Fluorescence indicators, organic

Organic fluorescence indicators for aluminium oxide, silica gel and cellulose layers (code F366, UV366) include ... 

Implementation A dry-ashing procedure removed the organic portion of the cream (85%) and X-ray fluorescence indicated large amounts of tin. X-ray diffraction of the cream provided a scattering pattern that was determined to be tin (IV) oxide (Fig. 21.17). 

As a result of both intensive as well as extensive research a number of organic and inorganic substances have been identified that positively demonstrate an improved visualization . Such substances are termed collectively as fluorescent indicators . 

Figure 17. Fluorescence behavior of the organic phase can be an important indicator of the composition of the oil phase or of oil-solid interactions. These oil components (bitumen associated with clays versus bitumen that is clay-free) clearly differ in fluorescence behavior, a result indicating different organic-phase compositions or different oil-solid interactions. In this black-and-white reproduction, the oil component that fluoresces blue (B) appears brighter than the component that is fluorescing yellow (Y). The free organic component exhibits the blue fluorescence the organic material associated with clays fluoresces yellow.

These blocks were also examined for fluorescence using blue light excitation and the fluorescence colours of the organic material are shown in Table II. Both reflectance values and spore fluorescence indicate that the rank of most of the samples was within a window of about R 0,4 - 0.63%... 

Organic or inorganic binders are used to fix the silica layer on the surface of a glass plate. Furthermore, the layer generally contains an inorganic fluorescence indicator... 

The literature for peptide-membrane interactions is both vast and well covered. For the purposes of this chapter, we will look only at polymers - molecules made from polymerization reactions rather than solid-state synthesis or extracted from living organisms - made from a- and p-amino acids. Yaroslavov et al examined binding between poly-a-r-lysine (PLL) and anionic vesicles. SUVs of lecithin and cardiolipin were labeled with pyrene and exposed to PLL (Cl6) (Figure 21). The decrease in pyrene fluorescence indicated that PLL binds to the vesicles. Saturable binding was observed. The addition of high concentrations of salt or low... 

Biphenyl is usually determined by chromatographic analysis of an extract prepared using an organic solvent. In the TLC method, biphenyl is located under UV radiation, extracted with methanol, and determined spectrophotometrically at 248 nm. If the silica gel layer is impregnated with the fluorescent indicator GF254, biphenyl can be detected by densitometry. LC analysis with UV detection at 254 nm and fluorimetric detection at 350 nm with excitation at 285 nm are good alternatives. Derivative infrared spectrometry has also been developed as an alternative procedure. 

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