Use of a flow-injection sample manipulator as an interface between a "high-performance" liquid chromatograph and an...

We describe an integrated, molecular-absorbance, atomic absorption instrument for studying metal/ligand binding in clinical samples. For an interface between the "high-performance" liquid chromatograph and the atomic absorption instrument we used a flow-injection sample manipulator, thus allowing both the chromatograph and the atomic absorption detector to operate at their separate optimum conditions. After specimen separation with a gel permeation column, we measured the molecular components of the column eluate by molecular absorbance spectrometry and the atomic components (calcium and magnesium) by flame atomic absorption spectrophotometry. This instrument system is capable of separating and analyzing multiple components within 20 min of injection of the sample on the column. The chromatograms presented demonstrate the utility of the system for investigating metal binding to a variety of ligands in clinical samples.