Embedded radiometry system for biomedical applications via thermal diffusivity properties

A Radiometry Photothermal Infrared technique, by using a calibrated scanning depth profile, for biomedical applications is described. The instrument, consists of a pulsed medium-power laser (500 mw), collected and focused onto an infrared detector after impinging on the sample, by using a look-in amplifier, thereby obtaining the amplitude and phase of the modulated signal, collected by an embedded system. The system was tested by using Ag nanoparticles (average diameter 10 to 30 nm), obtained by chemical reduction of AgNO3, at concentrations of 1, 0.5, 0.25, 0.125 and 0.062 % in water.