Application Spotlight
In 2016 the Direct Connect (DC) nebulizer product line was released,
combining the benefits of our proprietary UniFitTM zero dead volume
sample connector and full-length VitriCone capillary10 with an
improved gas connection assembly. The features of the SeaSpray
DC nebulizer are summarized in Figure 12.
Figure 12. Features of SeaSpray DC Nebulizer.
Full length - thick walled VitriConeTM Sample Channel Machined exterior
Inert metal-free
argon connector
Instrumentspecific
provides optimum
aerodynamics
Polished “selfwashing”
“Direct
Connect” argon
line
UniFit sample tube
connector
Secure ratchet
connection
tip
Elegra - DuraMist DC - Twister - D-Torch
1.10
1.08
1.06
1.04
1.02
1.0
Normalized Intensity
To 0.98
evaluate the performance of the SeaSpray DC nebulizer a 1
ppm 0.96
multi-element standard was prepared in a 3.5 % NaCl matrix
and 0.94
0.92
aspirated at 1 mL/min for 9 hours with no rinsing. The test was
carried 0.9
out on an Agilent 5100 SVDV ICP-OES instrument. The
combination 19 25 of the 57 SeaSpray 89 DC 121 nebulizer,152 Twister 184 spray 216
chamber,
ceramic D-Torch, and Elegra Time argon (minutes)
humidifier provided exceptional
stability (Figure Ba 13).455.403 A measurement Mn 257.610 was taken approximately Zn 213.857
every
3 mins over a period of 9 hours, while a precision (%RSD) of less
than 1 % was maintained throughout the experiment.
Figure 13. Long term stability test, 9 hour analysis of 1 ppm standard in 3.5 % NaCl.
Elegra - SeaSpray DC - Twister - D-Torch
Wavelength Precision (% RSD)
Zn 213 0.8
Mn 257 0.6
Mg 280 0.6
19 78 153 228 303 378 453 528
Time (minutes)
1.10
1.08
1.06
1.04
1.02
1.0
0.98
0.96
0.94
0.92
0.9
Mg 280.270 Mn 257.610 Zn 213.857
Normalized Intensity
To complement the SeaSpray, the inert DuraMist nebulizer was
introduced in 2011.11 The DuraMist is also a concentric nebulizer,
designed with a PEEK capillary insert and PEEK body capable of
handling up to 30% TDS and up to 5% hydrofluoric acid (HF). The
strength and rigidity of the PEEK material allows the DuraMist to be
manufactured to very tight tolerances, enabling it to closely match
the performance of the SeaSpray, but in an inert design.
To evaluate the performance of the DuraMist DC nebulizer a similar
experiment was conducted, only this time a 1 ppm multi-element
standard was in a 10.0 % NaCl matrix and aspirated at 1 mL/min for 4
hours with no rinsing. The DuraMist DC nebulizer was combined with
the same “High TDS” application kit that was used in the SeaSpray
experiment, with a measurement taken every minute over a period of
4 hours (Figure 14). Results with the DuraMist are also exceptional,
as a precision (%RSD) of less than 1 % was maintained throughout
the experiment.
Figure 14. Long term stability test, 4 hour analysis of 1 ppm standard in 10.0 % NaCl.
Elegra - DuraMist DC - Twister - D-Torch
Wavelength Precision (% RSD)
Zn 213 0.8
Mn 257 0.5
Ba 445 0.9
19 25 57 89 121 152 184 216
Time (minutes)
1.10
1.08
1.06
1.04
1.02
1.0
0.98
0.96
0.94
0.92
0.9
Ba 455.403 Mn 257.610 Zn 213.857
Normalized Intensity
Reducing Sample Load and Increasing
Washout Efficiency
In our evaluation of Elegra the SeaSpray - SeaSpray and DC DuraMist - Twister -nebulizers D-Torch
a rinse
was not utilized in-between each sample. The rinse was purposely
eliminated from the ICP method to focus on each nebulizer’s high
tolerance to TDS. However, with any high TDS application it is
recommended that you increase your rinse time between samples
to provide improved performance and long term stability. It is also
recommended that you reduce the sample uptake rate to as low
as your detection limits allow to minimize the amount of sample
transported to the plasma. Lowering the sample uptake will reduce
the rate of devitrification to the quartz torch and frequency of cleaning
the ICP-MS cones.
However, longer rinse times combined with a lower sample uptake
can add significant time to your analysis. Some of this additional
time can be easily eliminated from your method with the Niagara
CM Rapid Rinse accessory (Figure 15), which begins rinsing the
nebulizer and spray chamber the instant the sample measurement is
completed and continues to rinse until the next sample is ready. This
economical and simple 4-port switching valve carries out the rinse
cycle during the time that is usually wasted waiting for the sample to
reach the nebulizer (commonly referred to as the uptake delay) and
subsequently void to waste. The fast pump option that is typically
employed to reduce the uptake delay time puts excess stress on
the nebulizer and ICP sample introduction system by running at high
flow rates that exceed the recommended operating conditions. With
the Niagara the fast pump can be employed with no negative effects,
since the sample is directed to waste during the uptake delay. The
Niagara rinse tubing calculator will also calculate the correct size
19 78 153 228 303 378 453 528
Time (minutes)
1.10
1.08
1.06
1.04
1.02
1.0
0.98
0.96
0.94
0.92
0.9
Mg 280.270 Mn 257.610 Zn 213.857
Normalized Intensity
www.geicp.com Glass Expansion Newsletter | Issue 43 5
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