Department of Biophysics
Panjab University
As part of my work, I had to estimate zinc levels in colon tissue samples from dimethylhydrazine (DMH)-treated rats in order to study the efficacy and role of zinc in chemoprevention of colon carcinogenesis. Also, I wanted to check arsenic levels to study the protective effects of zinc during arsenic toxicity. I found the AAnalyst 200 Atomic Absorption Spectrometer to be sensitive, quick, and easy to operate.
The AAnalyst 200 is a true double beam spectrometer which features an Echelle optical system which helps compensate for changes in lamp intensity during analyses and stabilizes baseline operation. It has a highly sensitive solid state detector designed to provide high quantum efficiency in the UV region. With the help of the above features, it is possible to measure difficult elements like arsenic and barium with excellent signal-to-noise ratios. Further, the sampling compartment of the system is very spacious (25 by 25 cm) which allows easy access when changing the burner or nebulizer.
I was also impressed with the troubleshooting part of the instructions as they are written clearly on the instrument screen which eliminates cryptic numeric codes. It has a built-in cookbook which has recommended conditions for different elements thus allowing users to easily adjust the system for the element of interest. Data management by Winlab 32 software makes it more easy and efficient.
I analyzed trace elements in the colon as well as liver tissue samples. 100 mg of tissue were dissolved in perchloric acid/nitric acid (1:4) which was followed by heating on a sand bath for 44 hours. This lead to the formation of white ash which was dissolved in 5 ml of 10 mM nitric acid (HNO3). 1 ml of the above sample was analyzed using the AAnalyst 200. Samples were loaded by keeping them in special broad diameter glass tubes. The fine tube of nebulizer pipe was dipped into the glass tube, which then took the sample to the flame. One piece of advice for new users is this: the sample loading process in an atomic abruption spectrometer is fast, so you should be ready with all samples that need to be analyzed.
I found the Perkin Elmer atomic absorption spectrometer (AAnalyst 200) easily operable and the data management software is also user friendly. The only drawback of the AAnalyst 200 is its cost.