Importance of Bioburden and Biocompatibility Testing

1. Importance of Bioburden and Biocompatibility Testing

2. What is Bioburden Testing? • The presence of microorganisms on a surface (or complete item), inside a device, or from a portion of liquid before sterilization can help to ensure that the device is sterile. Bioburden can be introduced from the raw materials used in the manufacturing process, via the workforce or manufacturing environment. • The bioburden of a product can vary depending on the number of sources of contamination. The purpose of bioburden testing is to measure the number of bacteria present in a product. This can help to ensure the product is safe and meets the quality standards set by the company. Correctly testing and effective quality control are essential to minimize risks for consumers and meet production requirements. • Therefore, bioburden analysis is often included in product testing to ensure the safety, quality and regulatory compliance of each batch. Bioburdentesting is done to measure the amount of chemicals and other pollutants in a product. Following any of the standard methods described below, it is important to ensure that the testing method does not introduce bacteria into the test sample or kill bacteria in the test sample.

3. How Bioburden Testing is Done? The bioburden test is used to identify problems in the manufacturing process that may lead to an inadequate sterilization. The purpose of bioburden testing is to ensure that the drug or medical product is safe and effective for use. In order to ensure that a medical product is safe, it is often necessary to test it for the presence of micro-organisms. Bioburden testing is used to determine the number of pollutants present in a sample. Once the bioburden testing is complete and has been validated, the correct method of removal will be used.

4. Removal methods in Bio-Burden Testing: Following are the methods for the Bioburden testing. • Incubation • Enumeration • Validation The validation process determines the best method. The process that is used to remove bacteria includes the following methods: • Use of the ultra sonication rays • Shaking to remove the germs • Vortex mixing • Blending of the material. • The bioburden of a product is an important part of quality control and determining the overall bioburden of a product.

5. Direct Plating Method: Direct plating method for bioburden testing include pour plate and spread plate. • Pour Plate The pour plate method is more accurate than the other methods. The pour plate method is a method used to culture and test bacteria. The culture medium is added to a petri dish, and the solidified medium is allowed to form. The sample is added to a petri dish with solidified culture media. After the sample has been added to the culture system, the plate is incubated and the culture is enumerated. • Spread Plate This is the method of choice for products that contain antibacterial substances. This method uses a membrane filter to remove the sample. The most commonly used pore size is about 0.45 µm. The membrane functions as a barrier and captures microorganisms larger than the membrane pore size. A vacuum can be used to reduce the time taken for filtration. This can be useful in some cases as it can help to speed up the process. The membrane is transferred from culture media to a cold incubator for at least 5 days to allow bacteria and fungi to grow and detect each other. The resulting culture determines the levels of microbial contamination in the sample. There needs to be a way to avoid any cross- contamination that could lead to false-positive results.

6. Why is Biocompatibility Testing Important? Biocompatibility testing is used to measure the compatibility of medical devices with biological systems to ensure that they are not toxic or injurious and not causing immune rejection when used in combination with living tissue or a living system. The test results help to determine the potential toxicity of a material or medical device, as well as evaluate local and systemic reactions. The importance of biocompatibility testing is the evaluation of the effects of interaction between medical devices and the tissues and physiological systems of the patient treated with the devices. Animal models are used to test analytical chemistry products. In-vitro tests are used to test the effectiveness of these products.

7. Use of Biosynthetic Materials: The clinical use of biomaterials must be compatible with the body’s natural cells and tissues. Biosynthetic materials are able to perform their function without causing any harm to biological systems, but can produce a specific response in a specific case. Today’s biocompatibility concept includes following aspects: • Bio-Inertia • Bio Functionality • Bio Stability. • The high biocompatibility and functional properties of a new biomaterial are desired. Biological materials can have a significant impact on the biocompatibility of a material. • There are several factors that influence biocompatibility, for instance • The chemical and physical nature of the component materials; • Types of patient tissue that will be exposed to the devices; • The duration of the exposure to germs. Testing is important because the presence of extractable chemicals and agents from the processing may affect the biocompatibility of a biological system, which can affect the whole system.

8. Cytotoxicity Testing: Cytotoxicity testing is one of the tests used to evaluate the potential toxicity of chemicals. Medical devices that are contact with material may not be able to be used safely. Since the individual materials used to make the medical device may be biocompatible, but the combination of various materials may cause a toxic reaction. The device needs to be evaluated for biocompatibility in order to be effective. Following methods are using during this testing: • severe systemic toxicity, • biodegradation, • carcinogenicity, • continuing toxicity, • hemocompatibility, • imbedding, • intra-cutaneous irritation, • sensitization, • sub chronic toxicity. Besides the conventional methods , there are two other methods that are usually used in biocompatibility testing. • In-Vitro Testing • In-Vivo Testing.

9. In-Vitro Testing: In-vitro testing is done outside of a living organism, whereas in-vivo testing is done inside of a living organism. Cytotoxicity is used to measure the toxicity of materials and chemicals in cultured cells. In-Vivo Testing: In-vivo Bioburden testing is conducted after the completion of in-vitro testing. The type of testing that is done on a device depends upon the device’s intended use. Various tests are performed in vivo to check the effects of chemicals on the body. These tests include: • skin irritation testing, • sensitization testing, • implantation testing, and • systemic toxicity testing. These tests can take a lot of time to complete, depending on the data that’s needed. Source: https://insiderforge.com/importance-of-bioburden-and-biocompatibility-testing/