By helping to identify the proteins involved in fundamental cellular reactions, protein chips could become powerful aids in disease diagnosis. Aspira Biosystems, a startup in South San Francisco, CA, has developed a way to make protein chips that are more reliable and can detect more proteins than existing chips. Most of today’s protein chips rely on nanoscopic spots of special proteins to interact with and capture other proteins. Because the molecules are so finicky, however, chips are available for only a few types of proteins. Aspira’s system lets researchers make casts of short fragments of proteins in a polymer; these casts, arrayed on a chip, can selectively capture the matching proteins from a mixture of molecules. Using this technique, it should be possible to make chips that can latch onto virtually any protein, making way for the diagnostic tests that are needed to make personalized medicine a reality. Next year Aspira plans to begin selling the chips to pharmaceutical and biotechnology companies for use in drug discovery; diagnostic applications will follow.