Standard Operating Procedure for Assay of Active Ingredient in Creams
1) Purpose
The purpose of this SOP is to outline the procedures for accurately determining the concentration of the active ingredient in creams to ensure product quality and compliance with regulatory standards.
2) Scope
This SOP applies to all personnel involved in the quality control testing of creams, including laboratory technicians, analytical chemists, and quality assurance (QA) personnel. It covers procedures for sample preparation, assay execution, and documentation.
3) Responsibilities
It is the responsibility of laboratory technicians to prepare and analyze samples, analytical chemists to develop and validate the assay method, and QA personnel to review and approve the assay results.
4) Procedure
4.1 Preparation for Assay
4.1.1 Review the batch record and sampling plan to determine the number of samples to be analyzed.
4.1.2 Ensure all assay equipment (e.g., HPLC, UV-Vis spectrophotometer) is calibrated and in proper working condition.
4.1.3 Prepare all necessary reagents, solvents, and standard solutions according to the validated method.
4.1.4 Label all sample containers and assay tubes with the necessary information, including sample ID, batch number, and date of preparation.
4.1.5 Wear appropriate personal protective equipment (PPE) such as gloves, lab coat, and safety glasses to avoid contamination.
4.2 Sample Preparation
4.2.1 Weigh an appropriate amount of cream sample into a clean container, as specified in the validated assay method.
4.2.2 Dissolve the cream sample in a suitable solvent, ensuring complete dissolution of the active ingredient.
4.2.3 Filter the solution to remove any insoluble excipients or particulates, if necessary.
4.2.4 Dilute the filtered solution to the desired concentration using a calibrated volumetric flask.
4.2.5 Prepare a blank solution and standard solutions for calibration, following the same procedure as for the sample.
4.3 Assay Execution
4.3.1 Set up the analytical instrument (e.g., HPLC, UV-Vis spectrophotometer) according to the validated method parameters.
4.3.2 Inject or place the prepared sample solution into the instrument for analysis.
4.3.3 Run the analysis according to the validated method, ensuring the system suitability criteria are met.
4.3.4 Record the peak area or absorbance of the active ingredient in the sample and compare it to the calibration curve generated from the standard solutions.
4.3.5 Calculate the concentration of the active ingredient in the cream sample using the calibration curve and appropriate formulae.
4.4 Quality Control
4.4.1 Perform the assay in duplicate or triplicate to ensure accuracy and precision.
4.4.2 Include quality control (QC) samples and reference standards in the assay run to verify the reliability of the results.
4.4.3 Compare the assay results with the specification limits to determine if the batch meets the required criteria for the active ingredient concentration.
4.5 Documentation and Review
4.5.1 Document all details of the assay procedure, including sample preparation, instrument settings, and calculation of results, in the assay log or laboratory notebook.
4.5.2 Review the assay data and ensure all results are within the specified acceptance criteria.
4.5.3 Submit the assay results for review and approval by QA personnel.
4.5.4 Maintain records of the assay results according to company policy and regulatory requirements for future reference and audits.
5) Abbreviations, if any
QA: Quality Assurance
PPE: Personal Protective Equipment
HPLC: High-Performance Liquid Chromatography
SOP: Standard Operating Procedure
6) Documents, if any
Batch Records
Sampling Plan
Assay Log
Calibration Curve Documentation
7) Reference, if any
ICH Q2(R1): Validation of Analytical Procedures: Text and Methodology
USP (United States Pharmacopeia) General Chapter on Assay and Tests
8) SOP Version
Version 1.0
