Biotin is a very hydrophobic molecule. Based on our experience, antibodies and proteins labeled with biotin tend to aggregate and precipitate out from solution over time. In the past, for optimized performance, we have controlled all antibody and protein biotin labeling to 2-4 biotin per antibody/protein. However, in many cases, high loading of biotin is desirable for an enhanced/amplified signal or selection. We have modified biotin with AqT® linker to increase biotin’s hydrophilicity. The hydroxy (-OH) groups of AqT® linkers create a microenvironment that shields neighboring biotins from stacking or interacting with one another. Antibody/protein can be labeled with a high amount of AqT®-biotin without change its properties. CellMosaic is currently developing AqT® biotin labeling kits and products. If you are interested in using such products or co-developing AqT® biotin-based products, please let us know.
For a detailed description of the AqT® technologies, please see our technology section.