VG Elemental
 Ion Path, Road Three,
 Winsford, Cheshire,
 CW7 3BX England

Tel: +44 (0)1606 861022
Fax: +44 (0)1606 552588


Introduction

The VG PlasmaQuad 3 has been designed to provide not only improved analytical capabilities and flexibility, but also to be simpler to use through a new level of automation. The VG PlasmaQuad 3 features full automation of optimization routines and sample analysis in all modes of operation. In addition all ICP parameters, torch position and lens settings are under complete computer control. To enhance analytical flexibility, the VG PlasmaQuad 3 interfaces seamlessly with all of our advanced sampling accessories.

Automatic diagnostics continually monitor system functionality and real time usage and will alert the operator when routine or corrective maintenance is required. The system is designed to allow our specialist engineers to diagnose problems or run the instrument remotely from our service centres using our modem based TechConnectTM system.

Key features such as the PlasmaScreen Torch, the S-Option and AutoRange Plus provide significant improvements in data quality, accuracy and detection limits. Whilst VERTEX the new user-focused support program provides the VG PlasmaQuad 3 user with access to in-depth on-line training programs, remote system diagnostics and extended warranty coverage.

System Overview

Sample introduction into the ICP-MS is via a nebulizer/spray-chamber system, supplied by a computer controlled variable speed peristaltic pump. The sample introduction system (nebulizer, spraychamber and torch) is cassette based and the plasma torch is of a one-piece construction, ensuring accurate and consistent alignment. The sample aerosol is carried to the plasma by a nebulizer gas flow supplied through a mass flow controller. The sample droplets are dried, dissociated, atomised and ionised, before passing through the patented sample and skimmer cones, into the mass-spectrometer.

Extensive research into the design of the interface region of the VG PlasmaQuad 3 has resulted in the unique high performance interface, which has been optimized for maximum transmission and uniform response across the mass range, enabling simple optimization and analysis.

The mass spectrometer triple-stage vacuum system consists of a rotary pump for the expansion stage and two turbo-molecular pumps for the intermediate and analyser stages. This ensures excellent peak resolution, abundance sensitivity and uniformly low backgrounds, whilst maintaining the high ion transmission necessary for best detection limits.

The ion lens system, situated in the intermediate vacuum stage, is fully computer controlled and can be optimized manually or automatically using the inbuilt intelligent autotuning routines. The optic design ensures optimum ion transmission across the mass range, together with exceptionally low background count rates.

Ions are focused through the entrance of the high performance quadrupole mass spectrometer, where they are separated on the basis of their mass to charge ratio and takes full advantage of the good operating vacuum, to give excellent abundance sensitivity and peak shapes.

The detector used in the VG PlasmaQuad 3 is an electron multiplier, an ion striking the first dynode releases electrons which accelerate into a dynode beneath which in turn releases more electrons. The electron cloud cascades down the body of the detector increasing at every dynode. The resulting electron cloud can be counted as a single pulse at the base of the detector. The pulse counting mode is augmented by an analogue signal. The electron current is measured approximately half way along the length of the detector, and is digitised into pulses by the counting electronics. The detector system provides a linear dynamic range of 8 orders of magnitude.

Key Features

PlasmaScreen

A fully automated dual mode ion source, which is designed to operate in the standard (high energy) mode for the majority of elemental determinations and in a cool plasma mode for the determination of selected elements.

The cool plasma virtually eliminates the interferences and background noise which have, until now, impeded the determination of the "problem" elements such as Na, K, Fe, Ca, etc. The automated design of the PlasmaScreen Torch combined with the auto-tuning capability of the VG PlasmaQuad 3 allows the system to switch between the two modes of operation without operator intervention. Samples can be automatically analyzed under both sets of plasma conditions ensuring the best possible data quality.

S - Option

An ultra-high efficiency ion sampling interface designed for both solution and solids-based applications where routine measurements at ultra-trace levels are needed. This unique interface improves sensitivity by approximately an order of magnitude above the standard instrument performance, while the background intensity remains unchanged. This allows routine elemental determination at ppq levels.

Furthermore, the S-Option can be used in conjunction with the PlasmaScreen Torch giving the ultimate in cool plasma performance. The full automation of the VG PlasmaQuad 3 allows the system to switch from S-Option to standard interface mode without operator intervention. Cool plasma conditions may be selected with either interface mode. These capabilities make the VG PlasmaQuad 3 the most versatile ICP-MS system available.

AutoRange Plus

This advanced detector system provides a linear dynamic range of 8 orders of magnitude through simultaneous monitoring of both the analog and pulse counting outputs of its discrete dynode electron multiplier. This sophisticated detection system ensures that all elements over a wide concentration range (108) will be determined accurately, whether from steady-state or transient signals generated by sampling accessories. These include the PrepLab and UV MicroProbe laser ablation system. AutoRange plus also increases productivity for routine sample analyses, e.g. environmental analyses, which involve the determination of elements at both high and low levels in the same samples.

VERTEX

The VERTEX program provides all VG PlasmaQuad 3 users with access to in-depth training programs, remote system diagnostics and extended warranty coverage for their instrument. VERTEX includes a 12 month labor and a 24 month parts warranty with priority response for all support requirements. It also incorporates our remote diagnostics package TechConnectTM. Should you require assistance, our product specialists can log onto your system, via modem, and access the on-board diagnostics to help identify the cause of your concern. System checks and all instrument tuning can be performed remotely. With TechConnectTM diagnosis prior to a service visit our service specialists will be better prepared to effect repairs quickly and efficiently once on-site. Remote diagnostics helps to ensure maximum up-time and facilitates applications support. In recognition of the truth of the old adage "Prevention is better than cure" the program also includes a preventative maintenance visit after 6 months to ensure maximum instrument reliability.

VERTEX is designed to be more than a service package. Before an order is placed, your local service group will contact you to ensure that you are familiar with the benefits of the program. VERTEX provides guaranteed levels of support for you wherever you might be and instant access to our full range of support services around the world. Priority response in the important areas of spare parts, technical advice and field service are key to the successful operation of any laboratory. VERTEX membership guarantees these are available.

Membership can be extended beyond the standard warranty period through our comprehensive range of service and maintenance contracts.



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