Of the particular uses for nanotechnological sensors, gas sensors make up the largest fraction, with similar prevalence of journal and patent publications. Detection of gases may allow detection of analytes while avoiding solvent or mass transfer effects existing in solution. Nanosensors may allow the detection of gases with lower spatial resolution or in biological systems. Nanoscale sensors may reduce the costs of gas sensing or increase its sensitivity and thus improve safety. For example, detection of H2S, 147 CO, 148 and NO2 149 using nanosensors has been a topic of interest. As for gas sensors, electrochemical sensors using nanomaterials may provide advantages because of feature size and fundamental mechanistic knowledge, while a variety of stimuli can be detected electrochemically. Surface plasmon resonance (SPR)-based sensors and immunosensors make up the largest fractions of sensors for biological applications. SPR can be used to detect a variety of binding events and to determine binding constants, making it useful in understanding and detecting biological events. The prevalence of gold in sensors is consistent with the use of gold surfaces for SPR; detection of plasmons in gold nanoparticles might improve sensitivity and allow use on smaller scales or to render them more convenient. Immunosensors are important diagnostic tools; the ability to reduce their scale could either be used to reduce the cost of diagnostics, or to perform many tests at once, allowing testing of many cells and determining the behaviors of individual cells or to detect many immunomolecules (and perhaps disease states) at once. Temperature sensors have received significant interest in patents, though nearly as much interest in journal publication. Temperature nanosensors are useful in manufacturing because they allow temperature monitoring on smaller scales and thus may allow improvements in temperature control in industrial processes. Glucose, pressure, and enzymic sensors are less explored on nanoscale. Glucose concentration and pressure are likely quantities relevant on macroscopic scales; the market for glucose sensing may also be mature and thus difficult to enter or to demonstrate superiority or reduced cost.