Weber G, Messerschmidt J, von Bohlen A, Alt F
Institut für Spektrochemie und Angewandte Spektroskopie, Dortmund, Germany.
Fresenius J Anal Chem. 2001 Dec;371(7):921-6. doi: 10.1007/s002160101056.
The species patterns of nutrient and trace metals (K, Ca, Mg, Mn, Fe, Zn) obtained by extraction of plant roots have been determined as a function of extraction pH in the range 4-9. The extractable metal concentrations were subdivided into low-molecular-weight (<10 kDa) and high-molecular-weight (>10 kDa) metal species by TXRF analysis. Except for pH 9, the low-molecular-weight fraction is predominant. This fraction was further separated by HPLC with AAS detection. It was demonstrated that the nature of the metal species changes dramatically when the extraction pH is changed, especially in the range 9-7. Information about the chemical nature of chromatographically separated metal species is obtained by use of different electrochemical detectors (amperometric detection at a glassy carbon or copper electrode and pulsed amperometric detection) and diode-array UV detection.
通过植物根系提取获得的养分和痕量金属（钾、钙、镁、锰、铁、锌）的物种模式已被确定为提取pH值在4-9范围内的函数。通过全反射X射线荧光光谱分析，可提取的金属浓度被细分为低分子量（<10 kDa）和高分子量（>10 kDa）金属物种。除了pH值为9时，低分子量部分占主导。该部分通过高效液相色谱与原子吸收光谱检测进一步分离。结果表明，当提取pH值改变时，尤其是在9-7范围内，金属物种的性质会发生显著变化。通过使用不同的电化学检测器（玻碳电极或铜电极上的安培检测和脉冲安培检测）和二极管阵列紫外检测，可获得色谱分离的金属物种化学性质的信息。
