Suspensions are one of the most important dosage forms under liquid orals. A large number of drugs are formulated as suspensions considering their therapeutic and commercial benefits. The aim of the present study is to formulate paracetamol suspensions employing Plantago ovata mucilage as a suspending agent and evaluate the sedimentation stability using near infrared transmission measurements. The mucilage extracted from Plantago ovata seeds is a natural suspending agent that can be used as an effective alternative for traditional suspending agents. Paracetamol suspensions were formulated using mucilage of Plantago ovata (POM) as suspending agent at different concentrations (0.25, 0.5, 0.75 and 1.0 %) and their infrared extinction profiles were compared to determine the corresponding sedimentation stability. The infrared (IR) spectroscopy and thermal analysis by differential scanning calorimetry (DSC), shows compatibility between paracetamol and POM, as there is no significant interaction. Physical stability of paracetamol suspensions was studied in terms of sedimenation stability employing infrared extinction profiles by using the instrument Separation analyzer (LUMiReader®). The LUMiReader® instantaneously measures the extinction profiles of the transmitted light across the entire length of a suspension sample employing STEP-Technology (Space- and Time-resolved Extinction Profiles Technology). Instability indices determined on different suspension formulations indicated that POM at 0.25% is a suitable and preferable suspending agent for the preparation of stable suspensions of paracetamol.
