Improving the Effectiveness of the Conical Screen Mill as a Dry-Coating Process at Lab and Manufacturing Scale

Area of Science:

• Pharmaceutical Technology
• Materials Science
• Chemical Engineering

Background:

• Conical screen mills (comills) are utilized in pharmaceutical manufacturing.
• Improving powder properties like flowability and bulk density is crucial for drug formulation.
• Current methods for powder enhancement may have limitations in efficiency and scalability.

Purpose of the Study:

• To investigate the conical screen mill (comill) as an effective dry-coating process.
• To enhance the flowability and bulk density of pharmaceutical powders.
• To compare the efficacy of modified screens versus a multi-pass approach.

Main Methods:

• Utilized modified screens with reduced open area in a lab-scale comill.
• Employed Avicel PH 105 (microcrystalline cellulose) as a model cohesive powder.
• Evaluated scalability using a manufacturing scale model and compared with the multi-pass method.

Main Results:

• Modified screens increased mean residence time, significantly improving flowability and bulk density.
• The modified screen approach proved superior to the multi-pass method.
• Dry-coating with the modified comill demonstrated effectiveness and scalability.

Conclusions:

• Modified screens optimize comill performance for dry-coating applications.
• This enhanced comill process offers a practical and readily implementable solution for pharmaceutical powder improvement.
• The study validates the comill as a valuable tool for pharmaceutical dry-coating.