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How to Reduce Foreign Particles in GMP Cleanrooms

by | Nov 22, 2022

The Importance & Difficulty of Reducing Foreign Particles

In pharmaceutical manufacturing, the presence of discernible foreign particles is a serious flaw and one of the primary grounds for rejects, re-rework or even recalls. Foreign particles present at any point throughout the production process are regarded as contaminants and represent a risk to the ability to manage the manufacturing processes. For these reasons, any manufacturing step where particle contamination occurs results in a nonconformance or out-of-spec observation. To reduce the likelihood of repeated Non-Conforming Material Reports (NCMR), an inquiry is needed to determine the root-cause failure mechanism.

Current Foreign Particle Identification Practice

  1. Out-of-Spec Devices (OOS) are collected during inspection.
  2. If it is determined a CAPA is required, the facility may send the OOS Device to an outside Laboratory for Analytical Analysis.
    • SEM-EDX and FTIR are employed to characterize the contamination.
  3. Facility Receives Lab Results.
    • Often costly, time-consuming, and in many cases, does not allow for a root cause determination.
  4. The Issue.
    • Since only the device was analyzed, it is difficult to link the contamination to its source.
    • In most cases, labs will report findings such as “carbon-based material,” which is too vague to create practical actions.
    • Quite often, facilities partake in speculation. Is it our filtration system? Is it our garments?

Foamtec’s Foreign Particle Identification System

To address the GAP in the current practices, Foamtec has pioneered the PolyCHECK® Foreign Particle Identification System which combines tools and procedures that can audit the entire process and provide a root cause description of the failure mechanism.

  1. Out-of-Spec Devices (OOS) are collected during inspection.
  2. Employ Foamtec to Investigate the Issue
  3. Foamtec Performs Sample Collection
    • Foamtec will employ PolyCHECK® Wipes or Swabs to collect samples from all critical equipment surfaces.Our team will collect failed devices and process materials such as syringes, stoppers, vials, bags, conveyor components, tools, garments, gloves, consumables and filters.
    • PolyCHECK® sampling tools are ISO 5 processed and available gamma-irradiated to 10-6 SAL.
  4. Foamtec Performs Analytical Analysis
    • Using SEM/EDX with micrometer & FTIR instruments, a forensic analysis will be carried out of the contaminated device, the equipment surfaces, and the process materials to identify the source of the contamination.
  5. Facility Receives Lab Results
    • We will review lab results and make specific recommendations that address the root cause failure mechanism.
  6. The Difference
    • Foamtec’s PolyCHECK® collection process can collect a large number of samples in a short amount of time.
    • With a large sample size, Foamtec’s analytical team can pinpoint the contamination source.
    • Furthermore, our experienced team will consult with your facility to manage the FM reduction process.

Foamtec’s Foreign Particle Collection Tools

PolyCHECK® Wipes for Large Surfaces

PolyCHECK® is an ideal cleaning validation and failure analysis tool for particle contamination as it enables quality engineers to rapidly sample equipment surfaces to recover foreign particles in ISO 1-8 Cleanrooms.

PolyCHECK® Swabs for Small Surfaces

PolyCHECK® Swabs employ a white fabric on one side and a black fabric on the other side to give cleanroom professionals a unique particle detection tool.

Case Study at Pharmaceutical Manufacturer

Vial with Contamination

A large pharmaceutical company engaged with Foamtec to help identify contamination found in vials.

Foamtec’s Investigation

Foamtec’s PolyCHECK® Process can be carried out with minimal disruption while foreign particle sample collection takes place.

Foamtec’s Sampling Process

Foamtec’s experienced contamination specialists and the PolyCHECK wiper enable the facility’s critical surfaces, garments, process equipment, failed devices, and process materials to be analyzed.

Foamtec’s Analytical Lab

Foamtec’s analytical team ran SEM/EDX & FTIR analyses to determine the process and material sources of the contamination.

SEM/EDX Results

The PolyCHECK system’s excellent sample recovery enables SEM/EDX to provide visual and elemental characterization and size of the contamination.

Forensics Analysis

The large amount of sample allows us to use FTIR(Fourier-transform infrared spectroscopy) on the OOS devices and cross-reference them to process materials, tools, garments, gloves, consumables, etc.  The excellent sample recovery allows Foamtec to distinguish the molecular makeup between different organic materials.

SEM/EDX Fiber Dimensional Analysis

Once the FTIR results are in, we refer back to the SEM/EDX results to measure the size of the fibers and particle contamination. This also allows us to match organic foreign particle contamination to its material source(s).

Size of polyester fiber contamination found in vial.

Size of polyester fiber of the facility’s cleanroom polyester wipe.

Connecting Contamination to its Sources

OOS Product -> Material Source(s) -> Process Source(s)

The polyester fibers found in the vials and work surfaces matched the fibers from the facility’s cleanroom polyester wipes.

The cellulose fibers found on work surfaces matched the fibers from the facility’s cleanroom polycellulose wipes.

The polypropylene fibers found on work surfaces and cleanroom garments matched the fibers from the facility’s presaturated polypropylene wipes.

It was determined the root cause failure mechanism was particle and fiber shedding from the cleanroom wipes used to clean and disinfect the facility.

Key Takeaways

PolyCHECK® Process

+ Low-cost, Fast Process

+ Large Sample Size, Multiple Surfaces

+ Easy to collect FM from all surfaces

+ Available Sterile for Sampling Aseptic Environments

+ Minimal Operational Disruption

The PolyCHECK® FM service has been successful in the following situations:

+ CAPAs can be closed with a root cause understanding of the failure mechanism.

+ Facilities gain a deep understanding of the contamination signature of their process.

+ Identifying specific processes that generate dark foreign particles in parenteral drugs.

+ The PolyCHECK® process is both a risk assessment and cleaning validation tool.

+ Compliments USP 788, USP 789, USP 790 and USP 1788 methods.

+ Significantly reduce OOS events.

If your facility cannot identify sources of foreign particle contamination despite spending enormous resources, the PolyCHECK® FM Process can assist you.

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