NEWS
IsoMist:
The temperature of a sample introduction system has a profound
effect on the performance of an ICP-OES and an ICP-MS. A
cooled spray chamber is often used to reduce the volatility of
certain solvents so that the plasma is sustained. Heating the spray
chamber results in higher sample transport. Maintaining the spray
chamber temperature can be critical when trying to achieve longterm
signal stability.
Figure 2a: IsoMist Programmable Temperature Spray Chamber
The IsoMistTM Programmable Temperature Spray Chamber
(Figure 2A) is a convenient and universal device for both controlling
and monitoring the spray chamber temperature. The temperature
is electronically controlled using a powerful inbuilt Peltier device,
allowing the ICP analyst to select any temperature between -10oC
and +60oC in 1oC increments to provide the optimum conditions for
any application.
Unique to the IsoMist is a Twister spray chamber encapsulated
with a temperature conductive resin (Figure 2B). The encapsulated
spray chamber provides a uniform temperature from top to bottom
and an air tight fit within the IsoMist module to prevent condensation
build-up and freezing (Figure 2C). These unique features of the
IsoMist allow for a stable temperature to be held within +/- 0.1oC
and a temperature of -5oC to be reached within 15 minutes. Other
Tracey cyclonic spray chamber:
The Tracey cyclonic spray chamber is Glass Expansion’s standard
glass cyclonic spray chamber (50 mL volume). It gives the best
sensitivity and lowest memory effects for standard ICP analyses.
The typical application uptake range is 0.2 to 3.0 mL/min.
Twister cyclonic spray chamber:
The Twister cyclonic spray chamber features a central transfer tube
which acts as a secondary droplet filter to reduce the mean droplet
size. This reduces solvent load in the plasma without compromising
detection limits, while improving precision (% RSD). The typical
application uptake range is 0.2 to 3.0 mL/min.
Low volume spray chamber:
Glass Expansion offers two low volume spray chamber designs,
the CinnabarTM and TwinnabarTM . The advantage of a low volume
spray chamber is to provide a very fast washout for sample uptake
rates in the range of 20 to 400 μL/min. The Cinnabar is a minicyclonic
based on the Tracey design while the Twinnabar is minicyclonic
based on the Twister design. Like the Twister, the center
baffle of the Twinnabar offers a reduced solvent load and excellent
precision, in addition to a very fast washout.
PTFE and PFA spray chamber:
In 2006, Glass Expansion released a new line of PTFE and PFA
spray chambers which have an internal surface that is specially
treated using a proprietary process, named StediflowTM , to improve
the wettability of the surface and provide consistent drainage.
Without the Glass Expansion Stediflow treatment, droplets tend to
form on the surface and degrade both sensitivity and precision.
Glass Expansion offers two styles of HF-resistant spray chambers,
the Tracey TFE and PFA44. The Tracey TFE is made from PTFE
(Teflon) which is more chemically resistant than the old polypropylene
HF-resistant spray chamber. The Tracey TFE spray chamber can
be teamed with the DuraMist HF-resistant nebulizer to form the
ideal chemically inert sample introduction system for ICP-OES. The
Tracey PFA44 is made from ultra-pure PFA to provide exceptional
purity and excellent sensitivity for ICP-MS techniques. The PFA44
spray chamber can be teamed with the OpalMist PFA nebulizer
to form the highest purity, most inert sample introduction system
available. A Tracey PFA44 spray chamber molded specifically for an
airtight fit within the IsoMist module, is provided to those customers
who require an HF-resistant temperature controlled option. Further
details on the IsoMist are covered in the following section.
Figure 2b: IsoMist Glass Twister Spray Chamber encapsulated in conductive resin
www.geicp.com Glass Expansion Newsletter | Issue 35 2
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