Chiral imprinting in molten gallium

Ultrasonic irradiation of molten gallium in warm water produces micro- and nanoparticles of gallium. Doing it in aqueous solution of organic compounds results in encapsulation of the molecules within the particles and imprinting on their surface. Sonication of molten gallium in aqueous solutions of D- or L-tryptophan, followed by leaching of the enantiomer in pure water, leaves molecular templates on the surface of the gallium particles. These particles can then entrap the specific enantiomer from a solution of the racemate, yielding an enantiomeric excess of 6–12%. The extent of the enantiomeric excess was determined using polarimetry, chiral HPLC and circular dichroism measurements.