Twin screw granulation as a simple and efficient tool for continuous wet granulation

Area of Science:

• Pharmaceutical Technology
• Chemical Engineering
• Materials Science

Background:

• Continuous manufacturing is increasingly important in pharmaceutical production.
• Traditional wet granulation often requires multiple steps, including wet sieving.
• Twin screw extrusion offers potential for integrated granulation processes.

Purpose of the Study:

• To investigate the modification of a twin screw extruder for continuous wet granulation.
• To evaluate the robustness and reproducibility of twin screw granulation for alpha-lactose monohydrate.
• To assess the impact of processing parameters and formulation variables on granule and tablet properties.

Main Methods:

• Modified a twin screw extruder setup and screw design for continuous wet granulation.
• Studied the influence of screw speed, input rate, and water concentration on granulation.
• Evaluated granule properties, tablet characteristics (tensile strength, friability, disintegration), and drug dissolution.
• Assessed process reproducibility over an 8-hour production period.

Main Results:

• Continuous wet granulation of alpha-lactose monohydrate was achieved without wet sieving.
• Optimal water concentration ranged from 5.5-8.5% for feasible granulation and good granule properties.
• PVP addition significantly impacted tablet properties, with 2.5% PVP yielding tablets of high tensile strength and low friability.
• Tablets containing hydrochlorothiazide met dissolution requirements.
• Process reproducibility was confirmed over 8 hours of continuous operation.

Conclusions:

• Modified twin screw extrusion is an effective and robust method for continuous wet granulation.
• The process allows for the production of high-quality granules and tablets with reproducible characteristics.
• Twin screw granulation presents an efficient alternative to conventional granulation techniques in pharmaceutical manufacturing.