Laura Ahola

The NRU assay is a quantitative test to determine the potential biological reactivity of a mammalian cell culture in response to a medical device extract. It is described in Annex A of ISO 10993-5 and is one of the most commonly used methods for medical device cytotoxicity testing. The test item is extracted in cell culture medium, which is suitable for both polar and non-polar extracts. The cells are exposed to the extract, and their viability is assessed after staining with neutral red (NR) solution. The number of viable cells correlates with the color intensity determined by photometric measurements, as non-viable cells do not absorb NR. The medical device is considered non-cytotoxic if the percentage of viable cells is ≥ 70 % of the untreated control.

Assessment of skin sensitization potential using the ARE-Nrf2 luciferase test method outlined in OECD Test Guideline 442D and listed in Annex C of ISO 10993-10 as an in-vitro alternative to traditional in vivo sensitization tests. The method has been validated for medical device extracts. The assay models the keratinocyte activation pathway — key event 2 in the skin sensitization adverse outcome pathway (AOP) as described by the OECD. Human keratinocytes are exposed to the test substance at a range of concentrations. If the substance has skin sensitization potential, it activates the Nrf2 transcription factor, which binds to the antioxidant response element (ARE) and induces luciferase expression. The measured luciferase activity thus correlates with the sensitization potential of the substance. According to Annex C of ISO 10993-10, a substance is classified as a skin sensitizer if luciferase activity increases by 50% relative to the solvent control at a concentration where cell viability is not significantly reduced. Two extracts (one polar and one non-polar) are prepared per tested device, and testing is performed in duplicate for each solvent.

We offer comprehensive test packages for verifying the quality of type II and type IIR face masks according to the EN 14683 standard. The tests included in the packages are required to label face masks with the CE marking. Medical face masks are divided into Types I and II according to their bacterial filtration efficiency. Type I masks are not intended for healthcare professionals, but for the public to prevent the spread of infectious diseases. Type II masks are further classified based on whether they are splash-resistant (Type IIR) or not (Type II). To comply with the European Standard EN 14683, Type II face masks must undergo the following quality tests: Bacterial filtration efficiency (BFE) - The ability of the face mask to filter the bacterium Staphylococcus aureus. The BFE is expressed as the percentage of colony-forming units (cfu) that have passed via aerosol through the facemask. If a face mask consists of two or more areas with different characteristics, these areas will be tested separately., Breathability (Differential pressure) - The amount of differential pressure required to draw air through a measured surface area at a constant flow rate., Microbial cleanliness (Bioburden) - The measurement of colony forming units per gram as per EN ISO 11737-1., Biocompatibility - The medical face mask manufacturer shall complete a biocompatibility evaluation according to ISO 10993-1 as a surface device with limited contact. The applicable toxicology testing regimen shall also be determined.. In addition to the above, Type IIR masks require the following test: Splash resistance - Performed according to ISO 22609, this test determines the ability of a face mask to resist penetration of splashes of liquid at different pressures.. The lower displayed price applies to the Type II mask test package, while the higher price also includes the splash resistance test required for Type IIR masks.

Microbiological test package for pharmaceutical or cosmetic products and ingredients according to European Pharmacopoeia methods Ph. Eur. 2.6.12 and Ph. Eur. 2.6.13. The most recent edition of the pharmacopoeia is followed. The following parameters can be included in the analysis package: Total aerobic microbial count (TAMC) according to Ph. Eur. 2.6.12, Total combined yeasts and moulds count (TYMC) according to Ph. Eur. 2.6.12, Tests for specified microorganisms according to Ph. Eur. 2.6.13, including e.g., S. aureus, P. aeruginosa, E. coli, and C. albicans. These analyses are commonly conducted on the finished product and/or starting materials and intermediates as part of pharmaceutical batch release testing.