The Varian AA range includes the stylishand easy-to-use AA280 and AA240 series. Combining Fast Sequential design with up to eight lamp capability, the AA240/280 flame instruments provide high performance and lower running costs. If you require superior furnace performance and accurate
background correction, the AA280 Zeeman instrument delivers, with fast transverse Zeeman background correction and our new GTA120 graphite furnace. For an economical analysis solution, choose the AA240 series, which provides four lamp capacity and a choice of automation options.
Varian (Agilent) VGA 77 Vapor Generation Accessory
The Vapor Generation Accessory 77 (VGA 77) is a vapor generation system for Atomic Absorption (AA) and the VGA 77P is for Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) applications. Unless otherwise specified, both the VGA 77 and VGA 77P will be refered to as VGA 77 throughout the rest of this User’s Guide.
Vapor generation is an extremely sensitive procedure used for determining the level of mercury, arsenic, selenium and a range of other hydride-forming elements in samples. The sample capillary is placed in the solution to be measured and the VGA 77 pumps the sample through a reaction coil where it is automatically acidified and mixed with a suitable reductant. The resulting vapor is transferred to an atomization cell with AAS or to the plasma for ICP-OES for determination by the spectrometer.
The VGA 77 is supplied in a modular form, with a pump unit and separate reagent module. Since ICP and AA applications use different gas/liquid separators, using separate plumbing assemblies for different reagents enables:
- Flexibility—the VGA 77 can be used with both AAs and ICPs
- Quick and simple change of applications, for example from AA to ICP
- Cleaner operation—there is no chance of cross-contamination between applications
- Ease of operation—there is no need to clean reagent bottles and tubing between applications as each application has a dedicated reagent module. Similarly, you can change from AA to ICP applications by changing reagent modules