We report the development of highly versatile fluorescent and photostable core−shell Ag@SiO2 nanocomposites, which allows researchers flexibility to incorporate just about any fluorophores outer silica shell by two simple methods. To show generality preparation technique, we have developed three different probes: an organic fluorophore (Rh800) a lanthanide probe doped (noncovalently linked) (Alexa 647) covalently linked shell. When compared control nanoparticles (nanobubbles), with silver...

The effects of thermally annealed silver island films have been studied with regard to their potential applicability in applications metal-enhanced fluorescence, an emerging tool nano-biotechnology. Silver were between 75 and 250°C for several hours. As a function both time annealing temperature, the surface plasmon band at ≈420 nm diminished was blue shifted. These changes resonance characterized using absorption measurements, as well topographically Atomic Force Microscopy. Subsequently,...

A simple and rapid wet-chemical technique for the deposition of silver triangles on conventional glass substrates, which alleviates need lithography, has been developed. The is based seed-mediated cetyltrimethylammonium-bromide-directed growth surfaces, where smaller spherical seeds that were attached to surface subsequently converted grown into in presence a cationic surfactant ions. size was controlled by sequential immersion seed-coated substrates solution duration time immersion. Atomic...

Two methods have been considered for the deposition of silver nanorods onto conventional glass substrates. In first method, were deposited 3-(aminopropyl)triethoxysilane-coated substrates simply by immersing into nanorod solution. second spherical seeds that chemically attached to surface subsequently converted and grown in presence a cationic surfactant ions. The size was controlled sequential immersion seed-coated growth solution duration immersion, ranging from tens nanometers few...

Surface modification of colloidal gold with 11-mercaptoundecanoic acid or 16-mercaptohexadecanoic was performed in the absence presence nonionic surfactant polyoxyethylene (20) sorbitan monolaurate (Tween 20). The stability systems assessed optical absorption spectroscopy. surface-modified nanoparticles were stable only within a narrow range intermediate pH values when chemisorption alkanethiols Tween 20. This explained terms partial ionization surface carboxylic groups and charge...

In this article, we report metal-enhanced singlet oxygen generation (ME 1 O 2 ). We demonstrate a direct relationship between the yield of common photosensitizer (Rose Bengal) and theoretical electric field enhancement or enhanced absorption in proximity to metallic nanoparticles. Using series photosensitizers, sandwiched silver island films (SiFs), that extent is inversely proportional free space quantum yield. By modifying plasmon coupling parameters, such as nanoparticle size shape,...

In this communication, we present the proof-of-principle of a new RNA sensing technique, based on metal-enhanced fluorescence, which may improve potential solid substrate-based capture assays. regard, detection is accomplished by annealing target tagged with fluorophore to DNA anchor probe in single step surface, where fluorescence signal enhanced silver nanoparticles. Furthermore, proposed method highly amenable high-throughput screening applications and capable detecting less than 25 fmol...

Biotinylated gold nanoparticles were prepared by using a two-step surface modification procedure. First, carboxyl-terminated alkanethiol was chemisorbed onto the of in presence stabilizing agent. Subsequently, carboxyl groups reacted with (+)-biotinyl-3,6,9,-trioxaundecanediamine and 2-(2-aminoethoxy)ethanol. This procedure resulted stable, ligand-modified nanoparticles. Upon interaction streptavidin, biotinylated aggregated means specific biomolecular recognition. Their aggregation studied...

Gold colloids are well known to display strong plasmon absorption bands due electron oscillations induced by the incident light. When in proximity, often perturbed. This has enabled us recently successfully develop a glucose sensing platform based on disassociation of dextran-coated gold colloids, cross-linked with Con A, glucose. However, much more useful and simpler property which been ill explored regard sensing, is their ability efficiently scatter excitation We have found that our...

In this letter, the authors report observation of metal-enhanced fluorescence emission from fluorophores deposited on copper (Cu) substrates. Different thicknesses Cu particulate films (from 1 to 5nm) were onto glass slides using thermal vapor deposition. Fluorophores positioned in close proximity show enhancement as a function thickness increases, reaching maximum (2.5-fold) at ≈3nm. The findings strongly suggest that surface plasmons can radiate and therefore enhance fluorophore’s spectral...

We describe an exciting assay platform technology that promises to fundamentally address two underlying physical constraints of modern assays and immunoassays, namely, sensitivity rapidity. By combining the use metal-enhanced fluorescence with low-power microwave heating, we can indeed significantly increase surface as well >95 % kinetically complete within a few seconds. Subsequently, this new change way currently employ immunoassays in clinical medicine. This model system be potentially...

Silver nanoparticles were deposited onto polycarbonate (PC) films by employing sequential surface modification methods. In the first step, PC etched either exposure to ultra-violet radiation or etching with sodium hydroxide at 70 °C, which resulted in formation of a mixture hydroxyl and carboxyl groups on films. Next, silanized 3-(aminopropyl) triethoxysilane (APS) order introduce amine terminal surface. Lastly, silver APS-modified films, occurred due well-known affinity towards groups....

We describe an exciting opportunity for affinity biosensing using a ratiometric approach to the angular-dependent light scattering from bioactivated and subsequently aggregated noble metal colloids. This new model sensing platform utilizes changes in particle very small colloids, which scatter according traditional Rayleigh theory, as compared observed by much larger colloidal aggregates, formed due bioaffinity reaction. These aggregates no longer incident Cos2 θ dependence, is case...

We report our detailed metal-enhanced phosphorescence (MEP) findings using Rose Bengal at low temperature. Silver Island Films (SiFs) in close proximity to significantly enhance the emission intensity. In this regard, a 5-fold brighter intensity of was observed from SiFs as compared glass control sample 77 K. addition, several factors affecting MEP, such distance dependence and silver film morphology, were also investigated. Our suggest that both singlet triplet states can couple surface...