The cytotoxicity test is designed to assess the overall toxicity of medical devices and materials. The test involves extracting devices in a cell culture medium and then exposing the extract liquid to mouse fibroblast cells (L929). Cells are allowed to grow in the extract liquid for a certain period of time before being evaluated using qualitative or quantitative methods. The test is carried out on all medical devices, raw materials and devices for cleaning validation or residue production that come into contact with the patient.
MEM Elution
Devices / materials are usually extracted at 37 ± 1ºC in serum-supplemented mammalian cell culture medium (MEM). After extraction, the extracts are contacted with a single layer of L-929 cells (mouse fibroblasts). Cells are then allowed to grow in the extraction fluid for a certain period of time before being evaluated using qualitative or quantitative methods.
Qualitative
Qualitative evaluation involves observing cells under a microscope and assigning a cytotoxic grade (0-4). The grade is based on an estimated percent lysis (death) and morphology (appearance) of cells. If the cytotoxic score ≤ 2 (50 %% lysis), the test materials pass the test.
Quantitative
Quantitative evaluation uses a tetrazolium stain, which is used to evaluate the metabolic activity of cells. Results are reported as percent viability (percent of living cells). Test materials pass the test if the viability percentage is 70 XNUMX%. Multiple dilutions of test substance extract are usually included in each test.
Agar shared
The material is placed on an agarose layer that is placed on top of a single layer of L-929 cells and incubated in 24% ± 26 CO37 at 1 ± 5 ° C for 1 - 2 hours. After incubation, the cell destruction site is measured and scored on the 10993-5 scale listed in AAMI / ANSI / ISO 0-4. If the cytotoxic response is not greater than grade 2 (slightly reactive), the material meets ISO requirements. Although Agar Overlay is a historically accepted test method, it may be appropriate when it is sent to some regulatory agencies.
Cytotoxicity Errors
Sometimes, a device or material will exhibit a level of cytotoxic reactivity that is higher than the ANSI / AAMI / ISO 10993-5 standard and will result in a failed test. While your product has failed the cytotoxicity test, it does not mean your device or material is not safe for clinical use. This simply means that you have to identify the source of the error and evaluate any toxicological risk.
Our Experts Can Help
There are several possible causes of cytotoxicity failure and EUROLABprovides services to help you identify and evaluate the error. Our experts can evaluate possible toxicological risks for patient safety.
We evaluate the materials and processes associated with the device. Based on this information, our experts will usually recommend targeted analytical chemistry to determine the cause of the failure. We can then work with customers to justify the error through testing and evaluation.
As a result of consultations with our experts to identify the cause of cytotoxicity failure and develop an action plan, it leads manufacturers to successfully send their devices for regulatory approval without further action.
EUROLAB, with its highly expert team and internationally accredited laboratories, Cytotoxicity Test It performs all test, analysis, measurement, evaluation and report generation services completely and reliably.
To get an appointment, to get more detailed information or to request an evaluation, you can ask us to fill in our form and reach you.
