Browsing by Subject "jatkuvatoiminen lääkevalmistus"

Background: Continuous manufacturing has been utilized for decades in many industries since it has many advantages compared to batch manufacturing. Therefore the interest towards continuous processes has arisen also in the pharmaceutical industry. Also, the strict regulations characteristic of pharma industry have started to change more favorable towards continuous manufacturing when the possibilities of continuous processes to produce higher quality products faster and more efficiently, have been proven in many researches. Objectives: Objectives of this thesis were to clarify the effect of the material characteristics on material flowability from continuous feeders and to study how different toolings, like feeding screws, affect the feeding of materials with different characteristics. Based on these results, a possibility to model the feeding results of a material based on only some measured material characteristics was also under investigation. The aim was to develop a clear and systematic procedure which would simplify the determination of the most suitable equipment when starting to feed a new material. Methods: The similarity of flowability of various pharmaceutical powders from continuous feeders was studied. First material characteristics affecting material flowability from a feeder based on literature was determined from 26 pharmaceutical powders. Following this, six materials were chosen to be studied with gravimetric powder feeders using different kinds of research frames. The six materials formed three material pairs, in which two materials had clear similarities in the flowability characteristics. The reason for this was that the flowability from feeders with similar materials could be compared. The feeding of materials was determined investigating the feed rate capacity and accuracy of feed rate of material. Also, the effect of feeder screws and the speed of the screws on the feeding capability of a material was investigated. A model to predict the feeding result based on material characteristics was built using PLSand MLR-methods. Results: The prediction of material feeding was not possible with PLS- and MLR-modeling methods. The feeding of similar materials was wound to be alike. Poor flow characteristics correlated with poor feeding results. PCA- and cluster analysis were found suitable to define the similarity of materials. Conclusions: The success of feeding of pharmaceutical powders is clearly affected by the material flowability properties. The feeding screws and screw speed affect the feeding accuracy, too. The prediction of feeding results of specific material, would need much more data to produce valid and trustworthy models. However, it seems highly possible to be able to build a model with more materials.