A novel method for estimating solid fraction of roller-compacted ribbons

Area of Science:

• Pharmaceutical Sciences
• Materials Science
• Chemical Engineering

Background:

• Roller compaction is a key process in pharmaceutical manufacturing for producing granules and compacts.
• Accurate determination of solid fraction (relative density) is crucial for controlling product quality and performance.
• Traditional methods like dimensional measurement can be challenging for certain formulations.

Purpose of the Study:

• To develop a simple, weight-based method for estimating the solid fraction of roller compacted ribbons.
• To provide an alternative to dimensional measurements, particularly for challenging formulations.
• To incorporate surface texture and ribbon relaxation into the mathematical model for improved accuracy.

Main Methods:

• A novel mathematical model was developed to estimate solid fraction using the weight of produced ribbons.
• The model incorporates surface texture of compaction rolls and a correction factor for ribbon relaxation.
• Ribbon relaxation was estimated based on roll geometry, roll gap, and ribbon thickness.

Main Results:

• The weight-based method provided solid fraction estimates comparable to traditional caliper measurements.
• Inclusion of ribbon relaxation significantly reduced the error sum of squares (SSE) for microcrystalline cellulose/dicalcium phosphate and microcrystalline cellulose/lactose monohydrate formulations.
• The SSE decreased by four-fold and twelve-fold, respectively, demonstrating the model's improved accuracy with relaxation correction.

Conclusions:

• The proposed weight-based method is a viable and accurate alternative for estimating the solid fraction of roller compacted ribbons.
• Accounting for ribbon relaxation is essential for precise solid fraction determination, especially for specific pharmaceutical formulations.
• This throughput method offers practical utility for quality control in pharmaceutical manufacturing.