Assessment of tableting properties using infinitesimal quantities of powder medicine II

Static compression tests were carried out using a new compression machine named the Micro Powder Characterizer. It requires infinitesimal quantities of samples in order to estimate the tableting properties (compressibility and tableting problems, e.g. capping, sticking and so on) of new drug candidates in the early stage of development. A total of six kinds of samples containing aspirin and ascorbic acid were used as model drugs. The estimation of compressibility was mainly performed by analysis of stress displacement curves and measurements of tensile strength. The tableting problems were predicted from maximum ejection stress and ejection energy. It was found from this study that it was possible to estimate the tableting property of the samples using the new compression machine. The Micro Powder Characterizer enables the tableting properties of pharmaceutical powders to be determined using approximately 10 mg per measurement, which indicates that appropriate tablet formulation studies of drug candidate might be promising in the early development stage.