Sorex Sensors Limited is a new spin-out from Cambridge University Engineering Department, looking to manufacture world-leading, highly-sensitive mass sensors which can measure down to femtograms, the weight of a single virus particle. The devices are very small (each is ~100 µm across), have extremely low power requirements (in the order of µW) and can be fabricated on silicon wafer using standard foundry processes. Uniquely, the sensors can measure both mass and temperature simultaneously providing significant advantages over existing mass-measurement technologies. Applications that require accurate measurements and the ability to multiplex are being pursued in vacuum-based deposition process control, gas monitoring and particulate monitoring markets.