Iron is one of the most important elements in our body and its deficiency leads to the most common type of anemia, known as iron deficiency anemia. While oral iron supplementation is the safest, most efficient and cost-effective intervention, it often leads to gastrointestinal side effects such as vomiting, diarrhoea, heartburn and abdominal pain, which can contribute to poor patient compliance. If the patient does not respond to oral treatment or in certain medical conditions, parenteral administration can be used as an alternative. As oral dosage forms with a sustained iron release profile are associated with fewer adverse effects, many studies have focussed on developing new technological approaches to achieve the desired iron release profile. In this master thesis, we aimed to utilise the process of (micro)encapsulation to achieve a prolonged release of the water-soluble form of iron (i.e. Fe-gluconate). For this purpose, the (co-)extrusion of a lamellar liquid jet with a vibrating nozzle technology (in combination with the ionotropic gelation process) was used in addition to the coacervation method, direct adsorption on mesoporous carriers and the emulsion-based wet granulation process. Our primary objective was to produce a solid (powdered) formulation with a high content of water-soluble Fe-gluconate and with a modified release of the encapsulated compound. The iron content and release profiles of the manufactured products were evaluated in acidic (pH=1,2) and neutral (pH=6,8) media. For comparison, counterparts with poorly water-soluble Fe-pyrophosphate were prepared for some formulations. The iron concentration in the prepared samples was determined spectrophotometrically by observing the formation of a coloured complex with 1,10–phenantroline at a specific wavelength. While the vibrating nozzle technology was most effective in slowing down the release of the water-soluble Fe-gluconate, we were unable to prolong the release using the direct adsorption technique based on the mesoporous carrier Syloid® 244 FP. Contrary to our expectations, coacervates also failed to release Fe-gluconate over a longer period of time, while its release was slightly slowed down from granules prepared using the emulsion-based wet granulation method. However, there are other options that could be tested in the future to improve and optimise the technological approaches to achieve the desired release profile.
|