Abstrato

Synthesis and physicochemical studies on 4-methylpiperazine-1- carbodithioic acid capped silver nanoparticles

Shashi Bala Kalia, Monika Bharti, Manjeet Sharma

Stable silver nanoparticles were synthesized with a passivating monolayer of 4-methylpiperazine-1-carbodithioic acid (4-MPipzcdtH) - derivative of heterocyclic amine, 1-methylpiperazine (1-MPipz). Particles were characterized by elemental analysis and energy dispersive analysis of X-rays (EDAX). SEMimages of powdered sample revealed spherical shape. Core diameter of resulting nanoparticles was determined to lie in 3-5 nm range using transmission electron microscopy (TEM). 1H NMR and IR spectroscopy studies were used to check the particle purity. XRD patterns indicated arrangement of silver nanoparticles with a face centered cubic (fcc) structure. Surface plasmon resonance peak has been observed at 430 nm. Paramagnetic nature of particles (µeff=1.74 B.M.) supports reduction of silver (É) to silver (0). Lipase activity assay of capped silver nanoparticles with different core diameters exhibited reduction in activity with decreasingmetal feed ratio. Silver (I) complex of 4-MPipzcdtH has also been synthesized and investigated. The results have been compared with those of 4-MPipzcdtH cappedAg nanoparticles.