Timothy Cser
Senior Technology Specialist
MilliporeSigma
Didier Hélal, Ph.D.
Chief Business Development Officer
Plair SA
Which type of pharmaceutical facilities should consider technologies that continuously monitor ambient air for microbial contamination in real-time?
Continuous real-time air monitoring is becoming essential for pharmaceutical facilities that operate in critical Grade A environments, for example in gloved or gloveless isolators or in aseptic fill and finish lines, where highly sensitive sterile products requiring stringent contamination controls are handled. These facilities are increasingly seeing the need to adapt their environmental monitoring strategies as a consequence of the EU GMP Annex 1 revision and other recent regulations that have emphasized continuous monitoring to detect transient contamination events. Regulatory bodies are advocating rapid and automated methods for contamination control, making real-time monitoring a best practice that is promoted for consideration. Real-time data raises immediate awareness of any environmental deviation along the production process. The risk of product contamination is significantly reduced if microbial events are detected as soon as they occur and addressed without delay.
What technologies are currently available for real-time microbial air monitoring?
Basically only Biofluorescent Particle Counters (BFPCs). They use laser-induced fluorescence (LIF) to detect particles exhibiting fluorescence signatures associated with biological material. When airborne particles pass through the detection chamber, they are illuminated by light of specific excitation wavelengths. The emitted fluorescence signal is then analyzed to differentiate between total particles and particles showing fluorescence emitted by biological structures. The Rapid-C+ Biofluorescent Particle Counter, for example, uses certain wavelengths for LIF excitation combined with a sophisticated analysis of fluorescence emission patterns. This, combined with particle morphology evaluation, allows for more effective distinction between viable particles and other fluorescent but non-viable interferers commonly present in cleanroom environments such as disinfectants or packaging materials. The instrument’s multi-parameter capability enhances the reliability of fluorescence interpretation, providing a clearer picture of the microbial environment within the facility.
Why is it important to perform conventional air sampling alongside real-time monitoring?
Performing conventional air sampling simultaneously remains crucial for several reasons, especially to meet regulatory demands such as Good Manufacturing Practices (GMP). While real-time technology continuously monitors for airborne contaminants, conventional microbiological methods allow the necessary subsequent identification and characterization of the microbial contaminant. By combining conventional sampling with real-time monitoring, facilities can identify microorganisms down to the species level, which is essential for root cause analysis and understanding local microbial flora. Customer validation is also significantly easier if colony forming units (CFUs) are determined simultaneously to running the alternative method, and even more so if the instrument’s manufacturer can provide robust validation data.
The Rapid-C+ instrument integrates an impaction-based active air sampler, which is independently validated for both physical and biological collection efficiency. This allows conventional microbiological air monitoring to be performed alongside continuous rapid monitoring. Plates are handled only outside the critical sampling locations, which is safer and faster, increasing the available production time on the filling line. It is possible to prepare plates under a separate laminar flow hood or, to reduce cross-contamination risks even further, use ready-to-use media such as ICR/ICRplus Settle Plates.
What prerequisites should facilities consider before implementing continuous real-time microbial air monitoring?
There are several prerequisites to consider. For new manufacturing isolators or aseptic filling lines, continuous real-time monitoring should be considered as early as in the planning stage. This ensures that the necessary infrastructure and technology are in place from the outset. Existing filling lines must be assessed as to whether retrofitting real-time monitoring systems is feasible, taking into account how long production will be disrupted.
Validation is another critical aspect. Facilities must review available primary validation data provided by the manufacturer and determine the additional work required to complete site-specific Performance Qualification (PQ). These studies confirm that the monitoring system performs reliably under real production conditions. Facilities must also ensure that their monitoring system complies with GMP guidelines, applicable ISO standards and pharmacopeial guidance. This is necessary to maintain product quality, safety and long-term operational reliability.
Could you summarize the key takeaways regarding continuous real-time microbial air monitoring in pharmaceutical facilities?
Continuous real-time microbial air monitoring is a tremendous advantage for pharmaceutical manufacturing facilities, particularly those operating in isolators and automated aseptic processing environments. By detecting microbial contamination in real time, and thereby enabling immediate corrective action, BFPCs like the Rapid-C+ system can save valuable time, effort and costs. The air is continuously monitored for contaminants, enabling earlier detection of deviations and improved understanding of cleanroom dynamics. Simultaneous conventional air sampling further enhances data comprehensiveness and helps meet regulatory demands.
When properly integrated through appropriate design planning, validation and alignment with regulatory expectations, continuous monitoring can strengthen contamination control strategies and support the consistent production of safe sterile medicines. Facilities should consider BFPCs for new installations and evaluate retrofitting options. Implementation ultimately helps to ensure the safety of the product and the efficiency of manufacturing, while positioning the facility as a leader in compliance and innovation.
Subscribe to our e-Newsletters
Stay up to date with the latest news, articles, and events. Plus, get special
offers from American Pharmaceutical Review delivered to your inbox!
Sign up now!