title: Immunochromatography for the rapid determination of cadmium concentrations in wheat grain and eggplant.
abstract: BACKGROUND
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba 305-8604, Japan. abekaoru@affrc.go.jp
authors.forename: Kaoru
authors.initials: K
authors.lastname: Abe
authors.forename: Katsuo
authors.initials: K
authors.lastname: Nakamura
authors.forename: Tomohito
authors.initials: T
authors.lastname: Arao
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Sakurai
authors.forename: Ayumi
authors.initials: A
authors.lastname: Nakano
authors.forename: Chieko
authors.initials: C
authors.lastname: Suginuma
authors.forename: Kei
authors.initials: K
authors.lastname: Tawarada
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Sasaki
mesh_terms: D002104:Cadmium / Q000032:analysis* / Q000302:isolation & purification; D002845:Chromatography / Q000379:methods*; D004492:Edetic Acid / Q000276:immunology; D002523:Edible Grain / Q000737:chemistry; D005504:Food Analysis / Q000379:methods*; D005638:Fruit / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000379:methods; D010936:Plant Extracts / Q000032:analysis* / Q000737:chemistry; D012016:Reference Values; D032323:Solanum melongena / Q000737:chemistry*; D014131:Trace Elements / Q000032:analysis* / Q000302:isolation & purification; D014908:Triticum / Q000737:chemistry*
chemical_list: D010936:Plant Extracts; D014131:Trace Elements; D002104:Cadmium; D004492:Edetic Acid