Studies using radioisotopes have been used for decades because they offer extremely high sensitivity. The methods have universal application for protein characterization and protein quantitation, binding assays, DNA/RNA receptor binding, cell-based assays and other uses.

Marin Biologic Laboratories Speak to a Scientist

Speak to a Scientist

We believe the best way to learn your needs is via a real time conversation. We always prefer to start with a discussion to assist you in meeting your goals. Click the orange button and we’ll get right back to you.

speak to a scientist

Direct measurements without bulky tags

The advantage of radioimmunoassays (RIA) is that no large bulky tag is needed, which can influence the assay. Common uses of radioactivity are for DNA detection and size, RNA detection (radiolabeled during synthesis or by a tag), radioimmunoassays for proteins or small molecules, enzyme activity, binding affinity to receptors, membranes and cells, and intracellular localization of a compound. Radioimmuno assays are often the assay of choice to develop and perform cell proliferation, enzyme activity, binding affinity, intracellular localization, detecting DNA or RNA by southern and northern blot, and binding to proteins by various methods, and of course, RIAs for quantification.


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.

Your Results without regulatory and licensing hassles

Marin Biologic has the specialized instrumentation, monitoring and disposal licenses for multiple isotopes which are required for these types of tests. We will gladly discuss the pros and cons of using a radioactivity assay. Our staff is highly trained and employs safe handling of isotopes so that your organization will not need to undergo the governmental regulation required for these assays.

We are currently licensed for these isotopes: 3H for labeled tymindine update into DNA, 32P for various nuleic acid assays, 14C and 35S for amino acid and protein studies,, 45Ca for metabolism studies, 51Cr for target killing tests and 125I for radiolabeling proteins.