Signature: Molecular voyeur

Among the methods used to describe the structures of complex molecules such as proteins, none is capable of assessing the structure or changes in structure of molecules interacting in a natural environment such as water or saline. Techniques like x-ray crystallography provide only a frozen snapshot of a protein, revealing limited information about the protein's function. Signature BioScience Inc. believes it has found a way to watch molecules as they interact in physiological environments by capitalizing on an existing property of all molecules: their charge.

Every molecule has a characteristic set of electrical charges based on its structure and atomic makeup. Signature's technology uses a form of microwave spectroscopy. When a molecule is placed in an electromagnetic field of a specific frequency, it absorbs a certain amount of energy and reflects a certain amount depending on the distribution of its charges and the atomic bonds that hold it together. Spectroscopy can sense the pattern of absorption and reflection as a unique signal...