CINCINNATI, OHIO, July 24, 2023 (PRNewswire) – The Life Science division of Meridian Bioscience, Inc., a leading global provider of diagnostic testing solutions and life science raw materials, announced today the launch of two new immunoassay interference blockers, K-Block™, and Mouse-Free IgG. These innovative blockers are 100% animal-free and have equivalent or superior performance compared to traditional animal-derived blockers. This product launch aligns with Meridian’s strategy to pioneer sustainable and innovative raw materials for diagnostic assay manufacturers. By adopting these animal-free products, manufacturers can actively contribute to reducing their ecological impact by optimizing energy and resource consumption and staying compliant with evolving regulatory standards. Meridian continues to lead the way in promoting environmental responsibility within the industry.

Immunoassay interference can cause false positive and false negative test results, leading to misinterpretation and improper patient diagnosis. The most common causes of interference are due to Human Anti-Mouse Antibodies (HAMA), Rheumatoid Factor (RF), and Heterophilic Antibodies (HA).  HAMA are the most prevalent and are identified in up to 25% of the patient population. Combined with HA, they represent the most significant factors leading to false positive immunoassay results. Avoiding immunoassay interference requires blockers to be included in every immunoassay. Historically, animal-based interference blockers have been used to improve assay accuracy; however, they are susceptible to cross-reactivity with assay reagents, lot-to-lot variability, and supply shortages – as seen during the COVID-19 pandemic.  Meridian’s new animal-free immunoassay interference blockers mitigate those concerns.

Meridian’s new K-Block and Mouse-Free IgG overcome the challenges encountered with traditional animal-based blockers. These next-generation blockers improve assay specificity, decrease lot-to-lot variability, align with sustainability considerations, and alleviate contamination risks from animal-derived components. Initial experimental testing in ELISA-based assays demonstrated strong performance of K-Block and Mouse-FREE IgG versus other commercial animal-derived blockers.


“At Meridian, we are deeply committed to supporting our customers who are seeking non-animal-derived raw materials in diagnostic assays.   Our novel 100% animal-free blockers deliver on this commitment while avoiding the need to consume millions of mice each year in the process. This innovative method not only allows us to scale up quickly but also delivers results that are equivalent or even superior in quality. With this new product line, we reaffirm our dedication to environmental sustainability and social responsibility, ensuring a more ethical and responsible approach in our operations as well as our customers.” commented Lourdes Weltzien, Ph.D., President – Life Science, Meridian Bioscience.

For more information on K-Block or Mouse Free-IgG, please visit

You can learn more about animal-free blockers at the Meridian Bioscience exhibit booth (4039) during this year’s AACC conference held in July in Anaheim, California.  Request a one-on-one meeting with a Meridian representative

About Meridian Bioscience, Inc.

Meridian is a fully integrated life science company that develops, manufactures, markets, and distributes a broad range of innovative diagnostic and life science products. We are dedicated to developing and delivering better solutions that give answers with speed, accuracy, and simplicity that are redefining the possibilities of life from discovery to diagnosis. Through discovery and development, we provide critical life science raw materials used in immunological and molecular tests for human, animal, plant, and environmental applications. Through diagnosis, we provide diagnostic solutions in areas including gastrointestinal and upper respiratory infections and blood lead level testing. We build relationships and provide solutions to hospitals, reference laboratories, research centers, veterinary testing centers, physician offices, diagnostics manufacturers, and biotech companies in more than 70 countries around the world. Meridian is a privately held company headquartered in Cincinnati, Ohio.  Meridian’s website address is



Courtney Schulz

Director of Digital and Corporate Communications

Meridian Bioscience, Inc.

Phone:  513.271.3700