Tiljander A, Skarping G
Department of Occupational and Environmental Medicine, University Hospital, Lund, Sweden.
J Chromatogr. 1990 Jul 6;511:185-94. doi: 10.1016/s0021-9673(01)93284-4.
A liquid chromatographic method using multi-wavelength UV detection (258 and 285 nm) is presented for the determination of 4,4'-methylenedianiline (MDA) in hydrolysed human urine. The method is based on hydrolysis under strongly acidic conditions followed by derivatization with pentafluoropropionic anhydride. The perfluoro fatty acid amide derivative formed was analysed on a bonded octadecylsilyl column using isocratic elution with acetonitrile-water (67:33, v/v) as mobile phase. The overall recovery for urine samples containing 115 micrograms/l of MDA was 97 +/- 3%. The calibration graph was linear in the investigated range (12-122 micrograms/l) with a correlation coefficient of 0.998. The precision was 2.3% for urine samples containing 122 micrograms/l and the detection limit was 8 micrograms/l. The chromatograms were evaluated using a combination of retention time data and absorbance ratio by the simultaneous monitoring of the wavelengths 285 and 258 nm. The absorbance ratio (285/258 nm) was virtually constant (0.28 +/- 0.04) in the range 78-10,000 micrograms/l. The precision for the absorbance ratio was 6.1% for urine samples containing 124 micrograms/l and the lowest amount of MDA to give an absorbance ratio was 50 micrograms/l. The procedure for the hydrolysis of urine spiked with MDA and N,N'-diacetyl-MDA and urine from skin-exposed workers was studied under strongly acidic, weakly acidic and basic conditions. MDA was found in hydrolysed urines from skin-exposed epoxy resin workers in the concentration range 8-700 micrograms/l.
本文介绍了一种采用多波长紫外检测（258和285 nm）的液相色谱法，用于测定水解人尿中的4,4'-亚甲基二苯胺（MDA）。该方法基于在强酸性条件下水解，然后用五氟丙酸酐进行衍生化。形成的全氟脂肪酸酰胺衍生物在键合十八烷基硅烷柱上进行分析，以乙腈 - 水（67:33，v/v）作为流动相进行等度洗脱。含115微克/升MDA的尿样的总回收率为97±3%。在所研究的范围（12 - 122微克/升）内校准曲线呈线性，相关系数为0.998。含122微克/升的尿样的精密度为2.3%，检测限为8微克/升。通过同时监测285和258 nm波长，结合保留时间数据和吸光度比来评估色谱图。在78 - 10,000微克/升范围内，吸光度比（285/258 nm）实际上是恒定的（0.28±0.04）。含124微克/升的尿样的吸光度比精密度为6.1%，产生吸光度比的最低MDA量为50微克/升。研究了在强酸性、弱酸性和碱性条件下，加标了MDA和N,N'-二乙酰 - MDA的尿样以及皮肤暴露工人的尿样的水解过程。在皮肤暴露的环氧树脂工人的水解尿样中发现了浓度范围为8 - 700微克/升的MDA。
