Procedure for Ash Content Determination

1) Purpose

The purpose of this SOP is to outline the procedure for determining the ash content of pharmaceutical substances using appropriate analytical techniques.

2) Scope

This SOP applies to all pharmaceutical substances within the facility that require ash content determination as part of quality control, following pharmacopeial guidelines and internal specifications.

3) Responsibilities

Quality Control (QC) Department: Responsible for performing ash content determination and ensuring compliance with this SOP.
Analytical Laboratory: Responsible for conducting analysis using suitable techniques and interpreting results accurately.

4) Procedure

4.1 Apparatus Setup:
    4.1.1 Ensure the muffle furnace or ashing oven is calibrated according to manufacturer instructions and method validation protocols.
    4.1.2 Verify the cleanliness and condition of crucibles and other apparatus.
    4.1.3 Stabilize the furnace at the specified temperature for ashing.

4.2 Sample Preparation:
    4.2.1 Obtain representative samples of pharmaceutical substances requiring ash content determination.
    4.2.2 Label samples with batch numbers, dates, and any other relevant information.
    4.2.3 Accurately weigh samples into pre-ignited crucibles.

4.3 Ashing Procedure:
    4.3.1 Place crucibles with samples in the muffle furnace or ashing oven.
    4.3.2 Ash the samples at a specified temperature for a defined period until complete combustion.
    4.3.3 Cool the crucibles in a desiccator and weigh them after ashing.

4.4 Calculation:
    4.4.1 Calculate the ash content using the formula: Ash Content (%) = [(Weight of Ash / Initial Weight of Sample)] × 100.
    4.4.2 Perform calculations based on 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 an Ash Content Determination 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

Ash Content Determination Report
Method Validation Protocol and Report
Instrument Calibration Records

7) Reference, if any

USP General Chapter <281> – Residue on Ignition
Pharmacopeial standards for ash content determination in pharmaceutical substances

8) SOP Version

Version 1.0