Standard Operating Procedure for Incorporation of Preservatives in Lyophilized Formulations

1) Purpose

This SOP describes the process of incorporating preservatives into lyophilized formulations to ensure product stability and sterility during storage and usage.

2) Scope

This SOP applies to all personnel involved in the preparation of formulations that require preservatives for lyophilization, including formulation scientists and operators.

3) Responsibilities

• Formulation Scientists: Responsible for selecting appropriate preservatives.
• Operators: Responsible for incorporating the preservative according to the Batch Manufacturing Record (BMR).
• QA: Responsible for verifying the preservative addition and documentation.

4) Procedure

4.1 Selection of Preservatives

4.1.1 Criteria for Selection

• 4.1.1.1 Preservatives must be non-toxic, effective in low concentrations, and compatible with the formulation and lyophilization process.
• 4.1.1.2 Commonly used preservatives include benzyl alcohol, phenol, and parabens.

4.2 Incorporation of Preservatives

4.2.1 Weighing and Dispensing

• 4.2.1.1 Weigh the preservative using a calibrated balance as specified in the BMR.
• 4.2.1.2 Dispense the preservative into the solution while stirring gently to ensure uniform distribution.

4.2.2 Homogenization

• 4.2.2.1 Mix the preservative with the formulation using a mechanical stirrer to ensure uniformity.

4.3 Documentation

All steps, including the preservative’s weight and batch number, must be recorded in the Preservative Addition Logbook and verified by QA.

5) Abbreviations

• BMR: Batch Manufacturing Record

6) Documents

• Preservative Addition Logbook

7) References

• Pharmacopoeial guidelines on preservatives