intended application.

2. Scope

This SOP is applicable to all new or modified methods developed in the Analytical Method Development (AMD) department of pharmaceutical API and formulation units. It includes selection from techniques such as UV, HPLC, GC, FTIR, potentiometry, and titrimetry.

3. Responsibilities

• Analytical Chemist: Conducts literature review, selects technique, and documents justification.
• Method Development Scientist: Approves the selection based on preformulation data and validation feasibility.
• QA Officer: Reviews the selection rationale and supporting documentation for regulatory compliance.

4. Accountability

The Head of AMD Department is accountable for ensuring all technique selections are justified, scientifically sound, and aligned with ICH Q2(R1), USP, and other pharmacopeial requirements.

5. Procedure

5.1 Preliminary Assessment

1. Obtain product-specific information:
   • Physicochemical characteristics (solubility, pKa, UV absorbance, volatility)
   • Therapeutic concentration range
   • Formulation matrix (excipients, solvents)
2. Review available pharmacopoeial monographs or prior validated methods.

5.2 Technique Selection Matrix

Use the following criteria to select the most appropriate analytical technique:

Technique	Ideal For	Limitations
HPLC	Non-volatile, polar compounds	Requires mobile phase optimization
GC	Volatile and thermally stable analytes	Not suitable for thermolabile APIs
UV-Vis	Compounds with chromophores	Lacks selectivity, prone to interference
FTIR	Structural characterization	Limited quantification capability
Titration	Acid/base or redox-active analytes	Low sensitivity, matrix-dependent
Potentiometry	pH and ionic measurements	Not selective for complex mixtures

5.3 Selection Process

1. Document justification for selected technique in Annexure-1.
2. If multiple techniques are applicable, conduct parallel trials for sensitivity, precision, and specificity.
3. Select technique providing best balance of robustness, sensitivity, specificity, and cost-effectiveness.

5.4 Case Examples

• API-A: UV method selected due to strong absorbance at 254 nm and minimal matrix interference.
• API-B: GC selected for quantifying residual solvents due to volatility profile.
• API-C: HPLC selected due to presence of multiple closely eluting impurities.

5.5 Documentation

1. Record selection process, rationale, trial results, and risk assessment in Annexure-2.
2. Store supporting chromatograms, spectrums, and validation feasibility data with the technique evaluation file.

5.6 Approval

1. Submit the documented technique selection sheet to QA for review.
2. Obtain final approval from AMD Head before initiating full method development.

6. Abbreviations

• API: Active Pharmaceutical Ingredient
• HPLC: High Performance Liquid Chromatography
• GC: Gas Chromatography
• UV: Ultraviolet Spectroscopy
• FTIR: Fourier Transform Infrared Spectroscopy

7. Documents

1. Annexure-1: Analytical Technique Selection Sheet
2. Annexure-2: Comparative Technique Evaluation Summary

8. References

• ICH Q2(R1) – Validation of Analytical Procedures
• USP General Chapters <1225>, <621>
• FDA Guidance for Industry – Analytical Procedures and Methods Validation

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name	Priya Menon	Harshad Shinde	Dr. Ritu Goyal
Designation	Scientist – AMD	QA Lead	Department Head
Department	Analytical Method Development	Quality Assurance	Analytical Method Development

11. Annexures

Annexure-1: Analytical Technique Selection Sheet

Product Name	Technique Considered	Selected Technique	Justification
Paracetamol Tablets	UV, HPLC	UV	Strong UV absorbance; minimal interference; cost-effective
Metronidazole API	GC, HPLC	HPLC	Non-volatile; impurity profiling needed

Annexure-2: Comparative Technique Evaluation Summary

Technique	LOD (µg/mL)	Precision (% RSD)	Specificity	Decision
UV	0.5	1.2	Low	Rejected
HPLC	0.1	0.8	High	Selected

Revision History

Revision Date	Revision No.	Change Description	Reason	Approved By
01/06/2025	2.0	Incorporated selection matrix and Annexure-2	Annual Review	Dr. Ritu Goyal
04/08/2022	1.0	Initial Issue	New SOP	QA Head