SIMPLE, INEXPENSIVE SYSTEM FOR CONTROLLED-DISPERSION FLOW-ANALYSIS ININDUCTIVELY-COUPLED PLASMA SPECTROMETRY

An inexpensive peristaltic pump has been modified for computer control and coupled to a commercial autosampler to provide completely automat ed sample introduction and calibration via controlled-dispersion flow injection. Precision of 4.2% RSD can be achieved with an injection vol ume of 10 uL or larger. With this device, controlled-dispersion flow a nalysis was used for computer-controlled standard calibration of Ca+2 from a single concentrated sample; a dilution of 180-fold of a 10-mug/ mL Ca+2 sample was readily achieved. Intelligent control of the system was also realized through the implementation of a LabVIEW software sy stem on a Macintosh computer. Advantages of the new system are the ben efit of simplicity and low cost for flow-injection analysis, a reducti on in sample consumption, and the convenience of performing single-sta ndard calibration.