Reagent system and its use in spectrometric determination of low and high molecular weight PEGs in an aqueous fluid, method for determining the intestinal permeability with said system

摘要

The present invention is concerned with (a) a reagent system and its use in spectrometric determination of polyethylene glycol (PEG) in an aqueous fluid to be tested, such as a biological fluid, said reagent system comprising two different colour-forming reagents: a first reagent for determining low molecular weight (lmw) PEG, which contains phosphomolybdic acid, a strong acid (such as HCl or trifluoroacetic acid) and barium chloride, said first reagent giving a yellowish to greenish cloudiness in the presence of lmw PEG, and a second reagent for determining high molecular weight (hmw) PEG, which contains a cobalt II salt and thiocyanate, said second reagent giving a blue to violet cloudiness in the presence of hmw PEG; (b) a method for determining intestinal permeability with said reagent system; and (c) a dosage kit for carrying out said method.