Stability Testing of Amoxicillin Nano-suspension as Promising Tool for Drug Delivery System

While nano-suspension amoxicillin is one of the approaches for improving dissolution rate of amoxicillinan antibiotic used widely. Stabilizing these nanodosage forms is always a challenge. The present study utilizes nanoprecipitation solvent evaporation technique for preparation of amoxicillin nanoparticles andproposed stability study approach of the same. The methodology was based on investigating stability of amoxicillin nano suspension in vitro, the optimized drug(polymer ratio re-formulated into nano-suspensions) and we compared our results with marketed suspensions. Samples were initially characterized and then subjected to stability testing at ambient temperature and relative humidity up to 6 months assayed using a validated HPLC method. During initial characterization, increase in saturation solubility and dissolution rate observed in all samples. During stability testing, there was gradual decrease in saturation solubility and dissolution rate of the samples, over the period of 3 months. This study considers long-term isothermal measurements, consistent with short-term non-isothermal (accelerating) measurements, providing predictive model to calculate the isothermal degradation periods. As per our results, we agree with the possibility to calculate the value of kinetic constants based on a fixed degradation limit, regardless of the shape of the curve. The accuracy of the prediction would be assessed by comparison of estimated shelf life versus data coming from traditional stability studies.