Standard Operating Procedure for pH Determination

1) Purpose

This SOP outlines the procedures for determining the pH of pharmaceutical raw materials and products.

2) Scope

This SOP applies to pH determination of raw materials, intermediate products, and finished pharmaceutical products in the manufacturing facility.

3) Responsibilities

The Quality Control (QC) department is responsible for performing pH determination. Production personnel are responsible for sample preparation. Quality Assurance (QA) oversees the process and ensures compliance with this SOP and regulatory requirements.

4) Procedure

4.1 Preparation

1. Review the pH determination protocol and ensure all necessary materials and equipment are available (e.g., pH meter, calibration solutions).
2. Verify the calibration and functionality of the pH meter.

4.2 Sample Collection and Preparation

1. Collect representative samples of raw materials or products according to sampling procedures.
2. Prepare the samples by ensuring they are properly dissolved or dispersed in suitable solvent or medium.
3. Allow the samples to equilibrate to room temperature if required.

4.3 Testing Procedure

1. Calibrate the pH meter using standard buffer solutions covering the expected pH range of the samples.
2. Insert the electrode into the sample solution and record the pH reading once stable.
3. Rinse the electrode between measurements with suitable solvent and recalibrate if necessary.
4. Perform pH determination in duplicate or as per protocol requirements.

4.4 Acceptance Criteria

1. Ensure that the pH values of the tested samples meet the specified acceptance criteria based on compendial standards or product specifications.
2. Document any deviations from acceptance criteria and investigate root causes if necessary.

4.5 Reporting and Documentation

1. Document all testing activities, including results and any deviations, in the appropriate logbooks and records.
2. Prepare a pH determination report summarizing the findings for each batch tested.
3. Review and approve the testing report to ensure accuracy and compliance with regulatory requirements.

5) Abbreviations, if any

SOP: Standard Operating Procedure
QC: Quality Control
QA: Quality Assurance

6) Documents, if any

pH Determination Protocol, Testing Records, Testing Reports, Sample Collection and Preparation Records

7) Reference, if any

Regulatory guidelines such as USP <791> pH, European Pharmacopoeia (Ph. Eur.) 2.2.3 pH Measurement

8) SOP Version

Version 1.0