Procedure for Loss on Drying Testing
1) Purpose
The purpose of this SOP is to outline the procedure for determining the loss on drying of pharmaceutical substances using appropriate analytical techniques.
2) Scope
This SOP applies to all pharmaceutical substances within the facility that require loss on drying testing as part of quality control, following pharmacopeial guidelines and internal specifications.
3) Responsibilities
Quality Control (QC) Department: Responsible for performing loss on drying testing and ensuring compliance with this SOP.
Analytical Laboratory: Responsible for conducting analysis using suitable techniques and interpreting results accurately.
4) Procedure
4.1 Instrument Setup:
4.1.1 Ensure the moisture balance or drying oven is calibrated according to manufacturer instructions and method validation protocols.
4.1.2 Verify the cleanliness and condition of the drying chamber or balance pan.
4.1.3 Stabilize the instrument at the specified temperature and operating conditions for accurate measurements.
4.2 Sample Preparation:
4.2.1 Obtain representative samples of pharmaceutical substances requiring loss on drying testing.
4.2.2 Label samples with batch numbers, dates, and any other relevant information.
4.2.3 Ensure samples are weighed accurately and placed in suitable containers for drying.
4.3 Drying Procedure:
4.3.1 Place the sample in the moisture balance or drying oven and start the drying process.
4.3.2 Dry the sample until a constant weight is achieved, indicating no further moisture loss.
4.3.3 Record the initial and final weights of the sample after drying.
4.4 Calculation:
4.4.1 Calculate the loss on drying using the formula: Loss on Drying (%) = [(Initial Weight – Final Weight) / Initial Weight] × 100.
4.4.2 Perform calculations based on the average of triplicate measurements to ensure accuracy.
4.4.3 Record all calculations and ensure data integrity throughout the process.
4.5 Documentation:
4.5.1 Prepare a Loss on Drying Testing Report summarizing the sample details, testing methods, results, and conclusions.
4.5.2 Include all relevant data, calculations, and statistical analyses in the report.
4.5.3 Review and approve the report by QC Manager before release.
5) Abbreviations, if any
QC: Quality Control
6) Documents, if any
Loss on Drying Testing Report
Method Validation Protocol and Report
Instrument Calibration Records
7) Reference, if any
USP General Chapter <731> – Loss on Drying
Pharmacopeial standards for loss on drying testing in pharmaceutical substances
8) SOP Version
Version 1.0
