Male K B, Luong J H, Trani M
Biotechnology Research Institute, National Research Council Canada, Montreal, Quebec.
Appl Biochem Biotechnol. 1994 Jan;44(1):91-100. doi: 10.1007/BF02921854.
Water-soluble 2-hydroxypropyl-beta-cyclodextrin (Hp-beta-CyD), a cyclic and nonreducing oligosaccharide was used to enclose a hydrophobic guest molecule 1,1'-dimethylferrocene (DMF) to form a water-soluble yellow complex. At high concentrations (300 mM), Hp-beta-CyD enclosed up to 100 mM DMF. The yellow complex was electrochemically oxidized (platinum vs Ag/AgCl poised at +450 mV) to form a blue dye, 1,1'-dimethylferricinium (DMF+). This is a one-electron transfer process and the ferricinium cation formed exhibited an absorption peak at 650 nm. The concentrated DMF+ was stable for at least 4 mo at 4 degrees C and insensitive to a wide pH variation (pH 2-11). Application of the novel DMF+ complex as a colorimetric dye for the determination of uric acid in urine was successfully demonstrated. The reaction between the dye and uric acid is almost instantaneous and decrease in absorbance caused by the reduction of 1,1'-dimethylferricinium to 1,1'-dimethylferrocene can be followed at 650 nm. The results obtained agreed well with those of the reference reversed-phase HPLC method.
水溶性2-羟丙基-β-环糊精（Hp-β-CyD），一种环状非还原性寡糖，被用于包裹疏水性客体分子1,1'-二甲基二茂铁（DMF），以形成一种水溶性黄色络合物。在高浓度（300 mM）下，Hp-β-CyD可包裹高达100 mM的DMF。该黄色络合物经电化学氧化（铂对Ag/AgCl，电位为 +450 mV）形成蓝色染料1,1'-二甲基二茂铁阳离子（DMF+）。这是一个单电子转移过程，形成的二茂铁阳离子在650 nm处有一个吸收峰。浓缩的DMF+在4℃下至少稳定4个月，且对较宽的pH变化范围（pH 2 - 11）不敏感。成功证明了新型DMF+络合物作为比色染料用于测定尿液中尿酸的应用。染料与尿酸之间的反应几乎是瞬间发生的，由1,1'-二甲基二茂铁阳离子还原为1,1'-二甲基二茂铁所导致的吸光度降低可在650 nm处进行监测。所得结果与参考反相高效液相色谱法的结果吻合良好。
