Determination of pheophytinatoiron(III) chlorides by reversed phase high performance liquid chromatography

Kenji FURUYA, Hidenari INOUE, Tsuneo SHIRAI
1987 Analytical Sciences  
A simple and accurate HPLC method was developed for the determination of pheophytinatoiron( III) chloride ( PheoFeCl ) prepared by the replacement of magnesium( I I ) in chlorophyll [pheophytinatomagnesium( II )] with iron( III). The good separation of PheoFeCl was obtained by using a stationary phase of C18 chemically bonded to silica gel and a mobile phase of acetone-acetonitrile (50:50, v/v). A tailing of the PheoFeCl peak due to the dissociation of ion pairs was improved by addition of
more » ... by addition of tetramethylammonium chloride to the mobile phase. The spectrophotometric method was also used for a comparison to the HPLC method. For the synthetic samples prepared by mixing (pheophytinato a )iron(I I I) chloride [(Pheo-a )FeCI] and (pheophytinato b )iron(I II) chloride [(Pheo-b)-FeCI)], analytical values by the spectrophotometric method were extremely high compared to those by the HPLC method because of interferences from the absorption of coexistent pigments. In the proposed HPLC method, ( Pheo-a )FeCI and ( Pheo-b)FeCI could be determined in the concentration range of 0.025-30 µg cm-3 and 0.06-30 µg cm 3 with relative standard deviations (n=10) of 6.2% and 18%, respectively.
doi:10.2116/analsci.3.353 fatcat:fohp6us4ivgbnp6rfp4dk723i4