BUFFER FOR ANALYZING SMALL INORGANIC CATIONS BY CAPILLARY ELECTROPHORESIS

摘要

Disclosed herein is electrophoresis buffer and a buffer kit useful in the analysis of small cations in samples containing simple orcomplex mixture of ions and/or neutral organic compounds in a short time and to scan unknown samples for the small cations by capillaryelectrophoresis with indirect optical detection. An embodiment of the disclosed CE buffer comprises complexing agents and chromophoreco-ions. One of the complexing agents is a multidentate one of donor atoms of oxygen and nitrogen, particularly nitrilotriacetic acid (NTA).Other complexing agents, if any, can be crown ethers, for example, 18-crown-6. The chromophore co-ions can be produced by introducingnitrogen-containing heterocyclic compounds, in particular pyridine, to the electrophoresis buffer. The desired pH of the buffer kit isbetween about 2 and 4. In a particularly preferred embodiment, the buffer kit comprises a UV chromophore co-ion of nitrogen-containingheterocyclic compound of pyridine in a range of about 1 mM to about 40 mM, a multidentate complexing agent of donor atoms of oxygenand nitrogen of nitrilotriacetic acid (NTA) in a range of about 0.1 mM to about 5mM and a crown ether of 18-crown-6 in a range of about0.1 mM to about 50 mM. The desired pH is about 3. Indirect UV detection is made at 254 nm.