We propose extending magnetoelastic sensor technology from the microscale to the nanoscale. This scaling of dimensions will enable the resultant sensor arrays to be placed within tube sidewalls, providing physical and chemical information of the tube interior (air or liquid) without interference of flow characteristics. Device sensitivity on the nanoscale should enable the instantaneous detection of single molecule binding events. The remote query nature of the sensor technology enables sensor information to be transmitted from the interior of the tube without the use of physical connections, avoiding possible contamination. Since the sensors transmit information via magnetic flux they are not susceptible to interference affects that might affect optical sensors, e.g. moisture condensation, smudges, misalignment, etc. Combining the best features of nanowire device fabrication and magnetoelastic sensor technology, the sensors should be able to distinguish mass changes of femto-grams but yet be inexpensive enough to be readily used on a disposable basis. It is anticipated that such sensors would find immediate application in clinical care, in effect creating a 'smart tube' technology. In Phase I, we will fabricate ordered magnetoelastic nanowire cantilever arrays, as described herein, of 1, 5, 10, and 50 cantilevers. Initially we will modify and extend the needed measurement electronics to monitor these uncoated nanocantilevers in air and liquid establishing baseline signal-to-noise values as a function of nanowire composition, properties and dimensions. The nanocantilevers will then be coated with a polymer of precisely controlled thickness, in incremental steps of less than 2 nm, to establish baseline sensitivity values and operating characteristics. In Phase II, the nanocantilevers will be coated with analyte specific layers and integrated with disposable tubes enabling their use as clinically relevant analyte and environmental sensors for, initially, neonatal monitoring.
