intermediates, and APIs.

3. Responsibilities

• QC Analyst: Prepare and standardize solutions as per the procedure.
• QC Reviewer: Verify calculations, labels, and log entries.
• QA Officer: Ensure compliance with this SOP during audits and reviews.

4. Accountability

The QC Head is accountable for ensuring accurate preparation, traceability, and proper documentation of all volumetric solutions.

5. Procedure

5.1 General Instructions

1. Use only AR/GR grade chemicals and Class A volumetric glassware.
2. Record all preparation and standardization data in the Volumetric Solution Preparation Log (Annexure-1).
3. Label each solution with:
   • Name of solution
   • Normality or Molarity
   • Date of preparation
   • Prepared by
   • Standardized by
   • Standardization factor
   • Expiry date

5.2 Preparation of Volumetric Solutions

1. Weigh the required amount of substance using a calibrated analytical balance.
2. Dissolve the substance in purified water in a beaker using a glass rod.
3. Transfer the solution quantitatively into a volumetric flask and make up to the mark.
4. Mix thoroughly and label the flask appropriately.

5.3 Standardization

1. Standardize all volumetric solutions against primary standards (e.g., sodium carbonate, potassium hydrogen phthalate).
2. Perform at least three concordant titrations with RSD ≤ 1.0%.
3. Calculate factor using the formula:
   Factor = (Weight of standard × 1000) / (Volume of titrant used × Equivalent weight of standard)
4. Document factor and average value in the standardization section of the logbook.
5. Apply correction factor during assay calculation where necessary.

5.4 Re-standardization and Expiry

1. Re-standardize aqueous volumetric solutions weekly and non-aqueous solutions monthly unless specified otherwise.
2. Expiry for:
   • Aqueous solutions: 7 days
   • Non-aqueous solutions: 30 days
3. If any deviation in factor is observed, reject the solution and prepare afresh.

5.5 Storage and Usage

1. Store solutions in clean, labeled amber or colorless bottles depending on light sensitivity.
2. Tightly cap and store at room temperature or as per chemical requirement.
3. Record issuance and usage in the Solution Usage Register (Annexure-2).

6. Abbreviations

• AR: Analytical Reagent
• GR: Guaranteed Reagent
• QC: Quality Control
• RSD: Relative Standard Deviation
• SOP: Standard Operating Procedure

7. Documents

1. Volumetric Solution Preparation Log (Annexure-1)
2. Solution Usage Register (Annexure-2)
3. Standardization Records

8. References

• ICH Q2(R1) – Validation of Analytical Procedures
• USP General Chapters <851> and <941>
• 21 CFR Part 211

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Volumetric Solution Preparation Log

Date	Solution Name	Normality	Prepared By	Factor	Expiry	Remarks
13/04/2025	0.1N HCl	0.100	Sunita Reddy	0.999	20/04/2025	Clear solution

Annexure-2: Solution Usage Register

Date	Solution Used	Test	Batch No.	Used By	Remarks
14/04/2025	0.1N HCl	Assay	API-20250413	Ravi Kumar	Used within expiry

Revision History:

Revision Date	Revision No.	Details	Reason	Approved By
01/01/2022	1.0	Initial Version	GMP Compliance	QA Head
13/04/2025	2.0	Updated standardization procedure and expiry timelines	Audit Suggestion	QA Head