Silver Nanoparticles Enhanced Luminescence of Terbium Complex in Solution for L-Dopa Determination

Abstract

Luminescent properties of a terbium (Tb3+)-L-3, 4-dihydroxyphenylalanine (L-dopa) complex by binding to colloidal silver nanoparticles (Ag NPs) have been presented. Luminescence intensity of the L-dopa complex was dramatically enhanced about 6-7 times by introducing Ag NPs. The Ag NPs concentration on the luminescent intensity was regarded as a main factor that balancing between an enhancing and a quenching effect of the Ag NPs. It was observed that changing the concentration of L-dopa causes the change in luminescence intensity. Under the optimized condition, the luminescence intensity of the system was linearly related to the concentration of L-dopa. Based on this observation, L-dopa-Tb3+ complex containing Ag NPs has been applied for the determination of L-dopa in pharmaceutical formulation. Linear responses of luminescence intensity were observed in the concentration range of 0.25 to 1.5 nM (r = 0.9934) of L-dopa with limit of detection 0.042 nM. The performance of the system was tested using 1.0 x 10(-9) M of L-dopa, yielding a precision of 1.21% RSD for nine replicate measurements. The present method has been successfully applied to determine L-dopa in pharmaceutical samples.

Improved fluorescence properties of core–sheath electrospun nanofibers sensitized by silver nanoparticles

“…Recent studies found that some precious metal nanoparticles (e.g., silver (Ag), gold (Au)) can influence the fluorescence properties of RE complexes on account of the localized surface plasmon resonance (LSPR) effect of the precious metal nanoparticles [11][12][13][14][15][16]. LSPR arises from the resonant oscillation of conduction electrons on the surface of metal nanoparticles.…”