Rapid Microbiology Services


We currently provide programs for assessing product and technology compatibility/feasibility, method development and validation together with regulatory support. Once regulatory approval is obtained, technology and method can be transferred to the manufacturing site if decided to insource, or testing can be provided by Nelson Labs Europe. We support you in overcoming hurdles such as large equipment investments, having a multi-disciplinary team available (technical, validation, quality and regulatory experts) and time constraints.

Current RAPID micro services include:

  • Sterility testing (< 4 hours)
  • Microbial Limit testing of non-sterile products (2 days)
  • Microbial quality control of pharmaceutical water and cell growth medium (< 4 hours)
  • Environmental Monitoring (4 hours)
  • Endotoxin testing (2 hours)

Do you have microbial “Out-of-Specs” in product sterility testing or in-process monitoring?
Get objective confirmation of your results today! Contact us for express sample pick-up services.



The largest part of microbial assays as mentioned in the pharmacopeia such as microbial limit test and sterility test were developed at the end of the 19th century. These methods remain the principle tests in pharmaceutical, microbiological quality control because of:

  • their technical and scientifically simplicity
  • the low consumable and equipment costs
  • the acceptance of these methods by regulatory agencies


Because of the reasons mentioned above, quality testing in the pharmaceutical and medical industry is limited to these simple, traditional methods.

Traditional microbiological methods, however, have important limitations originating from the fact that most of these methods are based on the occurrence of microbial growth to obtain a sufficient concentration for visible colonies on solid growth media or the appearance of turbidity in fluid media.

Micro-organisms that will not grow in the selected growth conditions (growth media, temperature) or micro-organisms that have lost the ability to reproduction will not be detected. Examples of pathogens that occur in a hospital environment and cannot be detected by traditional methods are Campylobacter jejuni and Campylobacter coli. Both organisms grow and multiply at temperatures between 37°C to 42°C and will thus not be detected at temperatures specified by the pharmacopeia (20-25°C and 30-35°C).

The biggest disadvantage to traditional, growth based methods is the time needed for results. The time needed to obtain a sufficient visual detectable concentration ranges somewhere between 2 and 14 days (sterility test). The inability to obtain timely results for microbiological quality control may lead to less control over the production environment and increased production costs (inventory costs, batch rejection, etc.).

Biopharmaceutical products with a short shelf-life suffer even more from this time delay since results may only be obtained after product expiration.

The implementation of Rapid Microbiological Methods for Batch Release and/or In-Process-Control can result in substantial economical and scientific benefits even though most of the alternative methods require a substantial initial investment.

One of these costs is the validation that these methods require since they are not pharmacopeial method. However, guidance on validation of alternative microbiological methods can be found in pharmacopeia and PDA:

  • E.P. 5.1.6
  • USP <1223>
  • PDA TR 33 

Contact Nelson Labs Europe for a suggested validation approach, which is an essential part of the "Post Approval Change Management Protocol", for the approval of a rapid sterility test in support of batch release testing or for In Process Control testing services.



Rapid Microbiological Methods can roughly be subdivided into two groups: those that rely on microbial growth and those that do not. Examples of the first group are methods based on ATP-bioluminicence, CO2 production and micro colony detection. Examples of the non-growth based group are methods based on flow or solid phase cytometry and nucleic acid amplification.

Growth based methods, although being faster than traditional methods, still require several days to result. They also suffer from some of the same problems: if an organism cannot grow it cannot be detected.

Only non-growth based methods are able to provide results within several hours and are able to detect all viable organisms.

Nelson Labs Europe applies the AES Chemunex technology based on fluorescent viability staining and detection by solid phase cytometry.


Principle of Solid Phase Cytometry

This method is based on a fluorescent labeling of viable cells. After filtration of the test item, the filter is treated with a non-fluorescent molecule. Due to intrinsic esterase activity of viable cells, the molecule will be reduced and a fluorochrome will be released. Living cells with an intact cell membrane are capable of retaining and accumulating this fluorochrome. A laser scanner detects and locates the fluorescent signals originating from the fluorochrome.

This would reduce the time needed for a detection of a single micro-organism to several hours!


The biggest advantages of this method are the very quick turn-around time and the independence from micro-biological growth which avoids problems which might arise from growth inhibition.


The test protocol consists of the following steps:

  • Filtratrion of the samples over a 0.45 µm membrane filter
  • Prelabeling of the samples needed for metabolic activation organisms (3 hours)
  • Fluorescent labeling of viable organisms (45 minutes)
  • Solid Phase Cytometer scanning (4 minutes)
  • Confirmation under a fluorescence microscope  

More information on the  ScanRDI® system can be found on the AES Chemunex website:

Rapid Microbiology Benefits:

  • Superior production control
  • Shorter time to correction
  • Shorter time to root cause  identification
  • Efficient control and monitoring of critical process parameters 
  • Less batch rejections
  • Lower laboratory and warehouse inventories
  • Shorter time-to-market


Mr. Kevin Breesch, MSc
Manager Business Development International Preclinical


Nelson Labs Europe | Microbiology RMM
Rapid microbiology services; Method validation; rapid sterility testing; water; bioburden; non sterile products; GMP laboratory
Rapid microbiology services; Method validation; rapid sterility testing; water; bioburden; non sterile products; GMP laboratory