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GE Newsletter June 2017

Figure 10. Glass Expansion Twister baffled cyclonic spray chamber design features. Helix fixes nebulizer depth and provides the optimum interface for minimizing dead volume Precisely placed groove guarantees smooth draining Baffle cut at angle and fused to bottom prevents droplet formation Vertical wall ensures maximum transport efficiency UniFit connector and capillary included with all pumped drain chambers Application Spotlight Figure 8. Signal stability obtained from a homogeneity assessment of a custom blend CRM when using the fully ceramic D-Torch compared to a semi-demountable quartz torch. 0 50 100 150 200 250 Analysis Time (min) % Normalized Intensity 110% 105% 100% 95% 90% 85% Zn 334.502nm 3.0% TDS D-Torch/Ceramic/HF Intro System Zn 334.502nm 2.2% TDS Semi-Demountable Torch/HF Intro System NI 174.828nm 3.0% TDS D-Torch/Ceramic/HF Intro System NI 174.828nm 2.2% TDS Semi-Demountable Torch/HF Intro System Pb 220.353nm 3.0% TDS D-Torch/Ceramic/HF Intro System Pb 220.353nm 2.2% TDS Semi-Demountable Torch/HF Intro System New D-Torch models have recently been released for the Agilent 5100 and 5110 ICP-OES, PerkinElmer Avio ICP-OES, SPECTRO Arcos II and SPECTRO Blue ICP-OES (Figure 9). These new D-Torch models feature the same auto aligning and locking mechanism of the corresponding standard torches, but in a robust demountable design which is compatible with a ceramic outer tube. The D-Torch is currently available for a range of ICP-OES and ICP-MS instruments, see the Glass Expansion website for a complete list. Figure 9. New D-Torch releases. Agilent 5100/5110 PerkinElmer Avio SPECTRO Blue SPECTRO Arcos II/ Spray Chamber Selection Glass Expansion spray chambers are manufactured with specific design features to provide the utmost performance. The design characteristics of the TwisterTM cyclonic spray chamber are detailed in Figure 10. Unique to all Glass Expansion spray chamber designs is our proprietary HelixTM zero dead volume nebulizer interface. Eliminating the dead volume around the nebulizer seal leads to faster washout times and higher sample throughput. This improvement in washout is shown in Figure 11, where a 10 ppm standard washes out in 4 seconds with the Twister compared to 16 seconds with a “Brand-X” spray chamber.9 Washout is especially important with high matrix samples, as high concentrations will take longer to completely rinse out. Figure 11. 10 ppm Mo washout Comparison between Helix and non-Helix spray chambers. 1 2 4 6 8 10 12 14 16 18 Time (seconds) Emission Counts 0 8000 6000 4000 2000 The Twister cyclonic spray chamber also features a central transfer tube, which acts as a secondary droplet filter to reduce the mean droplet size. This helps to reduce the sample load within the plasma without compromising detection limits and improving precision (% RSD). The reduced sample load helps to increase torch life, slow salt build-up at the injector tip, and decrease the frequency of cleaning ICP-MS interface cones. These features make a baffled cyclonic spray chamber, like the Twister, the ideal choice for a high TDS application. Nebulizer Selection When dealing with high TDS samples, we recommend using the SeaSprayTM, Glass Expansion’s worldwide market-leading high performance concentric glass nebulizer. The SeaSpray comprises a unique self-washing tip designed to prevent crystal growth, providing a tolerance of up to 20% TDS. The SeaSpray’s popularity is due to its ability to offer outstanding nebulization efficiency for trace level analyses combined with excellent precision and a high tolerance to TDS. www.geicp.com Glass Expansion Newsletter | Issue 43 4


GE Newsletter June 2017
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