Formation of nanoparticles of sparingly soluble salts (caso4 and caso4:dy) using liquid-liquid separation method and application for detection of α-radiations

This is one of the first reports to demonstrate the formation of nanosize particles (radius of 75-150 nm) of a sparingly soluble salt, calcium sulphate (CaSO₄), using the liquid-liquid separation method. First, the monomer reservoir of nuclei is formed by reacting Ca-salt of dodecyl sulphate in ethylene glycol with sulphuric acid. Secondly, ethanol (i.e. a poor solvent) is added drop by drop to the monomer reservoir under constant stirring to precipitate CaSO₄ (or CaSO₄:Dy) particles. The concentration of the surfactant (SDS), which forms the Ca-salt of dodecyl sulphate, helps to control the size of the nanoparticles. The 75-nm CaSO₄ :Dy particles thus formed are useful for the detection of alpha-radiations