Standard Operating Procedure for Use of Antioxidants in Lyophilized Formulations

1) Purpose

This SOP outlines the process for incorporating antioxidants into lyophilized formulations to prevent oxidative degradation of the active ingredients during processing and storage.

2) Scope

This SOP applies to formulation scientists, production operators, and QA personnel involved in the preparation of lyophilized products requiring antioxidants for stabilization.

3) Responsibilities

• Formulation Scientists: Responsible for selecting appropriate antioxidants based on the formulation requirements.
• Operators: Responsible for incorporating antioxidants into the formulation as outlined in the Batch Manufacturing Record (BMR).
• QA: Responsible for verifying the antioxidant incorporation and ensuring accurate documentation.

4) Procedure

4.1 Selection of Antioxidants

4.1.1 Criteria for Selection

• 4.1.1.1 Antioxidants must be non-toxic and compatible with the formulation. Commonly used antioxidants include ascorbic acid, tocopherols, and butylated hydroxytoluene (BHT).

4.2 Incorporation of Antioxidants

4.2.1 Weighing and Dispensing

• 4.2.1.1 Weigh the antioxidants using a calibrated balance as specified in the BMR.
• 4.2.1.2 Add the antioxidants to the formulation solution during preparation and stir until fully dissolved.

4.2.2 Mixing and Homogenization

• 4.2.2.1 Stir the solution using a mechanical stirrer to ensure the antioxidants are evenly distributed throughout the solution.
• 4.2.2.2 Homogenize the mixture if necessary to ensure uniformity.

4.3 Filtration and Filling

• 4.3.1 Filter the formulation using a sterile 0.22-micron