specified organism tests.

2. Scope

This SOP is applicable to method development and validation activities conducted in the Analytical Method Development (AMD) department for tablets, capsules, syrups, creams, ointments, and APIs that are tested for microbial load as per USP <61> and <62>.

3. Responsibilities

• Microbiologist: Performs suitability testing by spiking known organisms into the product and documenting microbial recovery.
• Formulation Scientist: Provides information on formulation matrix and possible inhibitory ingredients.
• QA Executive: Verifies that suitability results meet pharmacopeial acceptance criteria and signs the validation report.

4. Accountability

The Head of Analytical Method Development is accountable for ensuring all non-sterile product testing methods pass suitability validation before being adopted for routine microbial analysis.

5. Procedure

5.1 Selection of Microorganisms

1. Use the following compendial strains:
   • Staphylococcus aureus ATCC 6538
   • Escherichia coli ATCC 8739
   • Pseudomonas aeruginosa ATCC 9027
   • Salmonella typhimurium ATCC 14028
   • Clostridium sporogenes ATCC 11437 (if applicable)
   • Candida albicans ATCC 10231
   • Aspergillus brasiliensis ATCC 16404

5.2 Sample Preparation

1. Dissolve or dilute product as per USP <61> instructions using sterile peptone water or appropriate diluent.
2. Prepare triplicate test units for each organism.

5.3 Inoculation and Recovery

1. Add ~100 CFU of each organism to the sample and mix thoroughly.
2. In parallel, spike the same number of CFU into blank media (positive control).
3. Use appropriate media:
   • Plate Count Agar for bacteria
   • Sabouraud Dextrose Agar for yeasts and molds
4. Incubate:
   • Bacteria: 30–35°C for 3–5 days
   • Fungi: 20–25°C for 5–7 days

5.4 Acceptance Criteria

1. Recovery from the product should be at least 70% of the positive control.
2. If recovery is below 70%, neutralizers or sample preparation changes must be implemented.

5.5 Documentation

1. Document raw counts, control counts, and % recovery in Annexure-1.
2. Record media, incubation, and neutralizer details in Annexure-2.
3. Prepare a method suitability report (Annexure-3) reviewed by QA.

6. Abbreviations

• SOP: Standard Operating Procedure
• CFU: Colony Forming Units
• QA: Quality Assurance
• USP: United States Pharmacopeia

7. Documents

1. Method Suitability Raw Data Sheet – Annexure-1
2. Media and Neutralizer Log – Annexure-2
3. Method Suitability Summary Report – Annexure-3

8. References

• USP <61> Microbiological Examination of Nonsterile Products
• USP <62> Tests for Specified Microorganisms
• Ph. Eur. 2.6.12, 2.6.13
• ICH Q6A Specifications

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name	Deepika Shastri	Ravi Kulkarni	Sunita Reddy
Designation	Microbiologist	QA Reviewer	Head – AMD
Department	Analytical Method Development	QA	Analytical Method Development

11. Annexures

Annexure-1: Method Suitability Raw Data Sheet

Organism	CFU Recovered (Product)	CFU Recovered (Control)	Recovery (%)	Status
C. albicans	76	92	82.6%	Pass

Annexure-2: Media and Neutralizer Log

Media	Batch No.	Neutralizer Used	QC Result
PCA	PCA-2025-08	Polysorbate 80 + Lecithin	Growth Promotion Pass

Annexure-3: Method Suitability Summary Report

The non-sterile oral suspension formulation exhibited no significant inhibition of microbial recovery. All organisms showed ≥70% recovery. Method deemed suitable for enumeration and specified organism testing.

Revision History:

Revision Date	Revision No.	Details	Reason	Approved By
21/05/2025	2.0	Included validation for neutralizer compatibility and specified organism testing	Annual SOP Review	Sunita Reddy
05/05/2022	1.0	Initial SOP Release	New SOP	QA Head