Journal
MICROCHEMICAL JOURNAL
Volume 94, Issue 1, Pages 79-82Publisher
ELSEVIER
DOI: 10.1016/j.microc.2009.09.005
Keywords
Nitrate; Nitrite; Simultaneous determination; Flow injection analysis; Soil
Categories
Funding
- Science and Technology Council of Argentina (Universidad Nacional de Santiago del Estero)
Ask authors/readers for more resources
Spectrophotometric flow injection methods were developed for the individual determination of nitrite or nitrate, and for the simultaneous determination of nitrite and nitrate, in soil samples. Nitrite was determined directly using a modified version of the Griess-Ilosvay diazo-coupling reaction, measuring at 543 nm the absorbance of the azo-dye complex formed. Simultaneous nitrite and nitrate determinations were based on on-line nitrate reduction in a micro column containing copperised cadmium. A single chromogenic reagent containing all the necessary reactants was used in both methods. For determinations, the chemical and instrumental variables were optimised by univariate analysis and simplex chemometric method. The optimised conditions gave a linear calibration range between 0.05 and 1.6 mu g m L-1 for N-NO2- and between 0.05 and 7.0 mu g m L-1 for N-NO3-. The detection limits for nitrite and nitrate were 22 mu g L-1 and 44 mu g L-1 respectively. The proposed methods allowed up to 35-40 samples per hour to be analysed with good precision. The simultaneous method was successfully used for the determination of nitrite and nitrate in soil samples (the results obtained were validated against those obtained by reference methods). The proposed methods are simpler and faster than conventional methods and could be routinely used in environmental monitoring laboratories. (C) 2009 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available