Standard Operating Procedure for Microbial Limit Testing for Dispersible Tablets
| Department | Tablet |
|---|---|
| SOP No. | SOP/TAB/082/2025 |
| Supersedes | SOP/TAB/082/2022 |
| Page No. | Page 1 of 6 |
| Issue Date | 01/03/2026 |
| Effective Date | 06/03/2026 |
| Review Date | 01/03/2027 |
1. Purpose
To establish a procedure for microbial limit testing of dispersible tablets, ensuring that the tablets meet the required microbiological standards for safe consumption.
2. Scope
This SOP applies to the microbial limit testing of dispersible tablets to ensure they comply with the specified limits for microbial contamination as per regulatory standards.
3. Responsibilities
- Manufacturing Personnel: Responsible for providing representative samples of dispersible tablets for microbial testing and ensuring the tablets are free from visible defects.
- Quality Control (QC): Responsible for conducting the microbial limit tests, recording the results, and ensuring compliance with microbiological standards.
- Quality Assurance (QA): Ensures that the testing procedure is followed and reviews the results for batch approval and release.
4. Accountability
The QC Manager is accountable for ensuring that microbial limit testing is performed in compliance with this SOP and for reporting the results. The QA Manager is responsible for reviewing the results and approving the batch for release.
5. Procedure
5.1 Sample Collection
- Collect a representative sample of dispersible tablets from the batch, as specified in the batch record.
- The sample should consist of 6 tablets (or as specified in the batch record or pharmacopeial guidelines).
- Ensure that the tablets are free from defects such as cracks, chips, or contamination.
- Label the sample appropriately for identification during testing.
5.2 Preparation of Microbial Testing Apparatus
- Prepare the microbial testing apparatus, ensuring that it is clean and properly calibrated.
- Ensure that sterile equipment, including petri dishes, nutrient agar, and any necessary culture media, is available and prepared.
- Prepare an appropriate dilution of the sample tablets to obtain a suitable concentration for microbial testing.
5.3 Microbial Limit Test Procedure
- Prepare the tablet sample for testing by triturating or dissolving the required number of tablets in a suitable diluent, as per the pharmacopeial guidelines.
- Take an aliquot of the sample and inoculate it onto the prepared agar plates for microbial growth.
- Incubate the agar plates under suitable conditions for microbial growth (usually at 30°C–35°C for bacteria, and at 20°C–25°C for fungi, unless specified otherwise in the pharmacopeia).
- Allow the samples to incubate for the specified period (typically 48–72 hours), observing for any microbial growth.
5.4 Data Recording and Calculation
- After the incubation period, examine the plates for microbial growth, counting the number of colonies observed.
- Record the number of colony-forming units (CFUs) for each agar plate in the batch record (Annexure-1).
- Compare the results against the acceptance criteria specified in the batch record or pharmacopeial guidelines (e.g., total aerobic bacteria, yeast and molds, and specific pathogens).
5.5 Microbial Limit Test Acceptance Criteria
- Ensure that the tablet sample does not exceed the acceptable limit for microbial contamination, which is typically 1000 CFU/g for total aerobic bacteria and 100 CFU/g for yeast and molds, but may vary depending on the product specifications.
- If any sample exceeds the microbial limit, the batch should be investigated, and corrective actions should be documented in the deviation report (Annexure-2).
5.6 Documentation and Record-Keeping
- Document the microbial limit testing results, including the individual counts for each tablet sample, in the batch record (Annexure-1).
- Record any deviations from the microbial limit specifications in the deviation report (Annexure-2), along with the corrective actions taken.
- Ensure all records are signed, dated, and stored according to the company’s record retention policy for future audits and inspections.
5.7 Post-Test Cleanup
- Clean all equipment used in microbial testing, including petri dishes, dilution tubes, and culture media, according to the company’s cleaning SOP.
- Ensure that all testing equipment is properly stored and maintained in good working condition.
6. Abbreviations
- SOP: Standard Operating Procedure
- GMP: Good Manufacturing Practice
- QC: Quality Control
- QA: Quality Assurance
- CFU: Colony-Forming Unit
7. Documents
- Batch Record (Annexure-1)
- Deviation Report (Annexure-2)
8. References
- USP <61> – Microbial Limits
- 21 CFR Part 211 – Current Good Manufacturing Practice for Finished Pharmaceuticals (US FDA)
- European Pharmacopoeia (EP) – Microbial Limits for Tablets
9. SOP Version
Version: 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | |||
| Designation | |||
| Department |
11. Annexures
Annexure-1: Batch Record
| Batch Number | Tablet Sample | Microbial Count (CFU/g) | Microbial Type | Result |
|---|---|---|---|---|
| Batch 001 | 6 tablets | 500 | Total Aerobic Bacteria | Pass |
Annexure-2: Deviation Report
| Deviation Date | Batch Number | Deviation Description | Corrective Action | Responsible Person | |
|---|---|---|---|---|---|
| 10/12/2025 |
You said: html | Batch 001 | Microbial count exceeded specification | Investigated raw material supplier and adjusted process controls | John Doe |
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 Microbial Testing Protocol | Refined testing method and specifications | QA Head |