Polyethylene glycol , fluorescent

Similar fluorescence-stabilization has been reported for polyethylene glycol 4000 by Wintersteiger [291]. 

Polyethylene glycol 4000 silymann enhancement 5% in ethanol, optimum for fluorescence after 24 h [274]... 

Note A 5% solution of polyethylene glycol 4000 in ethanol can be sprayed onto the chromatogram [2, 4] for the purpose of increasing and stabilizing the fluorescence instead of dipping it in liquid paraffin - -hexane (1 - - 2). If this alternative is chosen the plate should not be analyzed for a further 30 min since it is only then that the full intensity of the fluorescence develops [6]. 

Substance zones are produced that mainly yield blue fluorescence under long-wavelength UV light (A = 365nm) (indoles occasionally fluoresce yellow [15]), colored zones are also produced occasionally. The fluorescence is stabilized by immersing in 20% methanohc polyethylene glycol solution [5]. 

The following Tables 2.1 to 2.3 summarize some examples based exclusively on thermochemical reactions on the sorbent surface which lead to the formation of fluorescent reaction products. The derivatives formed frequently remain stable for weeks [6] and the fluorescence can frequently be intensified and/or be stabilized by treatment with viscous liquids (liquid paraffin, Triton X-100, polyethylene glycol etc.). 

Kamimura M, Miyamoto D, Saito Y, Soga K, Nagasaki Y (2008) Design of polyethylene glycol)/streptavidin co-immobilized upconversion nanophosphors and their application to fluorescence biolabeling. Langmuir 24 8864-8870... 

Ba azide has not been used as an expl, bur it has been used in the manuf of fluorescent lamps and radio tubes (Ref 12a 19)- It has also found use as a blowing agent during the vulcanization of cellular rubber (Ref 22). The expl reaction of Ba azide is prevented by adding gelatin, machine oil or Neugen (polyethylene glycol laurate)... 

Confocal laser scanning microscopy can be used in conjunction with microwave heating for examining the three-dimensional structure and cellular interrelationships in sections of paraffin-embedded tissues (Boon and Kok, 1994). Tissues are fixed with Kryofix, a coagulant fixative containing 50% ethyl alcohol and polyethylene glycol (PEG molecular weight 300) for 90 sec in a microwave oven. The use of thick paraffin sections (15 (xm) and fluorescently labeled antibodies is preferred. 

O Neal DP, Meledeo MA, Davis JR, Ibey BL, Gant VA, Pishko MV, Cote GL (2004), Oxygen sensor based on the fluorescence quenching of a ruthenium complex immobilized in a biocompatible polyethylene glycol) hydrogel, IEEE Sensors Journal 4 728 - 734. 

Another successful example is the separation of a series of steroids listed in Fig. 6.11 using a monolithic capillary column prepared by redox initiated polymerization of a solution of acrylamide 4, methylene bisacrylamide 5, vinylsulfonic acid 12, and dodecyl acrylate 18 in N-methylformamide/TRIS-boric acid buffer (pH 8.2) to which polyethylene glycol) (MW 10,000) was added (overall composition 5% T, 60% C, 10% vinylsulfonic acid, 15% lauryl acrylate, 3% polyethylene glycol)). The capillary tube was first vinylized and its part beyond the detection window was coated with linear polyacrylamide to avoid band broadening. Since laser induced fluorescence was used to decrease the detection limit of the method to about 100 attomoles for neutral steroids, all of the analytes were first tagged with dansylhydrazine. Fig. 6.12 shows an... 

Separations of complex steroid mixtures were achieved recently by Que et al. [76] using both isocratic and gradient elution. Mass spectrometric detection gave femto-mole detection limits while laser-induced fluorescence of dansylated ketosteroids ranged in attomole levels (Fig. 10.16). Monolithic column packings were used with a 35 cm (25 cm packed bed) x 100 pm i.d. capillary packed with a polymer prepared from 5% T (total monomer concentration), 60% C (total crosslinker concentration), 3% polyethylene glycol, 10% vinylsulfonic acid and 15% lauryl acrylate. Details of the monolithic column preparation can be found in refs. 36,76, and 193. Similar monolithic columns can be used for the separation of bile acids [194],... 

Nakayama-Ratchford N, Bangsaruntip S, Sun X et al (2007) Noncovalent functionalization of carbon nanotubes by fluorescein-polyethylene glycol supramolecular conjugates with pH-dependent absorbance fluorescence. J Am Chem Soc 129 2448-2449... 

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