Sterility Testing of Pharmaceutical and Medicinal Products

At ifp manufacturers have access to equipment suitable for testing drugs and medicinal products manufactured under aseptic conditions for sterility as per Ph. Eur. 8, 2.6.1. Thus, we examine sterile products under aseptic testing conditions for compliance with the Pharmacopoeia. Due to the use of an isolator (sterile box), all measures for preventing contamination are taken, which is the basic prerequisite for sterility testing compliant with the Ph. Eur. You want to have your products tested for sterility or require professional advice on this matter? Please call us. We will gladly discuss your specific requirements with you.

Testing sterile pharmaceuticals and medicinal products in the isolator

At ifp sterility testing is customized to your specific product. The products we test range from parenterals in various administration forms right up to medicinal products designed for application to humans and animals.

• watery solutions, e.g. injectables
• soluble powders
• oils and oily solutions, e.g. ophthalmics
• ointments and cremes
• infusion bags
• implants, e.g. heart valves or stents
• catgut and other surgical suture material

Aseptic testing environment through decontamination of material and working area

The isolator used in our lab has a short H₂O₂-based (hydrogen peroxide) decontamination cycle. The H₂O₂ is evaporated in order to ensure extensive decontamination of all materials within the working area or sluice. Apart from creating aseptic working conditions, the programmed cycle subsequently always restores an H₂O₂-free atmosphere, so that false-negative results can be ruled out for the next sterility test performed. Please contact us about any questions regarding qualification / validation of the system.

Sterility tests using membrane filtration or direct inoculation

Sterility testing is preferably done by membrane filtration using a max. pore size of 0.45 µm, provided the product permits this. If the product is not a directly filtrable substance, it can be dissolved or diluted in watery or oily solvent before filtering. In this case it is essential to ensure that the solvent used does not have anti-microbial properties, since this would influence the sterility test negatively. If this is not the case or if the product is not soluble (e.g. implants, surgical suture material), sterility testing is done using direct inoculation, i.e. the product is placed directly into the culture medium. We will gladly discuss with you which method would suit your product best. Ask our experts.

Method validation: checking the performance of the sterility test

Appropriate controls are indispensable if the test results gained are to be valid. Hence, validation or performance tests of the sterility test are important in addition to environmental and negative controls. These tests are done when a new product is tested for the first time or when the testing conditions have been changed. Performance tests serve to confirm that the anti-microbial activity of the product to be tested has been sufficiently removed. Performed in the same way as the actual product test, an additional defined quantity of replication-competent microorganisms is added to the filter, or into the culture medium into which the product is placed directly. The suitability of the method results from comparing the microbial growth with a parallel positive control (spiked medium without product). If both media – with and without the product – evince comparable growth, the performance test was successful. If the culture medium with the product shows less growth compared to the positive control, the anti-microbial properties of the product were not sufficiently removed. In this case, the testing conditions must be modified. We will gladly carry out these validations for you – naturally in close coordination with you. Please contact us for a comprehensive consultation regarding any of your requests.