National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba 305-8604, Japan.
J Sci Food Agric. 2011 Jun;91(8):1392-7. doi: 10.1002/jsfa.4321. Epub 2011 Feb 18.
A simple and quick on-site test for trace levels of cadmium (Cd) in food is needed because of the human toxicity of this heavy metal. We developed an immunochromatography kit which uses the antigen-antibody complex reaction between the Cd-ethylenediaminetetraacetic acid (Cd-EDTA) complex and an anti-Cd-EDTA antibody. We previously reported the successful use of this kit to determine Cd concentrations in brown rice with respect to the international standard: 0.4 mg kg⁻¹. Here, we measured, using this immunochromatography kit, Cd concentrations in crops with lower international standards than rice.
Cadmium extracted with 0.1 mol L⁻¹ HCl from wheat grain and fresh eggplant was purified sufficiently using an ion-exchange column treatment. Appropriate HCl extraction rates and dilution rates for the column eluate were selected; Cd concentrations in wheat grain and fresh eggplant were determined successfully by immunochromatography with respect to the international standards of 0.2 mg kg⁻¹ and 0.05 mg kg⁻¹ fresh weight, respectively.
Approximate Cd concentrations in wheat grain and fresh eggplant can be monitored easily and quickly by this method at locations where facilities for acid digestion and precision analysis are not available.
由于重金属镉的毒性，需要一种简单、快速的现场检测痕量食品中镉的方法。我们开发了一种免疫层析试剂盒，该试剂盒利用镉-乙二胺四乙酸（Cd-EDTA）络合物与抗 Cd-EDTA 抗体之间的抗原-抗体复合反应。我们之前曾报道过该试剂盒成功用于根据国际标准（0.4mgkg-1）测定糙米中的镉浓度。在这里，我们使用该免疫层析试剂盒测量了国际标准低于大米的作物中的镉浓度。
用 0.1molL-1 HCl 从麦粒和新鲜茄子中提取的镉，经离子交换柱处理后得到充分的纯化。选择了合适的 HCl 提取率和柱洗脱液的稀释率；根据国际标准 0.2mgkg-1和 0.05mgkg-1鲜重，成功地通过免疫层析法测定了麦粒和新鲜茄子中的镉浓度。
在没有酸消解和精密分析设备的地方，该方法可方便、快速地监测麦粒和新鲜茄子中的近似镉浓度。
