Parameters and practical experience

On the basis of our long experience with two sequential (JY 38 and JY 38 Plus, Instruments S.A.) and one simultaneous ICP-spectrometer (JY 48, Instruments S.A.) as 

The spectral dispersion of various gratings is shown in Figs. 3-6 for the example of Zn in presence of Mg (A, = 202, 548 nm). 

This is only one example of the necessity for a sufficient optical resolution. It would be also very important for accurate background correction as will be described later or for avoiding systematic errors in practical analysis caused by possibie line interferences. 

Generally, one can obtain similar limits of detection with both the excitation units. In some cases, e.g. for the determination of Al, Li, Si, Pb and Tl, the DCP is more sensitive. The detection limits for Al and Li are about ten times lower in case of DCP compared with ICP. This fact is very useful for the determination of Li in the physiological range in body fluids like blood-serum and urine (Fig. 7) or e.g. for the determination of Al in serum or urine (Fig. 8) or dialysis patients. It is well known that the physiological range of Al in blood-serum is below 5 g/L and probably below 1 g/L, so it can not be detected by this method. But in the case of dialysis patients the concentrations in serum increase in some cases (encephalopathy) up to some hundred fiqlL, a range which is easily detectable. 

COMPARiSON OF RESULTS ON iDENTICAL SAMPLE SOLUTIONS (1645 = NBS river sediment 1632 A = NBS coai SL2 = BCR sewage sludge S06 = BCR soil). 

---