylline and Prosolv® SMCC.