Time resolved chromatograms in ultra-thin layer chromatography

Oko, A.J.; Jim, Steven R.; Taschuk, Michael T.; Brett, Michael

doi:10.1016/j.chroma.2012.05.090

Cited by 12 publications

(2 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…SCTF as anisotropic filters in ACOM can be used for both imaging and in chemical separations through the use of ultra-thin layer chromatography (UTLC). [108][109][110][111][112][113] In this case, the surface and structure of the SCTF is exploited as a stationary phase 110,114 that could be used for the retention and resolution of applied target analytes. 115 The combination of this chromatographic technique with ACOM permits for the simultaneous separation and detection of targets during their separation on the SCTF support.…”

Section: Acom Observation Of Lipophilic Test Dye Transport In Sctfmentioning

confidence: 99%

Anisotropic contrast optical microscope

Peev

Hofmann

Kananizadeh

et al. 2016

Review of Scientific Instruments

View full text Add to dashboard Cite

An optical microscope is described that reveals contrast in the Mueller matrix images of a thin, transparent, or semi-transparent specimen located within an anisotropic object plane (anisotropic filter). The specimen changes the anisotropy of the filter and thereby produces contrast within the Mueller matrix images. Here we use an anisotropic filter composed of a semi-transparent, nanostructured thin film with sub-wavelength thickness placed within the object plane. The sample is illuminated as in common optical microscopy but the light is modulated in its polarization using combinations of linear polarizers and phase plate (compensator) to control and analyze the state of polarization. Direct generalized ellipsometry data analysis approaches permit extraction of fundamental Mueller matrix object plane images dispensing with the need of Fourier expansion methods. Generalized ellipsometry model approaches are used for quantitative image analyses. These images are obtained from sets of multiple images obtained under various polarizer, analyzer, and compensator settings. Up to 16 independent Mueller matrix images can be obtained, while our current setup is limited to 11 images normalized by the unpolarized intensity. We demonstrate the anisotropic contrast optical microscope by measuring lithographically defined micro-patterned anisotropic filters, and we quantify the adsorption of an organic self-assembled monolayer film onto the anisotropic filter. Comparison with an isotropic glass slide demonstrates the image enhancement obtained by our method over microscopy without the use of an anisotropic filter. In our current instrument, we estimate the limit of detection for organic volumetric mass within the object plane of ≈49 fg within ≈7 × 7 μm object surface area. Compared to a quartz crystal microbalance with dissipation instrumentation, where contemporary limits require a total load of ≈500 pg for detection, the instrumentation demonstrated here improves sensitivity to a total mass required for detection by 4 orders of magnitude. We detail the design and operation principles of the anisotropic contrast optical microscope, and we present further applications to the detection of nanoparticles, to novel approaches for imaging chromatography and to new contrast modalities for observations on living cells.

show abstract

Section: Acom Observation Of Lipophilic Test Dye Transport In Sctfmentioning

confidence: 99%

Anisotropic contrast optical microscope

Peev

Hofmann

Kananizadeh

et al. 2016

Review of Scientific Instruments

View full text Add to dashboard Cite

show abstract

“…In another article [3] the SiO 2 nanopillars were used as scaffolds for functionalization with 2 Journal of Chemistry octadecyltrichlorosilane to generate a superhydrophobic stationary phase in liquid chromatography. A further progress in nanostructure based separation media or layer development has been reported in [4]. Nanopatterned surfaces (nanopillars) and nanoparticles have been already applied in electrophoretic and electrochromatographic separation [5].…”

Section: Introductionmentioning

confidence: 99%

Chemical Separation on Silver Nanorods Surface Monitored by TOF-SIMS

Petruš

Oriňák

Oriňáková

et al. 2017

Journal of Chemistry

View full text Add to dashboard Cite

The article introduces a possible chemical separation of a mixture of two compounds on the metal nanorods surface. A silver nanorods surface has been prepared by controlled electrochemical deposition in anodic alumina oxide (AAO) template. Rhodamine 6G and 4-aminothiophenol have been directly applied to the sampling point on a silver nanorods surface in an aliquot mixture. The position of the resolved compounds was analysed by time-of-flight secondary ion mass spectrometry (TOF-SIMS) which measured the fragments and the molecular ions of the two compounds separated on the silver nanorods surface. Rhodamine 6G has been preconcentrated as 1.5 mm radial from the sampling point while 4-aminothiophenol formed a continuous self-assembled monolayer on the silver nanorods surface with a maximum molecular ion intensity at a distance of 0.5 mm from the sampling point. The separation of the single chemical components from the two-component mixture over the examined silver nanostructured films could clearly be shown. A fast separation on the mentioned nanotextured films was observed (within 50 s). This procedure can be easily integrated into the micro/nanofluidic systems or chips and different detection systems can be applied.

show abstract