Primary Packing Material Sampling and Testing directly contact pharmaceutical products and play a critical role in maintaining product quality and patient safety. Even if the drug product is manufactured under GMP conditions, contaminated packaging materials can introduce microorganisms, leading to product contamination, batch rejection, or regulatory observations.
This article explains the complete GMP procedure for sampling and microbiological testing of primary packing materials such as poly bags using the swab method and pour plate technique.
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Purpose for Primary Packing Material Sampling:
The objective of this procedure is to describe the standardized method for microbiological sampling and testing of primary packing materials, including poly bags, to ensure compliance with approved specifications before use in pharmaceutical manufacturing.
Scope:
This procedure applies to microbiological sampling and testing of non-sterile primary packing materials received in the warehouse for use in pharmaceutical manufacturing.
Responsibility:
| Designation | Responsibilities |
| Officer/Executive of Microbiology department | Verify receipt of sampling request. Perform sampling according to the approved sampling plan. Carry out testing as per approved specifications and test methods. Record observations and analytical results. Recommend release or rejection of the material. |
| Officer/Executive of Warehouse department | Receive and store incoming materials under specified conditions. Assign “Under Test” status until QC approval. Provide material for sampling. Release approved material for production only after QA authorization. |
| Officer/Executive of Quality Assurance Department | Review sampling and testing records. Approve release or rejection of primary packing materials. Ensure compliance with GMP requirements. Investigate any non-conformities or deviations. |
Procedure for Primary Packing Material Sampling and Testing
Receipt of Material
Receive primary packing materials in the designated quarantine area.
Verify the material name, batch number, supplier details, quantity, and packaging condition.
Ensure each container is properly identified with the material status label.
Store the material under the recommended environmental conditions until sampling.
Precautions During Sampling
Sampling shall be performed only by trained microbiology personnel.
Personnel shall wear sterile gloves, mask, head cover, and laboratory gown.
Sampling shall be carried out in a classified sampling area or under a Laminar Air Flow (LAF) workstation, where applicable.
Use only sterile sampling tools and sterile sampling bags or containers.
Avoid direct hand contact with the product-contact surface of the packaging material.
Maintain aseptic techniques throughout the sampling activity.
Swab Preparation for sampling:
Prepare buffer peptone solution or 0.9% saline solution.
Sterile by autoclaving at 121°C for 15minutes.
Take 10ml sterile peptone buffer or normal saline solution into the test tube and dip the swab stick into it.
Prepare such tubes as per requirement.
Requirements for Primary Packing Material Sampling and Testing:
| Equipment | Purpose |
|---|---|
| Sterile Swab | Surface sampling |
| Sterile Test Tube | Sample collection |
| Buffer Peptone Water | Swab moistening |
| Normal Saline | Alternative diluent |
| Sterile Gloves | Prevent contamination |
| Micropipette | Sample transfer |
| Vortex Mixer | Microorganism recovery |
| Sterile Petri Plates | Pour Plate Method |
| SCDA | TAMC |
| SDA | TYMC |
Sampling Procedure for swab method of Primary Packing Material Sampling and Testing
Sampling Procedure
Collect all the required sampling materials and place them in a clean, sanitized stainless steel sampling container before entering the sampling area.
Switch ON the Laminar Air Flow (LAF) unit at least 15 minutes before starting the sampling activity. Verify that the differential pressure gauge is within the specified operating range before use.
Wear the appropriate personal protective equipment (PPE), including sterile gloves, face mask, head cover, and laboratory gown, before entering the sampling area. Ensure that the sampling area and the LAF work surface have been cleaned and sanitized as per the applicable cleaning procedure.
Perform the sampling of the non-sterile poly bag under the LAF to minimize the risk of contamination.
Remove a sterile test tube containing 10 mL of sterile peptone water or normal saline and a sterile swab from the sampling kit. Label the test tube with the material name, batch/lot number, sampling date, and other relevant details, if not already labeled.
Randomly select the required poly bag(s) from the batch and transfer them into the sampling booth or under the LAF for sampling.
Moisten the sterile swab with the sterile diluent and swab a 25 cm² (5 cm × 5 cm) area of the poly bag surface. Swab the selected area using horizontal strokes followed by vertical strokes, ensuring complete coverage of the marked area.
Immediately after swabbing, aseptically place the swab back into the test tube containing 10 mL of sterile diluent and securely close the tube.
Submit the collected sample to the Microbiology Laboratory for analysis in accordance with the approved test procedure.
Sampling shall be performed only by authorized and trained Microbiology personnel following aseptic techniques throughout the procedure.
Procedure for Primary Packing Material Sampling and Testing by pour plate method:
Perform all microbiological testing under a qualified Laminar Air Flow (LAF) workstation using aseptic techniques.
Remove the sampled swab tube and vortex the tube for 1–2 minutes to ensure that any microorganisms present on the swab are adequately released into the sterile diluent.
Prepare the required culture media according to the approved media preparation procedure and ensure that the media meet all quality control requirements before use.
For Total Aerobic Microbial Count (TAMC), aseptically transfer 1 mL of the sample suspension into each of two sterile 90 mm Petri plates (in duplicate). Pour 15–20 mL of molten Soybean Casein Digest Agar (SCDA) into each plate, gently mix by rotating the plates, and allow the medium to solidify.
After solidification, incubate the test plates along with the appropriate positive and negative controls at 30–35°C for 3–5 days. Following incubation, examine the plates and record the bacterial colony count.
For Total Yeast and Mold Count (TYMC), aseptically transfer 1 mL of the sample suspension into each of two sterile 90 mm Petri plates (in duplicate). Add 15–20 mL of molten Sabouraud Dextrose Agar (SDA) to each plate, gently mix, and allow the medium to solidify.
After solidification, incubate the test plates together with the appropriate positive and negative controls at 20–25°C for 5–7 days. After incubation, examine the plates and record the yeast and mold colony count.
Compare the observed microbial counts with the approved acceptance criteria and document all results in the microbiological test record.
Microbiological analysis of non-sterile poly bags shall be performed only when specified in the approved sampling plan, material specification, customer requirement, investigation, or as directed by Quality Assurance (QA).
Acceptance Criteria for Primary Packing Material Sampling and Testing
The microbiological acceptance criteria shall be as specified in the approved material specification.
Generally:
- TAMC shall comply with the specified limit.
- TYMC shall comply with the specified limit.
- Specified microorganisms shall be absent where required.
- Sterility requirements shall be met for sterile packaging components.
Abbreviations used:
| Abbreviation | Description |
| SOP | Standard Operating Procedure |
| QC | Quality Control |
| QA | Quality Assurance |
| LAF | Laminar Air Flow |
| GMP | Good Manufacturing Practices |
| TAMC | Total Aerobic Microbial Count |
| TYMC | Total Yeast and Mold Count |
| CFU | Colony Forming Unit |
| OOS | Out of Specification |
| PPE | Personal Protective Equipment |
Change History:
| Effective Date | Details of Revision | Change Control No. | Reason For Revision |
FAQ’s for Primary Packing Material Sampling and Testing
Q-1 Why is microbiological testing of primary packing materials required?
Answer: Microbiological testing is performed to verify that primary packing materials are free from unacceptable levels of microorganisms before they come into contact with pharmaceutical products.
Q-2 What are primary packing materials?
Answer: Primary packing materials are packaging components that come into direct contact with the pharmaceutical product.
Q-3 Who is authorized to perform sampling?
Answer: Only trained and authorized personnel from the Microbiology department are permitted to perform sampling.
Q-4 Why should sampling be performed under a Laminar Air Flow (LAF) unit?
Answer: Sampling under a qualified LAF provides a clean environment with filtered air, minimizing the possibility of environmental contamination during sample collection and microbiological analysis.
Q-5 Why is the LAF switched on at least 15 minutes before sampling?
Answer: Operating the LAF for at least 15 minutes allows the airflow to stabilize and helps remove airborne particles.