Particle counting according to ph. eur. 2.9.19 (Method 2)
Would you like to carry out particle counting according to Ph. Eur. 2.9.19 Method 2?
Ensure the purity of your injectable preparations and infusions
In the pharmaceutical sector, patient safety is a priority. Contamination by particles invisible to the naked eye in injectable preparations represents a critical health risk (embolism, immune reactions).
Ensure the compliance and safety of your injectable preparations with FILAB laboratory, an expert in particle counting according to the European Pharmacopoeia 2.9.19 Method 2 by Optical Microscopy (OM). Our accredited laboratory carries out precise analysis to detect and quantify visible and sub-visible particles, guaranteeing the quality and integrity of your pharmaceutical products.
What is Method 2 of ph. eur. 2.9.19?
Method 2 is based on particle counting and measurement by optical microscopy. Unlike Ph. Eur. 2.9.19 Method 1 (light obscuration), this approach allows direct, visual, and individual observation of sub-visible contaminants.
The technical principle
A defined volume of your sample is vacuum-filtered through a microporous membrane that retains all particles. The membrane is then dried and analyzed under a microscope by a qualified operator or an automated image analysis system under specific lighting.
In which cases should Method 2 be used?
For products that interfere with light blockage (highly viscous solutions, emulsions, suspensions, highly colored products, or products prone to microbubbles).
When a batch fails Method 1, Method 2 makes it possible to confirm the result and observe the shape or color of the particles to identify their origin (fibers, glass, plastic, etc.).
Regulatory thresholds (ph. eur. 2.9.19)
Requirements vary depending on the nominal volume of the container:
| Container volume | Particle size | Maximum limit per container / mL |
| Large Volumes (> 100 mL) | >= 10 µm >= 25 µm | 12 per mL 2 per mL |
| Small Volumes (<= 100 mL) | >= 10 µm >=25µm | 3000 per container 300 per container |
FILAB laboratory provides particle counting by OM (Optical Microscope) for injectable solutions: vaccines
Our key services
- Routine analysis and batch release for your finished products.
Stability testing to monitor particle evolution over time.
Method development and validation specific to your matrices (adaptations may be required if the product is viscous or prone to microbubbles).
Support in the event of an Out-of-Specification (OOS): if thresholds are exceeded, we help you investigate (with the option to switch to Method 2 by optical microscopy to identify the nature of the particles).
Why choose FILAB laboratory for particle counting according to Ph. Eur. 2.9.19 Method 2?
FILAB offers industrial companies specializing in the medical and pharmaceutical sectors technical expertise and a state-of-the-art analytical platform to respond as effectively and quickly as possible (with the option of carrying out these analysis urgently) to their requests and provide the most suitable services and tailored support.
To address these issues with precision and reliability, FILAB offers tailored support for particle counting according to Method 2 of Ph. Eur. 2.9.19, as well as for other standards…
FILAB is COFRAC ISO 17025 accredited
FILAB, accredited to COFRAC ISO 17025, guarantees reliable analysis that comply with the requirements of the European Pharmacopoeia for particle counting in injectable products. This accreditation demonstrates our expertise and our commitment to delivering accurate results to ensure the safety and compliance of your pharmaceutical formulations.
- Foreign body and/or contaminant identification by SEM-EDX and binocular micro-infrared spectroscopy, according to Ph. Eur. 2.9.52 standards
- Particle count testing by optical microscopy and image analysis, according to USP 788/789 and Ph. Eur. 2.9.19 (Method 2)
- Particle counting by optical microscope according to current standards: ISO 19227, ISO 10993-19, USP 788, Ph. Eur. 2.9.19, AAMI TIR 42
- Particle identification by SEM-EDX and µ-IRTF according to current standards: ISO 10993-19, Ph. Eur. 2.9.52, Ph. Eur. 2.2.24, AAMI TIR 42
Find the standards FILAB masters for performing particulate counting:
Our FAQ
To get a quote, you can contact our teams via our contact form, by phone, or by email.
All you need to do is send us your requirements (material type, requested analysis, any applicable standard, urgency, number of samples, etc.). We will then send you a personalized technical and pricing proposal within 24-48 hours.
Lead times vary depending on the nature of the analysis and the complexity of the expert assessment project.
However, FILAB is committed to providing fast turnaround times tailored to your constraints and industrial urgencies.
Method 2 of the European Pharmacopoeia 2.9.19 is a non-visible particle counting method based on microscopy. It makes it possible to detect and quantify particles present in injectable preparations when the light blockage method (Method 1) is not suitable.
Method 2 is used in particular for products with low transparency, high viscosity, or when the results obtained by Method 1 require further investigation. It is particularly suitable for certain suspensions, emulsions, or complex biological formulations.
The sample is filtered through a suitable membrane. The retained particles are then observed and counted under an optical microscope using an image analysis system. This approach makes it possible to assess the number of particles present across different size classes.
The microscopy method offers several advantages:
- ability to analyze cloudy or viscous products;
- direct visualization of particles;
- support for investigations in the event of contamination;
- complement to analysis performed by light blockage;
- better understanding of the nature of the particles observed.
Method 1 is based on the principle of light blockage and is the preferred method for subvisible particle control. Method 2 is based on microscopic observation and is used when Method 1 is not applicable or when further investigations are required. Both methods are described in the European Pharmacopoeia 2.9.19.
No. Method 2 mainly makes it possible to count particles. However, when contamination is detected, additional analysis can be carried out to characterize their chemical composition or origin, for example by SEM-EDX or micro-FTIR.