Abstract: Nanoparticle sized metal or alloy is synthesized through a reverse micelle system which includes the steps of a) forming a concentrated aqueous solution of transition metal salts with platinum salts b) dispersing the metal salt solution in a non aqueous solution of a surfactant c) adding a reducing agent to reduce the metal salts to metallic alloy nano-particles in the absence of oxygen d) separating the metallic alloy nanoparticles 1s) heating the metallic alloy nanoparticles under controlled time, atmosphere and temperature conditions sufficient to form particles of a desired size and magnetic characteristics. The, precipitated metal or alloy nanoparticle has an average size of 3 nm and is superparamagnetic. Through controlled annealing treatment, the magnetic characteristics of the nanoparticles can be manipulated to achieve specific values in the final product that is suitable for predetermined applications. The nanoparticles exhibiting superparamagnetism are suitable for magnetic bio-bead applications.

Abstract: A surface acoustic wave sensor is provided having a piezoelectric material deposited on a piezoelectric substrate. The preferred structure is zinc oxide on ST-cut quartz crystals that allows propagation of a Love mode acoustic wave end is particularly useful in liquid media as well as gas. The sensor can be used to detect biological or chemical moieties.