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Macro-Rheology Characterization of Gill Raker Mucus in the Silver Carp, Hypophthalmichthys molitrix
Published on: July 10, 2020
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On-line rheological characterization of semi-solid formulations.
Pernille Kjærgaard Qwist1, Camilla Sander2, Fridolin Okkels3
1Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, Copenhagen, Denmark; LEO Pharma A/S, Industriparken 55, Ballerup, Denmark.
Summary
A novel Pressure Difference Apparatus (PDA) enables real-time rheological monitoring during semi-solid manufacturing. This process analytical technology (PAT) tool measures viscosity and viscoelastic properties, enhancing quality control.
Area of Science:
- Pharmaceutical Manufacturing
- Rheology
- Process Analytical Technology (PAT)
Background:
- Rheological properties are critical quality attributes for semi-solid products.
- Current Process Analytical Technology (PAT) tools for rheological measurements are not widely adopted in pharmaceutical manufacturing, often limited to viscosity measurements.
- On-line or in-line monitoring of rheological parameters is needed for effective manufacturing control strategies.
Purpose of the Study:
- To investigate an automated system, the Pressure Difference Apparatus (PDA), for on-line rheological measurements during semi-solid manufacturing.
- To develop and verify a calibration model for the PDA using hydroxyethyl cellulose gels.
- To assess the PDA's capability to monitor manufacturing changes in real-time.
Main Methods:
- Developed an automated Pressure Difference Apparatus (PDA) utilizing a topology-optimized channel and capillary viscometer.
- The PDA measures pressure difference at varying flow rates to determine viscosity, storage modulus (G'), and loss modulus (G″).
- Calibrated the PDA with hydroxyethyl cellulose gels (1.0-1.5% polymer content) and validated its performance during on-line manufacturing of a gel product.
Main Results:
- Successfully developed and verified a calibration model for the PDA.
- The PDA accurately reflected changes in viscosity and rheological properties during on-line manufacturing, correlating with product dilution.
- PDA measurements covered relevant shear rate and frequency ranges for manufacturing, complementing standard rheometer data with real-time insights.
Conclusions:
- The Pressure Difference Apparatus (PDA) is a viable on-line tool for monitoring rheological attributes in semi-solid manufacturing.
- Real-time rheological data from the PDA can be integrated into manufacturing control strategies.
- The PDA offers a complementary approach to traditional rheometry, providing valuable process insights during production.
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