ABSTRACT
Nanoparticle (NP) shape has a profound effect on many properties of nanomaterials, including their optical, electrical, and magnetic properties. The synthesis of CdSe NPs of controlled morphology was achieved by injection of a tri-alkyl phosphine solution of dimethyl cadmium and selenium powder into hot trioctyl phosphine oxide with addition of hexyl phosphonic acid. Particle geometry also has implications for the properties of semiconductor NPs. Elongated magnetic NPs display an anisotropic response to a magnetic field. Gold NPs of different shapes were prepared by seed mediated synthesis, then coated in gelatine to improve their biocompatibility. NPs can accumulate in tumours and thus be used for the delivery of contrast agents or drugs. NPs which are coated with cell-membrane receptor-specific ligands can bind to their target receptors and induce signal cascades within the cell without actually being internalised.
