RESUMO
Pharmacological research is strongly driven by maximizing the bioavailability of new pharmaceuticals. For orally applied drugs the bioavailability highly depends on the process of dissolution in the gastrointestinal tract and is affected by numerous physiological and environmental factors. Available techniques for in vivo monitoring of the dissolution process are very limited and not applicable for large studies. The technique of magnetic marker monitoring provides new prospects for these investigations. However, it is currently limited due to low fields common magnetic markers produce. Hence, only highly sensitive sensors are applicable. In this paper, we performed dissolution tests of novel markers in a physical phantom with magnetoresistive sensors in an unshielded environment. The markers were continuously localized and the movement through the phantom was tracked. By analyzing the changing magnetic moment of the markers we were able to monitor the progress of dissolution in the phantom. We conclude that our proposed phantom and tracking technique is an important step towards new systems for in vivo monitoring of pharmaceutical dissolution processes.
Assuntos
Biomimética/instrumentação , Líquidos Corporais/química , Avaliação Pré-Clínica de Medicamentos/instrumentação , Magnetismo/instrumentação , Comprimidos/análise , Comprimidos/química , TransdutoresRESUMO
A 21-yr-old Caucasian man developed accelerated irreversible dense bilateral cataracts 4 wk after control of his newly diagnosed insulin-dependent diabetes mellitus (IDDM) and 12 wk after the onset of his symptoms. Although transitory cataracts have been identified in patients with newly diagnosed IDDM, there is no mention in the literature of irreversible cataract formation this soon after diagnosis (see ref. 1).
