Dye cocktails

In Dr. M. Gratzel s plenary lecture at IPS-2000,103 he presented the following research topics to improve DSC. 1) Mastering the interfaces, electron transfer dynamics, control of dark current. 2) Charge transport in nanocrystalline films. 3) Panchromatic sensitizers, dye cocktail, quantum dot charge injection. 4) Light management, mixed metal oxide films, core-shell metal oxide films. 5) New... 

The polymer solution is spotted on a solid support or dispensed in the single wells of a microwell plate. After drying, the fluorescent dyes can be immobilized on these matrices. Direct spotting and drying of a mixed polymer/luminophore cocktail can be an alternative. 

Exceptions to this last observation are encountered when the colored materials happen to be present in the same phase where, because of their excessive absorbances, the signal-to-noise ratio is decreased. This kind of complication was successfully handled in direct analytical assays devised for lysergic acid diamide (LSD)f and phencyclidine (PCP) in illicit drugs spiked with intensely colored dyes for L-cocaine, morphine, and methadone in the pharmaceutical product commonly referred to as Brompton s cocktails and for D-pseudoephedrine in children s Sudafed. ... 

Two layers are formed on mixing. A few crystals of CUSO4 5 H2O are now added and the mixture stirred well. The flask is closed with a stopper and left to stand for several hours. The supernatant liquid is decanted off, the solution filtered and placed in the measuring cylinder. A few mL of xylene (previously been colored with Sudan III dye) are added. This deep red liquid forms the upper phase below it is the colorless methanol phase and at the bottom the aqueous phase which is colored blue by the copper sulfate. The measuring cylinder is closed with a cork stopper and sealed with paraffin. The mixture remains stable for several years. Prior to each demonstration the liquid is shaken thoroughly the cylinder is placed in front of a white background and the red, white and blue cocktail effect presented. 

If we are to examine any foodstuff using HPLC, we will need to remove the matrix prior to analysis. The Sudan red dyes will need to be extracted from the matrix. Food matter can be a complex mixture of animal and/or vegetable material containing a cocktail of many different compounds. Oil products contain complex mixtures of nonpolar hydrocarbon materials that are incompatible with most HPLC modes on their own. Thus, extraction of each matrix will be required before any analysis of the Sudan red dye is undertaken by HPLC. 

Im JS, Lee SK, Lee Y-S (2011) Cocktail effect of Fc203 and Ti02 semiconductors for a high performance dye-sensitized solar cell. Appl Surf Sci 257(6) 2164-2169... 

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