Atomic absorption spectrometer A-2

Flame atomizers are designed to work with the following mixtures::

• acetylene – air;
• acetylene – nitrous oxide;
• propane-butane mixture - air.

The device is controlled using a personal computer with the Microsoft Windows®operating system.

The A-2 atomic absorption spectrometer is equipped with two background radiation correction systems: the deuterium system and the Smith-Hifty system (correction by self-rotation of the spectral line).

Wavelength adjustment, peak search procedure, adjustment of the spectral slit width, switching of spectral lamps, adjustment of the height and position of atomizers are performed automatically. For various measurement modes, the software contains sets of pre-configured parameters, and these sets of parameters can be reconfigured by the user in accordance with the methodological instructions for conducting a specific analysis. These changes can be written to a file (as well as calibration curves) and called up again if necessary. Switching between flame and electrothermal atomizers is performed automatically.

Measurements in both modes can be performed using an autosampler.

The measurement method is based on the selective absorption of electromagnetic radiation by the atoms of the element being determined in the gas phase.

The A-2 atomic absorption spectrometer can be used for research in almost any laboratory, including the laboratories of the following institutes:

• state control and supervision system;
• food processing industry;
• ecology;
• medicine and pharmacology;
• geology and mining industry;
• metallurgy industry;
• pulp and paper industry;
• chemical and petrochemical industry;
• production of mineral fertilizers;
• criminalistics and forensic medical examination;
• scientific research;
• biotechnology;
• and many other areas.

Main objects of analysis

flame atomization mode:

• natural and waste water;
• ambient and work area air;
• soils and bottom sediments;
• steels and alloys;
• biological objects.

electrothermal atomization mode:

• drinking and natural waters;
• atmospheric air;
• soils and bottom sediments;
• food products (grain and grain products, fish, eggs, milk and dairy products, products of the fat and oil and meat processing industries);
• mixed feed;
• alcoholic products;
• steels and alloys;
• biological objects, including: whole blood, blood serum, hair, nails, and liver tissue.

Some examples of methodological support for analysis objects

• metals in the soil: RD 52.18.685-2006 and RD 52.18.286-91;
• mercury in the soil: PNDF 16.1:2.3:3.10-98 and MUK 4.1.1472-03;
• natural water: RD 52.24.377-2008, RD 52.24.479-2008, RD 52.44.594-97;
• drinking water: GOST R 51212-98, GOST R 51309-99;
• drinking, natural and waste water: HDPE F 14.1: 2:4.137-98 (Dew), HDPE F 14.1:2:4.138-98, HDPE F 14.1:2:4.139-98, HDPE F 14.1:2:4.140-98.

Some typical examples of tasks to be solved

• determination of Fe, Mn, Co, Cu, Zn, Ni, K, Na, Ca, Mg concentrations in natural and wastewater samples;
• determination of Ag, Al, As, Be, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Se, Sn, Sr, V, and Zn concentrations in drinking water samples;
• determination of Cd, Cu, Co, Cr, Mn, Ni, Fe, Sn, Se, Pb, Zn concentrations in food samples: meat, fish, offal, sausage and sausage products, eggs and dairy products;
• determination of Cd, Cu, Pb, Mn, Ni, Co, As, Hg, Cr, Zn, and Sb concentrations in soils and bottom sediments.

The current regulatory framework of control and analytical laboratories implies the presence of two devices for conducting atomic absorption analysis, one with a flame atomization method, the other with an electrothermal one.

The combination of two atomization methods in the A-2 atomic absorption spectrometer, fast switching from one mode to another, allows you to use one device, significantly reducing the cost of purchasing and operating equipment.

The use of two atomization methods in the A-2 atomic absorption spectrometer makes it possible to determine the content of elements in a wide range of concentrations: from 0.5 mcg/l (when operating in the electrothermal atomization mode) to 5000 mcg/l (when operating in the flame atomization mode).

The advantages of the device include some technical solutions implemented both in the design of the spectrometer itself and in additional equipment.

Device as a whole:

• fast change of atomizers (3 minutes);
• automatic change of turret-type lamps (turret) for 8 positions;
• automatic control of setting the wavelength and intensity of the radiation source;
• automatically set and change the width of the selected spectral interval ("slit width");
• application of two methods for correcting non-selective absorption: deuterium correction and Smith-Hifty correction;
• ability to install automatic input devices (autosamplers);
• possibility of installing a mercury-hydride attachment.

Electrothermal atomization unit:

• the service life of a graphite furnace (cuvette) is not less than 500 atomizations;
• autonomous cooling system;
• transverse heating of a modified graphite furnace (cuvette) with a pyrolytic coating and "end caps", which in turn leads to such positive moments:
• no "memory effect";
• good reproducibility of the analysis results (relative measurement error of 0.5-2% for pure solutions and 1-5% for complex samples);
• low element detection limits.

Flame atomization unit:

• corrosion-resistant spray system and burner materials;
• high efficiency of aerosol formation of solutions;
• automatic adjustment of the burner position and height;
• control and automatic adjustment of the fuel gas and oxidizer supply speed;
• automatic flame ignition and extinguishing system;
• silent operation of the compressor.

Software:

• compatible with Windows;
• sets the parameters of the spectrometer and automatically changes atomizers;
• monitors the current status of all spectrometer units and set-top boxes;
• allows for 9-stage heating of a graphite furnace;
• allows you to save analysis results in various formats, generate reports, and print them out;
• guarantees safety when working with the spectrometer.

Hollow cathode spectral lamps:

The A-2 atomic absorption spectrometer can be equipped with a different set of spectral lamps, depending on the tasks solved by the customer's laboratory.

Autosampler

The specialized autosampler is designed to work with the A-2 atomic absorption spectrometer.

It has the ability to automatically select standard solutions, analyzed samples, enter chemical modifiers and auxiliary solutions when the AAS operates in the electrothermal atomization mode.

Also, this autosampler supports entering samples into the flame atomizer.

Characteristics in electrothermal mode

• Up to 76 vials are placed in the sample tray (10 for standard solutions, 60 for analyzed samples, and 6 for matrix modifiers).
• Capacity of the sample or standard solution vials: 1.5 ml.
• Capacity of the modifier bottle: 12 ml.
• Reproducibility – less than 2%.
• Dilution function: the maximum multiplier in the case of dilution is 120, and the linearity is at least 0.995.
• Modifier input function.
• Sample shaking function.
• Low pressure protection function: if the argon pressure drops to 0.2 MPa, the flushing is disabled and an error message is displayed on the PC display.

Characteristics in flame mode

• Up to 38 vials are placed in the sample tray (6 for standard solutions, 32 for analyzed samples).
• Sample vial capacity: 6 ml.
• Capacity of the standard solution vials: 12 ml.
• Reproducibility: for copper (Cu) - less than 0.6 % (flame: acetylene-air).
• Reproducibility: for copper (Cu) - less than 1.0 % (flame: propane-butane mixture-air).
• Reproducibility: for barium (Ba) – less than 1.0 % (flame: acetylene-nitrous oxide).
• Low pressure protection function: if the argon pressure drops to 0.2 MPa, the flushing is disabled and an error message is displayed on the PC display.