Tucker Samuel P
National Institute for Occupational Safety and Health, Cincinnati, OH 45226, USA.
J Environ Monit. 2008 Nov;10(11):1337-49. doi: 10.1039/b809790a. Epub 2008 Sep 29.
Three sampling and analytical methods have been developed and evaluated for ortho-phthalaldehyde (OPA): (1) an HPLC-UV method for OPA in air, (2) a fluorimetric method for OPA on surfaces, and (3) a colorimetric method for OPA on surfaces. (1) The air sampler contains 350 mg of silica gel coated with 1 mg of acidified 2,4-dinitrophenylhydrazine (DNPH). Air sampling may be conducted at 0.03 to 1.0 L min(-1) for periods up to 8 h. Samples were eluted with ethyl acetate, and the eluents were allowed to stand for 72 h. Analysis was by high performance liquid chromatography (HPLC) with a UV detector set at 369 nm. An unusual phenomenon was the observation that the stability of the sample on a sampler at 3 degrees C tends to decrease as the total quantity of OPA collected on the sampler decreases. Elution of the samples within 24 h of air sampling is required. The detection limit (LOD) is approximately 0.02 microg of OPA per sample. OPA on surfaces may be collected with strips cut from a sheet of polyvinyl alcohol (PVA wipe). (2) In the surface wipe method with analysis by fluorescence measurement, the strips of PVA wipe were placed into dimethyl sulfoxide. An aliquot was treated with aqueous N-acetyl-l-cysteine and ethylenediamine. Analysis was performed with a portable fluorometer (excitation and emission wavelengths = 365 nm and 438 nm, respectively). The LOD is 0.2 microg per sample. (3) In the surface wipe method with visual colorimetric detection, the strips of PVA wipe were placed into 30 : 70 acetonitrile : water. An aliquot was treated with N-(1-naphthyl)ethylenediamine in 0.1 m sulfuric acid. After color development, the LOD is approximately 48 microg per sample. These methods have been field tested in a hospital.
已开发并评估了三种用于邻苯二甲醛（OPA）的采样和分析方法：（1）用于空气中OPA的高效液相色谱 - 紫外（HPLC - UV）法，（2）用于表面OPA的荧光法，以及（3）用于表面OPA的比色法。（1）空气采样器包含涂有1 mg酸化2,4 - 二硝基苯肼（DNPH）的350 mg硅胶。空气采样可在0.03至1.0 L min⁻¹的流速下进行，最长8小时。样品用乙酸乙酯洗脱，洗脱液静置72小时。通过配备设置在369 nm的紫外检测器的高效液相色谱（HPLC）进行分析。一个不寻常的现象是观察到，当采样器上收集的OPA总量减少时，3℃下采样器上样品的稳定性趋于下降。需要在空气采样后24小时内洗脱样品。检测限（LOD）约为每个样品0.02 μg OPA。表面上的OPA可用从聚乙烯醇片材上剪下的条带（PVA擦拭布）收集。（2）在通过荧光测量进行分析的表面擦拭法中，将PVA擦拭布条放入二甲基亚砜中。取一份等分试样用N - 乙酰 - l - 半胱氨酸水溶液和乙二胺处理。使用便携式荧光计（激发和发射波长分别为365 nm和438 nm）进行分析。检测限为每个样品0.2 μg。（3）在具有目视比色检测的表面擦拭法中，将PVA擦拭布条放入30:70的乙腈:水中。取一份等分试样用0.1 m硫酸中的N - （1 - 萘基）乙二胺处理。显色后，检测限约为每个样品48 μg。这些方法已在一家医院进行了现场测试。
