Solid phase extraction, hydrogen peroxide determination

Solid phase extraction, hydrogen peroxide determination, 635... 

Solid-phase extraction is routinely used to clean up extracts prior to quantitation (19,42,70, 80-82). Alternatively, endogenous fluorescent artifacts in food samples can be eliminated by oxidation with potassium permanganate/hydrogen peroxide/sodium metabisulphite. Benzyl alcohol has been used to extract riboflavin selectively without the coenzymes, permitting the determination of free riboflavin. 

LC combined with postcolumn chemiluminescence detection has also been applied to the determination of trace N-nitrosamines in groundwater The method combines solid-phase extraction (SPE) on to a mini-activated carbon column, followed by elution with acetone and concentration of the extracts by denitro-sation and fluorogenic derivatization. Peroxyoxalate chemiluminescence detection was carried out by using bis(2-nitrophenyl) oxalate and hydrogen peroxide as chemilumigenic reagents. The method provides N-nitrosamines detection at picomole per liter levels. 

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