The Eagle Biosciences ELISA for mouse/rat IGF-I E25 is a so-called Sandwich-Assay. It utilizes two specific and high affinity antibodies for this protein. The IGF-I in the sample binds to the immobilized first antibody on the microtiter plate, the biotinylated and Streptavidin-Peroxidase conjugated second specific anti-IGF-I-Antibody binds in turn to the immobilized IGF-I. In the closing substrate reaction the turn of the colour will be high specific catalysed, quantitatively depending on the IGF-I-level of the samples. Sample Types: serum, plasma. Range: 0.5 - 18 ng/mL. Sensitivity: 0.029 ng/ml. Time: 2 hours ? Beside different cell culture models and studies with human patients, mice and rats are suitable model organisms for basic research and pre-clinical studies.Thus, we developed this test system as a tool for IGF-I measurements in mice and rat for usage in research and pre-clinical studies. Even if the comparability of mice and humans is limited we offer some background information on the human IGF-I system in the following section: