We describe the general aspects of ion chromatography and how on-line counted ion-exchange techniques can be utilized to determine pyruvic and lactic acids in plasma and vanillymandelic acid in urine. Pyruvate and lactate are extracted from deproteinized plasma by use of an ion-exclusion resin. After elution from the resin, the plasma extract is chromatographed on an anion-exchange column, with...

The case of a sorption process considered here involves a solid phase (sorbent) and a liquid phase (solvent, normally water) containing a dissolved species to be sorbed (sorbate, e.g. metal ions). Due to the higher ‘affinity’ of the sorbent for the sorbate species the latter is attracted into the solid and bound there by different mechanisms. This process takes place until an equilibrium is est...

For purification of peptides, it is often difficult to use methods similar to those applied in the purification of other organic compounds, mainly due to their complexity. Purification of organic molecules often uses methods based on crystallization to isolate the desired molecule. As efficiency and high yields are of vital importance for optimal economy of any industrial manufacturing process,...

2 3 Na two-dimensional nutation N M R was applied to N a t + *Zr 2 Si v P 3 _ v O, 2 with x = 0, 1, and 2. The nutat ion spectrum in each compound consists of two clearly separated peaks corresponding to the two crystallographically inequivalent sodium sites. In the compound with x = 2 the nuclear quadrupole coupling constants (e Qq/h) and the asymmetry parameters (rj) were by spectral simulati...

Ion exchange resins are used in several chemical decontamination or cleaning processes and in nuclear industries for removal of radionuclides.1–5 Nowadays, ion exchange resins are not only used for separation but also as catalysts. In the past decade, inorganic ion exchange materials have emerged as an increasingly important replacement or complement to conventional organic ion exchange resins....

結晶性配位高分子（CCP）および多孔質なCCPであるMOFにおける金属イオン交換は，新たな機能性物質の合成法として有効である。CCPおよびMOFの結晶構造の柔軟性がイオン交換反応特性に大きく影響するはずであるが，これまでそのような議論はほとんどされてこなかった。本研究では，Ce3＋とビス（4-ニトロフェニル）リン酸が形成するCCP（CeL3）を合成し，CeL3中のCe3＋と水溶液中に過剰に存在するランタノイドイオン（Ln3＋; Ln3＋≠Ce3＋）の交換反応を調べた。原子番号が隣合うTm3＋とYb3＋で配位高分子中の金属イオンモル分率がおおよそ0と1になるという，原子番号に対して不連続に変化する極めて珍しい選択性序列を見出した。溶液条件次第では，Er3＋とYb3＋およびYb3＋とLu3＋で不連続な変化となった。CeL3でのイオン交換反応が進行するには，イオン交換反応によって生じる混合...

Ž . Ž . An ion-selective field effect transistor ISFET was applied as a potentiometric detector in liquid chromatography LC for the Ž determination of organic acids. The ISFET was prepared by coating the gate insulator of the encapsulated transistor with a poly vinyl . Ž . chloride PVC matrix membrane containing methyltridodecylammoniumchloride, which enables the detection of organic anions. Th...