Atomic absorption (AA) has been known since the 19th century, but it was not until the 1950s, thanks to efforts by Alan Walsh at Australia’s CSIRO research center, that use of AA spectrometers became routine for metals analysis.
Four Fast Facts on AA Spectrophotometers
• AA measures ultraviolet light absorbed by hot, atomized metals. The absorbance wavelength is unique to every metal, but the signal intensity varies by concentration. Instrumentation is straightforward, consisting of a light source, atomizer and detector.
• AA handles many sample types, but operation requires that metal analytes exist as freestanding atoms in the gas state, rather than as ions in solution or solid metals or salts. Solution samples must first be dried, a process known as “desolvation,” before they are atomized and pumped with UV light.
• This type of spectrophotometer is useful in applications such as: environmental analysis; quality control for contaminant, ingredient, or trace metal in foods, drugs, personal care products, paper, materials, and other products; forensics, archeology, mining, agriculture; and natural science experimentation.
• Interesting developments in AA include the introduction of the single xenon arc lamp, which permits a single light source or instrument to address all metals accessible by AA. Similarly, the introduction of solid-state charge-coupled device detectors, improved background detection, direct analysis of solids (without atomization), and the ability to detect nonmetals has extended the capabilities of modern AA spectrophotometers.
Top 6 Questions You Should Ask When Buying an AA spectrophotometer
1. Ask if it’s possible to have a sample run on the instrument you’re considering for purchase and how long will it take.
2. Can the company’s AA spectrophotometer perform both flame and furnace analyses, and what are the detection limits for each?
3. What type of post-sale application and technical support does the company offer and how much will it cost?
4. What is the typical time-frame from original purchase order to installation?
5. Are there any plans to introduce a new instrument in the near future and, if so, can the current one be upgraded?
6. What can the company tell you about the total cost of ownership, including expected consumables, software upgrades, service, and warranty costs?
Recently Released AA spectrophotometers
• 3-D optical system is capable of producing maximum performance for both flame detection (Pb 0.015 ppm) and furnace detection (Pb 0.00005 ppm)
• Features improved lower limits of detection for furnace analysis in all fields, as compared to Shimadzu’s previous series designs
• Has a very small footprint
• Shipped ready for use
• Features a hands free ignition for added safety
• All operating conditions are pre-loaded in the internal computer
• The three lamp turret has individual controls for alignment and standby mode to keep lamps warm
• Rugged design handles tough matrices
• Modular parts are easily replaced so there is no downtime
• WinLab32™ for AA software combines ease-of-use with greater flexibility to provide a high level of productivity
• Designed with input from lab managers and AA users around the world, instrument provides all the tools and features needed to quickly start running samples
• Flame and graphite furnace is integrated into one instrument
• Change over from one technique to another is carried out by simple key strokes within the software • Spectral bandwidth is automated and is available with choice of five slit sizes
• Computer controlled heating program allows user to select the best heating program for analysis
A & E Lab
AA spectrophotometer Manufacturers
A & E Lab www.aelabcn.com
Analytik Jena www.analytik-jena.com
Aurora Biomed www.aurorabiomed.com
Buck Scientific www.bucksci.com
GBC Scientific www.gbcscientific.com
Hitachi High Technologies www.hitachi-hta.com
PG Instruments www.pginstruments.com
Thermo Fisher Scientific www.thermoscientific.com