Cell based assays or bioassays are often an integral part of the FDA drug approval process. Our deep expertise includes assays performed with primary cells, commercially available cell lines and transforming cell lines to meet your needs. Whether you have an assay to transfer or are looking to develop an assay from a paper, our specialized experience ensures you the shortest route to a completed assay development, qualification or validation. We are daily practitioners of what we call “The Art of Cell Culture”. Scroll down for more information on some of the more common assays we perform for clients.

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Live cell experiments, the heart of in vitro services

Cell-based assays (bioassays) are used to evaluate a variety of functional biological and biochemical effects, including cell proliferation, apoptosis and necrosis, cell signaling, enzyme assays, gene activation, antibody-dependent cellular cytotoxicity (ADCC, MLR) and complement-dependent cytotoxicity (CDC), among others. These techniques are used to support neutralizing antibody assays, potency assays, receptor binding assays, reporter assays, mechanism of action studies and drug combination analysis, as well as supporting, receptor turnover, subcellular fractionation and localization including immunocytochemistry, metabolic assays, drug delivery, drug metabolism, to name a few. Because live cells are used, functional bioassays are the epitome of determining your drug’s biological activity. A drug can bind with the cell surface, but may not be effective in eliciting an intracellular signaling or function. Cell-based assays provide a functional read-out of compound activity or produce results that are more biologically or physiologically relevant. Our experience with optimizing cell culture medium, serum-free adaptation and cell cloning has beenessential to improve some bioassays. Additionally,we have developed cell lines and cultured primary cells for specific assays, as well as developing methods for isolation and characterization of cell populations.


From the beginning and ongoing, your assay is a critical component of the life cycle of your current or eventual product. That is precisely why you want experience and expertise at the earliest possible stage of your development.

When you need an assay to prove your science and there is no commercial kit available, you need a custom assay. Our extensive expertise will quickly and methodically develop your assay to prepare it for eventual validation. Typically an assay can be developed from scratch in 5 or less experiments while minimizing any matrix effects.

We are firm believers in kits. The analytical portion of the assay itself is only a single component of what it takes to perform a successful experiment. It is all the other skills, experience and GLP/GMP conditions that we do day in and day out that will save you time getting to the results you actually want yesterday. We can create and distribute kits, too.

Many companies planning an IND submission or in Phase I/II may only require a well-qualified assay rather than a fully validated assay. You may or may not need GLP/GMP stringency and auditability yet. Our scientific team works with your scientists to qualify your assay for reproducibility, appropriate precision and accuracy.

To validate an assay is to measure precision, linearity, accuracy, robustness, system suitability and repeatability. To achieve these results, we conduct multiple experiments in a pre-validation phase with the assay. This phase is a series of 2-4 experiments that specifically look at these capabilities. Once we have advanced an assay, we perform the assay 2 more times for a total of 3 identical repeats. At that point, your assay meets the FDA GLP or GMP requirements.

Whether patient samples or drug product samples we will map out a timeline and follow through with sample receipts, meeting your regulatory needs at all points. We perform your assay as developed, qualified or validated, and promptly communicate the results and/or Certificate of Testing for any or all of your preclinical or clinical phases.

Knowing the importance to the FDA of lot release potency testing, our scientific team tests every manufacturing lot with your assay providing Certificates of Testing in a timely manner, under GMP Condition.

In order to determine shelf life for a particular drug substance, stability tests are performed at pre-determined calendar intervals. Our project coordinators communicate closely with you to anticipate the arrival of samples so as to have our staff and resources available for timely analysis and submittal of data and Certificates of Testing.


The complexity involved in cell analysis demands an advanced level of bioanalytical skill, cell culture experience and knowledge for the assay itself and the FDA regulatory parameters an assay must uphold. With our veteran scientific staff averaging 15+ years of experience developing and performing cell based assays, we have developed a comprehensive and rapid approach to working out the intricacies of a cell based assay.

What is “The Art of Cell Culture”?