Standard Operating Procedure for Assay of Active Pharmaceutical Ingredient (API) by HPLC in Elixirs
| Department | Elixir Department |
|---|---|
| SOP No. | SOP/ELX/212/2025 |
| Supersedes | SOP/ELX/212/2022 |
| Page No. | Page 1 of 10 |
| Issue Date | 11/04/2025 |
| Effective Date | 15/04/2025 |
| Review Date | 11/04/2026 |
1. Purpose
To describe the procedure for performing quantitative analysis of the Active Pharmaceutical Ingredient (API) in elixir formulations using High-Performance Liquid Chromatography (HPLC), ensuring accuracy, precision, and compliance with pharmacopeial or validated methods.
2. Scope
This SOP applies to the Quality Control (QC) Department responsible for testing elixir samples for API content using HPLC instrumentation as per standard or in-house validated methods.
3. Responsibilities
- QC Analyst:
- Prepare samples and standards, operate HPLC, record and interpret results.
- QC Supervisor:
- Review chromatograms and calculations for accuracy.
- QA Officer:
- Verify compliance with method and documentation.
4. Accountability
The QC Head is accountable for the execution and validity of HPLC assay results. QA Head is responsible for verifying that all assay data complies with GMP requirements.
5. Procedure
5.1 Preparation for
- Review the current pharmacopeial monograph or validated in-house method for assay conditions.
- Ensure HPLC instrument calibration is within due date.
- Clean and check the system – purge mobile phase lines and equilibrate the column.
- Prepare mobile phase as per method, filter through 0.45 µm filter, and degas.
5.2 Preparation of Standard Solution
- Weigh the specified quantity of working standard (e.g., 100 mg) and transfer to a 100 mL volumetric flask.
- Dissolve in suitable solvent (e.g., methanol, water) and dilute to volume.
- Filter through 0.45 µm syringe filter and transfer to labeled HPLC vial.
5.3 Preparation of Sample Solution
- Shake the elixir sample to ensure uniformity.
- Transfer the required volume (e.g., 10 mL) into a volumetric flask, dilute as per method, and sonicate if needed.
- Filter and transfer the clear solution to an HPLC vial for injection.
5.4 HPLC Conditions (Example Method)
- Column: C18, 250 mm × 4.6 mm, 5 µm
- Mobile Phase: Methanol:Water (60:40 v/v)
- Flow Rate: 1.0 mL/min
- Detection Wavelength: 254 nm
- Injection Volume: 20 µL
- Run Time: As per method (typically 10 min)
5.5 Analysis and Calculation
- Inject standard and sample solutions into the HPLC system.
- Record retention time and area under curve (AUC) for main API peak.
- Calculate API content using the formula:
API (%) = (Sample Area × Std Concentration × Dilution Factor × 100) / (Standard Area × Sample Concentration)
5.6 System Suitability and Acceptance Criteria
- Check system suitability parameters:
- Theoretical Plates: ≥ 2000
- Tailing Factor: ≤ 2.0
- RSD of replicate injections (n=6): ≤ 2.0%
- API content must be within 90.0%–110.0% of label claim (or as per specification).
5.7 Documentation
- Record sample preparation, instrument conditions, and results in the HPLC Assay Logbook (Annexure-1).
- Attach chromatograms, calculations, and method reference to the BMR.
6. Abbreviations
- SOP: Standard Operating Procedure
- QA: Quality Assurance
- QC: Quality Control
- HPLC: High Performance Liquid Chromatography
- API: Active Pharmaceutical Ingredient
- BMR: Batch Manufacturing Record
7. Documents
- HPLC Assay Logbook (Annexure-1)
- Batch Manufacturing Record (BMR)
- Instrument Calibration Records
8. References
- USP General Chapter <621> – Chromatography
- ICH Q2(R1) – Validation of Analytical Procedures
- 21 CFR Part 211.165 – Testing and Release for Distribution
9. SOP Version
Version: 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: HPLC Assay Logbook
| Date | Batch No. | Sample ID | Retention Time | Area | API Content (%) | Tested By | Checked By |
|---|---|---|---|---|---|---|---|
| 11/04/2025 | ELX-0425-030 | API-A | 5.36 | 120345 | 99.2% | Rajesh Kumar | Sunita Reddy |
Revision History:
| Revision Date | Revision No. | Revision Details | Reason for Revision | Approved By |
|---|---|---|---|---|
| 01/01/2024 | 1.0 | Initial Release | New SOP | QA Head |
| 11/04/2025 | 2.0 | Updated with CAPA linkage and new system suitability criteria | GMP Enhancement | QA Head |