Selective and sensitive detection of metal ions by plasmonic resonance energy transfer-based nanospectroscopy

Abstract

Highly selective and sensitive optical methods for the detection of metal ions have had a substantial impact on molecular biology, environmental monitoring and other areas of research. Here we demonstrate a new method for detecting metal ions that is based on selective plasmonic resonance energy transfer (PRET) between conjugated metal-ligand complexes and a single gold nanoplasmonic probe. In addition to offering high spatial resolution due to the small size of the probe, our method is 100 to 1,000 times more sensitive than organic reporter-based methods. Moreover, it can achieve high selectivity owing to the selective formation of Cu(2+) complexes and selective resonant quenching of the gold nanoplasmonic probe by the conjugated complexes. We expect that PRET-based metal ion sensing could have applications in cellular imaging, systems biology and environmental monitoring.

Surface Patterning with Colloidal Monolayers

“…Fluorescence enhancement [260] or plasmonmediated Förster resonance energy transfer [261] could be investigated by addressing the gaps with fluorophores. Moreover, the presented double crescents possess dark modes as well, i.e.…”

Metal-organic charge transfer can produce biradical states and is mediated by conical intersections

“…A third minimum (iii) at shorter distances along the same path corresponding to a closed-shell state with molecular orbital structure ϕ 2 2 has also been found; however, it does not necessarily represent the ground state at a given Ca⋯C distance in all three systems. The topography of the lowest adiabatic singlet potential energy surface is due to the one-and two-electron bonding patterns in Ca-π complexes.metal atom | metastable state | nature of metal-π binding | one-and two-electron multicentered bonds | triplet ground state T he interactions of metal atoms with alkenes, polyenes, aromatics, and graphene-based materials are important for applications in catalysis (1, 2), molecular electronics (3-6), optoelectronic and sensing devices (7,8), and hydrogen storage materials (9-12). Charge transfer from the metal to the organic system is one of the key features determining adsorption energies, reactivities, electronic structure, conductivities, and optical properties (4,8).…”

“…Charge transfer from the metal to the organic system is one of the key features determining adsorption energies, reactivities, electronic structure, conductivities, and optical properties (4,8). Most studies of charge transfer have focused on equilibrium geometries (4, 13-15), but the design of molecular devices and the understanding of adsorption and reactivity also require understanding the dependence of charge transfer on molecular geometry (16).…”

“…T he interactions of metal atoms with alkenes, polyenes, aromatics, and graphene-based materials are important for applications in catalysis (1,2), molecular electronics (3-6), optoelectronic and sensing devices (7,8), and hydrogen storage materials (9)(10)(11)(12). Charge transfer from the metal to the organic system is one of the key features determining adsorption energies, reactivities, electronic structure, conductivities, and optical properties (4,8).…”

Bioinspired optical antennas: gold plant viruses

“…4,47,48 Because gold viruses have larger optical cross sections than those of similar-sized nanoparticles, they offer enhanced encoding efficiency. To characterize the sensitivity of gold viruses for the encoding of absorption spectra, one type of gold virus was tested for the detection of cyt c. 4,47 Various concentrations of cyt c were incubated with CPMVs coated with 5 nm of gold, and as a control, gold-coated nanospheres (33-nmdiameter polystyrene beads) were simultaneously examined.…”