アブストラクト(16巻1号:神奈川歯学)

神奈川歯学

Japanese

Title : 乳歯の微量金属の測定法に関する研究 塩酸-アセトン混合溶離液による微量金属Cd, Zn, Pb, Cuの陽イオン交換クロマトグラフィーとFlameless原子吸光法による定量性について
Subtitle : 原著
Authors : 進土久明
Authors(kana) :
Organization : 神奈川歯科大学小児歯科学教室
Journal : 神奈川歯学
Volume : 16
Number : 1
Page : 1-14
Year/Month : 1981 / 6
Article : 原著
Publisher : 神奈川歯科大学学会
Abstract : 「抄録」 乳歯歯質中の微量金属を正確に分析, 定量することは, 小児歯科学を追究するうえで大きな役割を果たすものと考えられる. さきに, 教室の西村らは歯質中のCd・Zn・PbおよびCuについて, Flameless原子吸光法による測定法の検討を加えてきた. その結果, Flameless原子吸光分光光度計を用いて歯質中の微量金属を定量する場合, 大過剰に存在するCaおよびPの除去とともに, 各微量金属を単離し, 一定濃度の酸溶媒を使用することが, 定量的分析のためには必要不可欠であるという結論を得た. しかし, この場合, 酒石酸緩衝液による金属のColumn Chromatographyを併用しているために, Flameless原子吸光分光光度計による測定の前に, 溶出緩衝液そのものの灰化操作を必要とした. そのため, さらに微量を精度よく定量するには, より有効な方法を開発することが望まれていた. そこで著者は, 極微量を正確に定量分析するには, 前処理操作が一つでも省略されることが, 定量精度の向上と簡易化につながる極めて重要な事柄と考え下記の検討を行った. すなわち, Macroporous Strongly Acidic Cation-Exchange Resin MP-50(200-400mesh)を充填材として, 揮発性緩衝液である塩酸-アセトン混合溶液のGradient(0.64M HCl, 40%-86% Acetone)により, 各微量金属を溶出させ, それらの分離能およびFlameless原子吸光法による定量精度について検索した. その結果, 以下の結論を得た. 1. 0.64M塩酸とアセトンの混合溶液を溶離液とした場合, 陽イオン交換樹脂MP-50は有効な金属の分離を示した. 2. 分取後, 灰化操作を必要としなかった. 3. 0.64M塩酸とアセトンの混合溶液は0.5M硝酸を溶媒としたときと, ほぼ同様の感度が得られた. 4. 各金属におけるWorking RangeはCd 25ppb, Zn 12.5ppb, Pb 50ppb, Cu 50ppb以下が適当であった. 5. 検出限界は濃度6.25ppbのレベルでCd 4.8×10-12g, Zn 4.8×10-12g Pb 5.8×10-12gおよびCu 1.0×10-11gの値が得られた. 6. 200ppb溶液の回収率については, Cd 100±1.5%, Zn 102±1.7%, Pb 102±3.5%, およびCu 103±0.6%の値が得られた. 7. 10ppbの金属を5回測定したときの変動係数はCd 0.74%, Zn 1.03%, Cb 2.45%, Cu 2.94%であった. 以上の結果より, Flameless原子吸光法による歯質中微量金属の定量に, 塩酸とアセトンの混合溶媒を溶離液とする陽イオン交換クロマトグラフィーによる金属の分離が, 極めて有効な方法であることが判明した.
Practice : 歯科学
Keywords :

English

Title : A Preliminary Study for Determination of Quantitative Analysis of Trace Elements in Primary Teeth Chromatographic separation of Cd, Zn, Pb and Cu on the cation-exchange resin, with a mixed solution of hydrochloric acid and acetone, and quantitative analysis of trace elements by the flameless atomic absorption spectrophotometer
Subtitle :
Authors : Hisaaki SHINJI
Authors(kana) :
Organization : Department of Pedodontics, Kanagawa Dental College
Journal : Kanagawa Shigaku
Volume : 16
Number : 1
Page : 1-14
Year/Month : 1981 / 6
Article : Original article
Publisher : Kanagawa Odontological Society
Abstract : Accurate analysis and quantitative determination of trace elements in primary teeth is considered to play a large part in analyzing various problem of concern to the Pedodontist. Previously, Nishimura et al. of the Department of Pedodontics, Kanagawa Dental College, examined a method of measuring Cd, Zn, Pb and Cu in the presence of excessive amounts of Ca and P by the flameless atomic absorption spectrophotometry. As a result of this examination, it was concluded that for the accurate quantitative analysis of such trace elements, the elimination of Ca and P existing excessively, was required. Such was accomplished by the metal column chromatography using a tartrated buffer solution which was necessitated to eliminate prior to measurement by the flameless atomic absorption spectrophotometer. The author, therefore, made the following examination. As a filler, a macroporous strongly acidic cation-exchange resin MP-50 (200-400 mesh) was used. Respective trace elements were separated by gradient of a mixed volatile solution of hydrochloric acid and acetone (0.64M HCl, 40-86% Acetone). Separation ability of respective trace elements and accuracy of the quantitative determination were examined. As the result of this examination, the following conclusions were drawn : 1. When a mixed solution of 0.64M hydrochloric acid and acetone was used as a separatery agent, the cation-exchange resin MP-50 exhibited complete separation of the elements used for this gradient system. 2. After separation of trace elements, no ashing was required for accurate analysis. 3. The mixed solution of 0.64M hydrochloric acid and acetone showed better trend of sensitivity, than a mixed solvent of 0.5M nitric acid and 0.64M hydorochloric acid. 4. Adequate working ranges of respective trace elements were 25 ppb, 12.5 ppb, 50 ppb and 50 ppb or less for Cd, Zn, Pb and Cu, respectively. 5. Minimal detectable amounts of those trace elements with the concentration of 6.25 ppb were calculated as 4.8×10-12g, 4.8×10-12g, 5.8×10-12g and 1.0×10-11g for Cd, Zn, Pb and Cu, respectively. 6. Recovery rates of trace elements were determined using 0.5ml of 200 ppb mixed solution for each trace element and obtained the values of 100+-1.5%, 102+-1.7%, 102+-3.5% and 103+-0.6% for Cd, Zn, Pb and Cu, respectively. 7. Coefficients for variations of trace elements of 10 ppb when these elements were measured 5 times were 0.7%, 1.0%, 2.4% and 2.9% for Cd, Zn, Pb and Cu, respectively. From the above results, it was shown that use of a gradient system with a mixed solution of hydrochloric acid and acetone, is an extremely effective means for the quantitative determination of trace elements in primary teeth by the flameless atomic absorption spectrophotometry method.
Practice : Dentistry
Keywords :