Another common pellitization technique employed by Vision Pharmaceutical is layering technique. This production technique is predominantly used for taste masked and control release formulations. This technique is of two types, solution layering and powder layering.
In solution layering powder feed material and other components are dissolved in solvent. Then this solution or suspension is sprayed on the starter core and spread evenly on the surface. Spraying is followed by drying phase, in this phase dissolved material get crystallized and solid bridges are formed between drug and polymers. Vision Pharmaceutical controls drying method very strictly because drying can affect structural and functional properties of pellets. Various techniques are employed by Vision Pharmaceutical’s production unit to increase dissolution properties of pellets.
In powder layering the seeds are charged into the pellitizer and on its surface. Then the binder liquid and powder feed material is sprayed tangentially. The uniform distribution of powder over the seed surface is ensured by rolling movement confirming its spherical shape. It involves uniform deposition of fine drug particles plus excipients on the surface of starting core with the help of binding liquid.
Vision Pharmaceutical never use conventional coating pan ( used by many pellet’s manufacturers even today) due to its limitations, like poor degree of mixing and very inefficient drying. We employ procedures that deliver the powder in such a manner and rate that is in equilibrium with the binder liquid application rate throughout the process. We at Vision make sure that no over wetting and dust generation occur as it will reduce the overall quality and yield of products.
Fluidized Bed Processor:
Also called Wurster process, it performs multiple function like coating, drying, granulations and pellitization. Vision Pharmaceutical prepares control release formulations by this technique particularly.
It involves successive deposition of several layers of the coating material. A spray nozzle is fitted in the base plate with concurrent air flow and pressurised stream of specific spray pattern. The particles are accelerated within the Wruster tube and coating material is continuosly sprayed through the spray case. The process continues till appropriate build up on the surface of particles takes place.
Vision Pharmaceutical controls critical parameters in order to avoid powder adherence to side of hopper and if the bed temperature is high and there is a risk of powder lost to exhaust system, binders are consistently used during solution Layering to impart strenght to the pellets.
Our Quality Control parameter ensured that our consumers get best form of sustained released, and taste masked drug pellets.