Statistical analysis of differences in the Raman spectra of polymorphs.

Raman spectroscopy is a useful tool for identifying polymorphs of pharmaceutical compounds. One limitation of the technique is that the small differences in Raman spectra require confirmation of polymorphs by other methods. Fourteen compounds, both commercial and proprietary pharmaceutical compounds and their polymorphs, were analyzed by Raman microscopy.

Improving the detection of degradants and impurities in pharmaceutical drug products by applying mass spectral and chromatographic searching.

Liquid chromatography/mass spectrometry (LC/MS) and NMR are commonly used to identify metabolites, impurities and degradation products in the pharmaceutical industry. To more efficiently deal with the large volumes of data these techniques generate, software programs have been developed by various vendors to assist in the identification of these compounds through the use of spectral and chromatographic search algorithms. The feasibility of using such programs for detecting drug degradants and impurities is assessed.

Rapid estimation of kinetic parameters for thermal decomposition of penicillins by modulated thermogravimetric analysis.

Modulated thermogravimetic analysis (MTGA) is evaluated for the rapid estimation of thermal stability using several penicillin antibiotics as model compounds. The MTGA technique utilizes an oscillatory temperature program to obtain Arrhenius kinetic parameters through a mass loss during thermal degradation. To evaluate the reliability of this technique, activation energies (E(a)), log pre-exponential factor (logZ), and log first order rate constants (logk) obtained by MTGA for the thermal decomposition of ampicillin anhydrous, ampicillin trihydrate, ampicillin sodium salt, and penicillin G potassium salt are compared to existing literature values.