A sensor may include a membrane to deflect in response to a change in surface stress, where a layer on the membrane is to couple one or more probe molecules with the membrane. The membrane may deflect when a target molecule reacts with one or more probe molecules.
STATEMENT OF GOVERNMENT-SPONSORED RESEARCH
 This invention was made with Government support under Grant (Contract) No. R21 CA86132-01 awarded by the National Institutes of Health/National Cancer Institute and Contract No. DE-FG03-98ER14870 awarded by the United States Department of Energy. The Government has certain rights in this invention.