PRODUCTS
Shimadzu News 3/2003
AA-6300 for
multi-element analysis with
system validation
Fully automatic atomic absorption spectrometer –
determination of cadmium, copper and arsenic
T
he quantitative determination of main, transition and
trace elements is part of the
daily routine analyses in every
control laboratory. These types
of analysis are carried out presently using modern atomic absorption spectrometers, for example
Shimadzu’s new AA-6300.
with optimized surface. The system is therefore resistant to all
known acids, organic solvents and
reagents that are commonly used
in atomic absorption spectrometry.
Background correction
Two standard background correction methods are available for reliable determination of trace elements in complex matrices in the
flame- and graphite furnace mode.
• The deuterium technique for
correction of spectral interferences caused by molecular
absorption and light scattering
caused by particles
• The high current pulse technique
(high speed self reversal method),
which can correct interferences
caused by absorption line overlapping and structured background.
The determination of
cadmium and copper
AA-6300 with GFA-EX7i and autosampler
An important criterion for effective sample throughput is fully
automatic operation. Current system configuration enables the
determination of a maximum of 20
elements in an analysis sequence
for 60 individual samples in flame
or electrothermal atomisation.
Very long analyses sequences, for
example in unattended overnight
operation or during online operation, require regular system validation during quality control of
measurement and test equipment.
high performance operation and is
designed for trace analysis.
900 nm and consists of a CzernyTurner monochromator with a
holographic grating (1800 lines/
mm). The detector system, consisting of a photomultiplier for a
wavelength range of 185 - 600 nm
and a Si-detector for wavelengths
between 600 and 900 nm, offers
For flame atomisation, the new
AA-6300 is equipped with a titanium burner, a ceramic impact bead,
a platinum/iridium capillary and a
polypropylene spray chamber
PRODUCTS
Shimadzu News 3/2003
The highly efficient nebulisation
unit combined with the stable
optical system leads to excellent
performance data of approximately 0.350 Abs for a copper
solution at a concentration of
2 mg/L and a detection limit of
0.0015 mg/L. Table 1 lists the
instrumental parameters for the
quantitative determination of cad-
mium and copper. Both sets of
parameters are loaded automatically from the system and are
processed sequentially. The background correction method is
selected according to the element
analysed:
• for copper the deuterium technique is used
• for cadmium, due to the known
spectral interference of iron, the
deuterium technique typically
leads to overcompensation.
Therefore, the high-speed selfreversal technique is used.
The calibration curve for cadmium
in a concentration range of 0.04
mg/L up to 0.1 mg/L is shown in
Figure 2.
High Sensitivity
required!
The graphite furnace mode has
been used successfully for many
years for the trace analysis of
heavy metals, for instance arsenic,
cadmium, lead and manganese.
Growing environmental awareness
as well as increased quality
requirements and control mechanisms on our daily needs (such as
drinking water) lead to almost
unimaginable, constantly more
refined and increasingly more
accurate analytical methods. The
Environmental Commission of the
0.500
0.100
0.400
All experimental work described
below has been carried out on a
Shimadzu AA-6300 system, which
is equipped for electrothermal
atomisation using a GFA-EX7i
graphite furnace with fully automatic sample preparation station
(Figure 1). The spectrometer operates in a wavelength range of 185 -
0.200
324.8
Slit width (nm)
1.0
0.5
Atomisation
Flame
Flame
Lamp current D 2 BGC*(mA)
–
6
Lamp current SR BGC**(mA) 8/100
–
Acetylene (L/min)
1.8
1.9
Table 1: Instrumental parameters
**Deuterium background correction
for the determination of the elements
**Self reversal background correction
copper and cadmium.
Element
Pb
As
Mn
Wavelength (nm)
283.3
193.7
279.5
Slit width (nm)
0.7
0.7
0.2
Atomisation
Furnance
Furnance
Furnance
Lamp current D 2 BGC*(mA)
–
–
10
Lamp current SR BGC**(mA) 8/300
12/400
–
Ashing (°C)
800
600
800
Atomisation (°C)
2400
2200
2200
Matrix Modifier
Pd (NO 3) 2
Pd (NO 3) 2
–
Table 2: Instrumental parameters
**Deuterium background correction
for the determination of the elements
**Self reversal background correction
arsenic, lead and manganese.
European Union decided on 11
March 1999 to again lower drastically the threshold values for
heavy metals. The actual value of
50 micrograms of lead per litre
was decreased to 10 micrograms
per litre as lead can cause damage
to the nervous system in small
children and pregnant women. In
2003, the new drinking water law
was ratified and water supply
companies as well as regulatory
agencies are now required to analyse the chemical parameters
according to the new threshold
values in compliance with Appendix 2 Part II of the drinking water
regulation.
0.025
0.100
0.000
0.000
0.025
0.050
0.075
0.100
0.000
0.000
2.500
5.000
7.500
10.000
12.500 15.000
Conc. (ppb)
Conc. (mg/L)
Figure 2: Calibration curve for cadmium
2
Cu
228.8
The determination
of arsenic, lead and
manganese
Abs.
Abs.
0.300
0.050
Cd
Wavelength (nm)
1000 mg/L 1000 mg/L
0.075
System
requirements
Element
17.500
20.000
The digital temperature control of
the new GFA-EX7i graphite furnace allows optimisation of the
system characteristics with high
signal intensities at excellent
reproducibility. The system is also
intelligent enough to differen- Figure 3: Calibration curve for lead
3
PRODUCTS
Shimadzu News 3/2003
AA-6300 for
multi-element analysis with
system validation
Fully automatic atomic absorption spectrometer –
determination of cadmium, copper and arsenic
T
he quantitative determination of main, transition and
trace elements is part of the
daily routine analyses in every
control laboratory. These types
of analysis are carried out presently using modern atomic absorption spectrometers, for example
Shimadzu’s new AA-6300.
with optimized surface. The system is therefore resistant to all
known acids, organic solvents and
reagents that are commonly used
in atomic absorption spectrometry.
Background correction
Two standard background correction methods are available for reliable determination of trace elements in complex matrices in the
flame- and graphite furnace mode.
• The deuterium technique for
correction of spectral interferences caused by molecular
absorption and light scattering
caused by particles
• The high current pulse technique
(high speed self reversal method),
which can correct interferences
caused by absorption line overlapping and structured background.
The determination of
cadmium and copper
AA-6300 with GFA-EX7i and autosampler
An important criterion for effective sample throughput is fully
automatic operation. Current system configuration enables the
determination of a maximum of 20
elements in an analysis sequence
for 60 individual samples in flame
or electrothermal atomisation.
Very long analyses sequences, for
example in unattended overnight
operation or during online operation, require regular system validation during quality control of
measurement and test equipment.
high performance operation and is
designed for trace analysis.
900 nm and consists of a CzernyTurner monochromator with a
holographic grating (1800 lines/
mm). The detector system, consisting of a photomultiplier for a
wavelength range of 185 - 600 nm
and a Si-detector for wavelengths
between 600 and 900 nm, offers
For flame atomisation, the new
AA-6300 is equipped with a titanium burner, a ceramic impact bead,
a platinum/iridium capillary and a
polypropylene spray chamber
PRODUCTS
Shimadzu News 3/2003
The highly efficient nebulisation
unit combined with the stable
optical system leads to excellent
performance data of approximately 0.350 Abs for a copper
solution at a concentration of
2 mg/L and a detection limit of
0.0015 mg/L. Table 1 lists the
instrumental parameters for the
quantitative determination of cad-
mium and copper. Both sets of
parameters are loaded automatically from the system and are
processed sequentially. The background correction method is
selected according to the element
analysed:
• for copper the deuterium technique is used
• for cadmium, due to the known
spectral interference of iron, the
deuterium technique typically
leads to overcompensation.
Therefore, the high-speed selfreversal technique is used.
The calibration curve for cadmium
in a concentration range of 0.04
mg/L up to 0.1 mg/L is shown in
Figure 2.
High Sensitivity
required!
The graphite furnace mode has
been used successfully for many
years for the trace analysis of
heavy metals, for instance arsenic,
cadmium, lead and manganese.
Growing environmental awareness
as well as increased quality
requirements and control mechanisms on our daily needs (such as
drinking water) lead to almost
unimaginable, constantly more
refined and increasingly more
accurate analytical methods. The
Environmental Commission of the
0.500
0.100
0.400
All experimental work described
below has been carried out on a
Shimadzu AA-6300 system, which
is equipped for electrothermal
atomisation using a GFA-EX7i
graphite furnace with fully automatic sample preparation station
(Figure 1). The spectrometer operates in a wavelength range of 185 -
0.200
324.8
Slit width (nm)
1.0
0.5
Atomisation
Flame
Flame
Lamp current D 2 BGC*(mA)
–
6
Lamp current SR BGC**(mA) 8/100
–
Acetylene (L/min)
1.8
1.9
Table 1: Instrumental parameters
**Deuterium background correction
for the determination of the elements
**Self reversal background correction
copper and cadmium.
Element
Pb
As
Mn
Wavelength (nm)
283.3
193.7
279.5
Slit width (nm)
0.7
0.7
0.2
Atomisation
Furnance
Furnance
Furnance
Lamp current D 2 BGC*(mA)
–
–
10
Lamp current SR BGC**(mA) 8/300
12/400
–
Ashing (°C)
800
600
800
Atomisation (°C)
2400
2200
2200
Matrix Modifier
Pd (NO 3) 2
Pd (NO 3) 2
–
Table 2: Instrumental parameters
**Deuterium background correction
for the determination of the elements
**Self reversal background correction
arsenic, lead and manganese.
European Union decided on 11
March 1999 to again lower drastically the threshold values for
heavy metals. The actual value of
50 micrograms of lead per litre
was decreased to 10 micrograms
per litre as lead can cause damage
to the nervous system in small
children and pregnant women. In
2003, the new drinking water law
was ratified and water supply
companies as well as regulatory
agencies are now required to analyse the chemical parameters
according to the new threshold
values in compliance with Appendix 2 Part II of the drinking water
regulation.
0.025
0.100
0.000
0.000
0.025
0.050
0.075
0.100
0.000
0.000
2.500
5.000
7.500
10.000
12.500 15.000
Conc. (ppb)
Conc. (mg/L)
Figure 2: Calibration curve for cadmium
2
Cu
228.8
The determination
of arsenic, lead and
manganese
Abs.
Abs.
0.300
0.050
Cd
Wavelength (nm)
1000 mg/L 1000 mg/L
0.075
System
requirements
Element
17.500
20.000
The digital temperature control of
the new GFA-EX7i graphite furnace allows optimisation of the
system characteristics with high
signal intensities at excellent
reproducibility. The system is also
intelligent enough to differen- Figure 3: Calibration curve for lead
3
PRODUCTS
Shimadzu News 3/2003
tiate the heating rates for each set
temperature, for instance for lead
(slow heating rates up to approximately 800 °C and fast heating rate
at 2400 °C so that the preset atomisation temperature can be reached
within a fraction of a second).
This leads to results as shown in
Figure 3 for the calibration of lead
in the measuring range of 5 mg/L
up to 20 mg/L where the concentration of the new threshold value
(10 mg/L) is straight within the
ideal calibration range.
water sample with a certified
arsenic concentration of 0.72 mg/L
± 0.05 mg/L was used as control
standard. The concentration measured with the GFA-EX7i was
0.73 mg/L (average value from 3
determinations) and is in excellent
agreement with the certified reference value.
0.200
0.150
0.100
System validation
0.050
0.000
The temperature step between the
thermic pretreatment (ashing
phase) and atomisation must be as
small as possible in order to reach
the final temperature selected as
quickly as possible and to avoid a
strong expansion of the inert gas.
The digital gas control ensures that
the flow through the graphite tube
during atomisation and also the
last 3 to 5 seconds of the ashing
phase can be stopped reproducibly
in order to avoid premature release
of the atomic cloud and to increase
the residence time of the atoms in
the light path. The instrumental
parameters are listed in Table 2.
Arsenic is another element which
is significant in environmental
analysis because of its toxicity.
Arsenic can be determined quantitatively using AAS analysis in the
hydride and graphite furnace
mode in samples such as drinking
water, mineral water, wastewater
and sludge, each with its associated matrix problems. Modern
0.0
2.5
Figure 4: Typical absorption signal for
an arsenic standard sample
graphite furnace systems such as
the GFA-EX7i enable reliable routine determination of an arsenic
concentration of 1 mg/L, using a
suitable background correction
technique such as the high-speed
self-reversal method. This method
for the determination of arsenic
using graphite furnace atomic
absorption spectrometry is
described in DIN 38405-35 in the
German Standard Methods
(Deutsche Einheitsverfahren) for
routine analysis.
Figure 4 shows a typical absorption signal for an arsenic standard
sample at a concentration of
6 mg/L, obtained using the digital
graphite furnace. The element
signal (red) and the background
signal (blue) of 3 repeated measurements are overlayed as peak
profiles. An international reference
Atomic absorption spectrometry is
a relative technique for the quantification of element concentrations, so the calibration curve as
the important basic requirement
for accurate measurement must be
obtained prior to analysis of
unknown samples. The quality of
the calibration can be tested during routine operation using reference materials as control standards. Regular control of the analysis sequence using control standards is a standard function of the
system software. The system validation during quality control
however requires the use of a software package which is independent of the system software.
Parameters tested during system
validation are wavelength accuracy, baseline noise and drift, as
well as performance data of selected elements in the flame and
graphite furnace atomisation mode
and calculation of the detection
limits. A basic requirement for
accurate measurement is the precise setting of the element-specific
wavelengths.
Using a slit width of 1 nm, the
profile of the selected line is registered and the energy maximum is
set. Setting of the wavelength may
not exceed the predetermined tolerance limits, otherwise a wavelength calibration procedure must
be carried out. Testing of the wavelength in the range of 253.7 up to
640.2 nm is shown in Figure 5.
The set wavelength is at 640.20 nm
with a standard deviation of 0.02
nm within the tolerance limits.
The first semi-micro balance
with UniBloc technology
Always optimally
calibrated
Testing of additional
critical parameters
Similarly, additional critical parameters can be tested, for instance
the stability of the system. The
drift of light sources used for element- and background absorption
may not exceed predetermined
threshold values in order to guarantee the high quality of the analytical data over extended periods
of operation. Additionally it is
necessary to carry out regular control of the performance data in
absorption, i.e. testing the sensitivity of the system and to assure
excellent reproducibility of repeated measurements. It is of course
important to use suitable control
standards. Testing of the performance data in the flame mode using
a copper standard is shown in Figure 6.
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PRODUCTS
Shimadzu News 3/2003
High-performance measuring cell for
the fully automatic semi-micro AUW-D
analytical balance series
S
himadzu’s AUW-D series
represents a special highlight
in the newest developments
of analytical and semi-micro balances. The AUW-D series consists
of fully automatic semi-micro/
analytical balances in the dualrange operational mode. This
means that the balances can be
operated up to a maximum weighing capacity of 82 g at a display
accuracy of 0.01 mg and up to
220 g at an accuracy of 0.1 mg.
PSC is a fully automatic calibration function of the balance that
responds to changes in the ambient temperature. An internal sensor determines the temperature
variations and initiates a fully
automatic calibration as soon as a
certain tolerance level is reached.
This way, the balance is optimally
calibrated at any time. In addition,
the so-called ‘Clock-Cal’ function
can be used. The user can predefine up to three individual times
per day at which the balance is
automatically calibrated, for example at the start of the working day,
at noon and in the evening. This
guarantees that the balance is
operational at any time, even without the presence operating personal.
Of course, the balance can be calibrated at any other time the user
wishes – just by pushing the button. Calibration with external
weights is also extremely simple.
In this case a weight is placed on
the balance and the user simply
follows the instructions on the
display.
Special
applications?
such as a set for density determination, an external printer, footoperated switch and external keyboard for simple data entry, is
optional.
All balances are equipped with a
serial interface, which can transfer
data via a zero-modem cable
directly into a Windows application. Additional software is not
necessary. Shimadzu’s patentedpending ‘WindowsDirect’ function
makes the use of its balances very
comfortable. With respect to FDA
21 CFR Part 11 requirements, the
data can be transferred directly to
the CLASS
Agent software,
which complies
with the FDA
requirements.
Specific software offers
various options
to adjust the
instrument
depending on
the ambient
conditions at
the site of operation. Via
options such as
‘Anti-Wind, ‘Anti-Vibration’ et
cetera, the balances can be operated under non-optimal conditions.
racy of 0.1 mg. They offer a
weighing capacity of 120 g – max.
320 g and feature a variety of
accessories. Balances in the AUW
series also feature a backgroundilluminated display, which significantly enhances readability in dark
areas. Depending on the model,
PSC, Clock-Cal and an internal
automatic calibration weight are
implemented.
In general, Shimadzu’s wide selection of balances offers individual
solutions at an excellent price/
quality ratio.
AUW-series balances are accurate up
to five decimal points
Shimadzu NEWS, Customer Magazin of Shimadzu Deutschland GmbH, Duisburg
Publisher:
Design and Production:
Shimadzu Deutschland GmbH
ME Werbeagentur GWA · Düsseldorf
Albert-Hahn-Str. 6 -10 · 47269 Duisburg
Telefon: +49 (0) 203 76 87-0
Telefax: +49 (0) 203 76 66 25
Email:
[email protected]
Internet: www.shimadzu.de
Editorial Team:
All models in the AUW-D series
are equipped with the high-performance UniBloc measuring cell.
This guarantees very fast equilibration times and accurate, stable
results. The balances feature userfriendly functions, such as ‘Perfect
Self-Calibration’ (PSC), Clock-Cal
and an integrated motor-driven
calibration weight.
Circulation:
7.300 Copies
© Copyright:
Shimadzu Deutschland GmbH, Duisburg,
September 2003.
Uta Steeger
Windows is a Trademark of Microsoft
Telefon: +49 (0) 203 76 87- 410
Corporation.
Ralf Weber, Adlene Berg
Figure 5: Testing of the wavelength
In order to handle the numerous
functions that a modern balance
must perform, various applications
(for instance piece counting, measurement of specific densities and
various units such as ct, g, mg...)
are integrated into the software.
Switching between applications is
possible at the touch of a button.
The extensive range of accessories,
Analytical balances
of the AU series
In addition to the semi-micro balances of the dual-range series,
Shimadzu also offers a wide range
of classical analytical balances. The
AUW/AUX and AUY series are
all equipped with UniBloc technology and feature a display accu-
Figure 6: Testing of the performance
data in the flame mode
4
5