With respect to materials nanosensors appear to be associated most commonly with organic and inorganic substances, particularly titanium, silicon, and zinc oxides, as well as elements such as carbon, gold, and silicon to a lesser extent. Small molecules such as glucose, H2O2, ethanol, and ammonia are frequently associated with sensors, and all are important analytes in biological systems. The other major class of substance important in the context of nanosensors are polymers with specific examples including PEG and PANI likely to control nonspecific protein absorption and for conditional conductivity, respectively.