COMPACT, FIELD-PORTABLE CAPILLARY ION CHROMATOGRAPH

We describe a fully computer controlled, field-portable capillary scal e suppressed conductometric ion chromatograph that fits in a standard briefcase (28x43x15 cm) and weighs 10 kg. The system uses an electrodi alytic sodium hydroxide generator on the high-pressure side of a syrin ge pump. This provides isocratic or gradient operation with excellent eluent purity. A 100 nl loop-volume, electrically actuated valve is us ed for sample injection and allows for facile automation. Analytical c olumns, 50 cmx180 mu m I.D., were packed in the laboratory using comme rcial packing and fused-silica capillaries. A novel flow-through condu ctivity detection cell was developed. The system provides detection li mits in the sub- to low ppb range, with mass limits of detection >100 times better than standard IC systems. Sample preconcentration is demo nstrated with a concentrator column, 10 cm in length. (C) 1998 Elsevie r Science B.V.