Vapor Generation Accessory VGA–77 Operation manual

VGA–771. Introduction1.1 About the VGA–77The Vapor Generation Accessory 77 (VGA-77) is a vapor generationsystem for Atomic Absorption (AA), Inductively Coupled PlasmaOptical Emission Spectrometry (ICP-OES) and Inductively CoupledPlasma Mass Spectrometry (ICP-MS) applications.Vapor generation is an extremely sensitive procedure used fordetermining the level of mercury, arsenic, selenium and a range ofother hydride-forming elements. The sample capillary is placed in thesolution to be measured and the VGA-77 pumps the sample through areaction coil where it is automatically acidified and mixed with asuitable reductant. The resulting vapor is transferred to an atomizationcell for determination by the spectrometer.The VGA-77 is supplied in a modular form, with a pump unit andseparate reagent module. Since ICP and AA applications use differentgas/liquid separators, using separate plumbing assemblies for differentreagents enables:❏ Flexibility—the VGA-77 can be used with both AAs and ICPs❏ Quick and simple change of applications, for example from AAto ICP or between different types of analyses❏ Cleaner operation—there is no chance of cross-contaminationbetween applications❏ Ease of operation—there is no need to clean reagent bottles andtubing between applications as each application has a dedicatedreagent module. Similarly, you can change from AA to ICPapplications by changing reagent modules✒ Note Part numbers for additional reagent modules are listed insection 5.3.Publication date: May 2004 1-1