Structural studies and in vitro cytotoxic activity of dodecylamine passivated palladium sulfide and ruthenium sulfide quantum dots

Dodecylamine capped palladium sulfide (PdS-DDA) and ruthenium sulfide (RuS-DDA) nanoparticles were synthesized from bis(piperidinedithiocarbamato)palladium(II) and tris(piperidinedithiocarbamato)ruthenium(III). The optical band gaps were 4.34 eV for PdSDDA and 3.63 eV for RuS-DDA nanoparticles. The PdS-DDA corresponds to tetragonalPdS while RuS-DDA have cubic crystalline phase. The PdS-DDA nanoparticles were monodispersed with particle sizes of 3.15-5.63 nm while the RuS-DDA nanoparticles had particle sizes of 1.18-1.75 nm. Anticancer screening revealed PdS-DDA nanoparticles have better cytotoxicity with IC50 of 10.02 μg/mL against HEK293 and 38.89 μg/mL against HeLa in comparison to about 90.02 μg/mL for RuS-DDA nanoparticles against both cells.