Counting single Rhodamine 6G dye molecules in organosilicate nanoparticles

Trenkmann, Ines; Bok, Sangho; Korampally, Venumadhav; Gangopadhyay, Shubhra; Graaf, Harald; Borczyskowski, C. von

doi:10.1016/j.chemphys.2012.02.014

Cited by 14 publications

(16 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here, enhancement factor is estimated as a ratio of R6G fluorescence intensities for gold PN with SiO 2 shell and bare glass substrate near maximum emission wavelength (548 nm). Small blue-shift of R6G emission with respect to tabular value can be explained by presence of silicon oxide shell near the dye, which changes the dielectric environment of R6G [36]. It is of importance that the enhanced signal was observed only if the proximity of wavelengths of PN LSPR, dye emission and dye excitation has been provided, which is in agreement with well-known phenomenon of emission enhancement by strong electric field generated by PN under LSPR conditions [37].…”

Section: Resultssupporting

confidence: 73%

Plasmon-enhanced fluorometry based on gold nanostructure arrays. Method and device

Chegel¹

2015

Semicond. Phys. Quantum Electron. Optoelectron.

View full text Add to dashboard Cite

Abstract. In this work, we describe a method of surface-enhanced fluorometry, based on the phenomenon of localized surface plasmon resonance in unordered gold nanostructure arrays. The theoretical approach for the model system "gold nanoparticle-dielectric spacer" in the electrostatic approximation by solution of Laplace's equation is considered. The developed technology for manufacturing the plasmonic substrates as well as design of the novel laser-based compact fluorometer are presented. The arrays of gold nanostructures on solid substrates (nanochips) coated with different thicknesses of SiO 2 were developed and fabricated by thermal annealing of gold island films with subsequent dielectric spacer deposition. As an example for verification of the proposed method, the fluorescence properties of the system "gold nanostructures array -SiO 2 dielectric coating -Rhodamine 6G" were studied. It has been shown that enhancement of dye emission up to 22 times for dielectric coating with the thickness of about 20 nm is possible. Presented method is of importance for the development of the novel nanoscale sensors, biomolecular assays and nanoplasmonic devices.

show abstract

Section: Resultssupporting

confidence: 73%

Plasmon-enhanced fluorometry based on gold nanostructure arrays. Method and device

Chegel¹

2015

Semicond. Phys. Quantum Electron. Optoelectron.

View full text Add to dashboard Cite

show abstract

“…On the other hand, the R6G fluorescence lifetime, the value of which usually varies around 4 ns [63], is known to be highly concentration-dependent, as Förster energy transfer between monomers and weakly fluorescent stable dimers at higher R6G concentrations decreases the quantum yield and causes the fluorescence lifetime shortening [64]. Therefore, a decrease of fluorescence lifetimes in the gel with the highest ALG content may be assigned to a change in the spatial distribution of R6G molecules in the gel, which does not alter the rotational freedom significantly but causes colocalization of R6G molecules and the formation of R6G dimers.…”

Section: Transport Properties Of the Gelsmentioning

confidence: 99%

Multiscale Experimental Evaluation of Agarose-Based Semi-Interpenetrating Polymer Network Hydrogels as Materials with Tunable Rheological and Transport Performance

et al. 2020

View full text Add to dashboard Cite

This study introduces an original concept in the development of hydrogel materials for controlled release of charged organic compounds based on semi-interpenetrating polymer networks composed by an inert gel-forming polymer component and interpenetrating linear polyelectrolyte with specific binding affinity towards the carried active compound. As it is experimentally illustrated on the prototype hydrogels prepared from agarose interpenetrated by poly(styrene sulfonate) (PSS) and alginate (ALG), respectively, the main benefit brought by this concept is represented by the ability to tune the mechanical and transport performance of the material independently via manipulating the relative content of the two structural components. A unique analytical methodology is proposed to provide complex insight into composition–structure–performance relationships in the hydrogel material combining methods of analysis on the macroscopic scale, but also in the specific microcosms of the gel network. Rheological analysis has confirmed that the complex modulus of the gels can be adjusted in a wide range by the gelling component (agarose) with negligible effect of the interpenetrating component (PSS or ALG). On the other hand, the content of PSS as low as 0.01 wt.% of the gel resulted in a more than 10-fold decrease of diffusivity of model-charged organic solute (Rhodamine 6G).

show abstract

“…For homogeneous diffusion processes the distribution of diffusivities is independent of the time lag τ , whereas for heterogeneous systems a non-trivial τ -dependence is observed. Therefore in analyzing heterogeneous systems the distribution of diffusivities provides advantages over an analysis via mean squared displacements (msd) because in addition to its mean value it contains all information about the fluctuations [16]. Furthermore, quantities such as the mean diffusion coefficient, obtained as the first moment of the distribution of diffusivities, are well defined, and thus time-dependent diffusion coefficients and their fluctuations can be calculated.…”

Section: Introductionmentioning

confidence: 99%

How to compare diffusion processes assessed by single-particle tracking and pulsed field gradient nuclear magnetic resonance

Bauer

Valiullin

Radons

et al. 2011

The Journal of Chemical Physics

View full text Add to dashboard Cite

Heterogeneous diffusion processes occur in many different fields such as transport in living cells or diffusion in porous media. A characterization of the transport parameters of such processes can be achieved by ensemble-based methods, such as pulsed field gradient nuclear magnetic resonance (PFG NMR), or by trajectory-based methods obtained from single-particle tracking (SPT) experiments. In this paper, we study the general relationship between both methods and its application to heterogeneous systems. We derive analytical expressions for the distribution of diffusivities from SPT and further relate it to NMR spin-echo diffusion attenuation functions. To exemplify the applicability of this approach, we employ a well-established two-region exchange model, which has widely been used in the context of PFG NMR studies of multiphase systems subjected to interphase molecular exchange processes. This type of systems, which can also describe a layered liquid with layer-dependent self-diffusion coefficients, has also recently gained attention in SPT experiments. We reformulate the results of the two-region exchange model in terms of SPT-observables and compare its predictions to that obtained using the exact transformation which we derived.

show abstract

Counting single Rhodamine 6G dye molecules in organosilicate nanoparticles

Cited by 14 publications

References 22 publications

Plasmon-enhanced fluorometry based on gold nanostructure arrays. Method and device

Plasmon-enhanced fluorometry based on gold nanostructure arrays. Method and device

Multiscale Experimental Evaluation of Agarose-Based Semi-Interpenetrating Polymer Network Hydrogels as Materials with Tunable Rheological and Transport Performance

How to compare diffusion processes assessed by single-particle tracking and pulsed field gradient nuclear magnetic resonance

Contact Info

Product

Resources

About