use of the standards in testing.

5. Procedure

5.1 Standard Selection

1. Select the appropriate analytical standard based on the testing requirements (e.g., reference substance, working standard, or calibration standard).
2. Verify that the standard is sourced from an authorized and reputable supplier or produced in-house following established procedures.
3. Check the expiration date and ensure that the standard has been stored and handled correctly according to storage guidelines (e.g., temperature, humidity, light exposure).

5.2 Preparation of Analytical Standard

1. Weigh the appropriate quantity of the analytical standard using an analytical balance, ensuring accuracy within the specified tolerance limits.
2. Dissolve the standard in an appropriate solvent (e.g., water, methanol, acetonitrile) according to the method specified in the batch record or pharmacopeial guidelines.
3. If necessary, filter the solution to remove any insoluble particles or impurities that may interfere with testing.
4. Prepare a series of dilutions or standard solutions as required by the analytical method (e.g., calibration curve, assay, content uniformity testing).

5.3 Verification and Calibration

1. Verify the concentration of the prepared standard solution by comparing the measured value to the known concentration using an appropriate analytical method, such as HPLC, UV-Vis spectroscopy, or titration.
2. If preparing a calibration standard, prepare a calibration curve by analyzing multiple concentrations of the standard solution to establish a relationship between concentration and response.
3. Ensure that the calibration curve has a correlation coefficient (R²) of at least 0.99, as specified in the method.

5.4 Labeling and Documentation

1. Label the prepared standard solution with the following information:
   • Standard name
   • Concentration
   • Preparation date
   • Expiration date
   • Lot/batch number
   • Storage conditions
2. Record the preparation process, including the quantities used, solvents, and any observations, in the preparation log (Annexure-1).
3. Ensure all records are signed and dated by the person responsible for the preparation and verification of the standard.

5.5 Storage and Stability

1. Store the prepared analytical standard in a labeled container, ensuring that it is stored under the specified conditions (e.g., temperature, humidity, light exposure).
2. Ensure that the standard is stored in a manner that prevents contamination or degradation (e.g., in sealed containers, away from direct light).
3. Monitor the stability of the prepared standard over time, and ensure that it is used within the specified shelf life.

5.6 Documentation and Record-Keeping

1. Document the preparation of all analytical standards in the preparation log (Annexure-1) and ensure that all records are signed, dated, and stored in accordance with the company’s record retention policy.
2. Maintain records of the verification and calibration of the standards in the calibration log (Annexure-2).
3. Ensure that all records are available for review during audits and inspections.

5.7 Quality Control Testing

1. Conduct periodic testing of the prepared standards to ensure that they maintain their integrity and meet the specified quality criteria.
2. Retest the standard if it exceeds its shelf life or if any issues are identified during routine usage.
3. Document any deviations from the acceptance criteria and take corrective actions as necessary.

6. Abbreviations

• SOP: Standard Operating Procedure
• GMP: Good Manufacturing Practice
• QC: Quality Control
• QA: Quality Assurance
• API: Active Pharmaceutical Ingredient
• HPLC: High-Performance Liquid Chromatography

7. Documents

1. Preparation Log (Annexure-1)
2. Calibration Log (Annexure-2)

8. References

• USP <811> – General Chapter on Reference Standards
• 21 CFR Part 211 – Current Good Manufacturing Practice for Finished Pharmaceuticals (US FDA)
• European Pharmacopoeia (EP) – Analytical Method Validation

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Preparation Log

Standard Name	Concentration	Preparation Date	Expiration Date	Lot/Batch Number	Storage Conditions
API Standard	100 mg/mL	01/03/2026	01/03/2027	Lot-12345	Store at 2-8°C

Annexure-2: Calibration Log

Standard Name	Calibration Method	Result	Calibration Date	Next Calibration Date
API Standard	HPLC Calibration	Pass	01/03/2026	01/03/2027

Revision History:

Revision Date	Revision No.	Revision Details	Reason for Revision	Approved By
01/01/2024	1.0	Initial Version	New SOP Creation	QA Head
01/02/2025	2.0	Updated Standard Preparation Process	Refined standards preparation procedure	QA Head