Improving the Berthelot reaction for determining ammonium in soil extracts and water

被引:373
作者
Rhine, ED
Sims, GK
Mulvaney, RL
Pratt, EJ
机构
[1] ARS, USDA, Urbana, IL 61801 USA
[2] Univ Illinois, Dept Nat Resources & Environm Sci, Urbana, IL 61801 USA
关键词
D O I
10.2136/sssaj1998.03615995006200020026x
中图分类号
S15 [土壤学];
学科分类号
0903 ; 090301 ;
摘要
Colorimetric methods based on the Berthelot reaction are used widely for quantitative determination of NH4-N in biological and environmental samples. Studies to evaluate phenol and salicylate, the most commonly used chromogenic substrates, revealed minor interferences by metallic cations, whereas up to a threefold shift in absorbance was observed with 38 diverse N-containing organic compounds. Interferences differed markedly between phenol and salicylate. The possibility of a simple correction was precluded by the fact that interferences were both positive and negative, and depended on the temperature during color development and the concentration of NH4-N. Fourteen compounds were evaluated as alternatives to phenol and salicylate, of which the Na salt of 2-phenylphenol (PPS) proved to be the most promising. Using PPS, macro-and microscale batch methods and an automated flow-injection method were developed. These methods are simple, convenient, and sensitive. Using the PPS microscale method, for which the limit of detection is 0.17 mg NH4-N L-1, recovery of NH4-N added to soil extracts ranged from 98 to 104%, with a coefficient of variation of 1.4 to 2.7%. As with phenol and salicylate, precipitation of metal hydroxides was observed. Precipitation was controlled by chelation with citrate rather than ethylenediaminetetraacetic acid (EDTA), which suppressed color development by preventing monochloramine formation. Compared with Berthelot methods that use phenol or salicylate, interference by amino acids was decreased by up to 10-fold. Interference by other organic N compounds was virtually eliminated.
引用
收藏
页码:473 / 480
页数:8
相关论文
共 22 条
[1]   AMINO-ACID INTERFERENCE WITH AMMONIUM DETERMINATION IN SOIL EXTRACTS USING THE AUTOMATED INDOPHENOL METHOD [J].
BURTON, DL ;
GOWER, DA ;
RUTHERFORD, PM ;
MCGILL, WB .
COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS, 1989, 20 (5-6) :555-565
[2]   DETERMINATION OF AMMONIUM IN KJELDAHL DIGESTS OF CROPS BY AN AUTOMATED PROCEDURE [J].
CROOKE, WM ;
SIMPSON, WE .
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, 1971, 22 (01) :9-&
[3]  
FORGANSMITH J, 1976, CLIN CHIM ACTA, V69, P139, DOI 10.1016/0009-8981(76)90485-X
[4]   ANALYSIS OF AMMONIA IN POLLUTED SEA-WATER [J].
HAMPSON, BL .
WATER RESEARCH, 1977, 11 (03) :305-308
[5]  
Keeney D. R., 1982, AGRON MONOGR, P643, DOI DOI 10.2134/AGR0NM0N0GR9.2.2ED.C33
[6]   RE-EXAMINATION OF THE DETERMINATION OF AMMONIUM AS THE INDOPHENOL BLUE COMPLEX USING SALICYLATE [J].
KEMPERS, AJ ;
KOK, CJ .
ANALYTICA CHIMICA ACTA, 1989, 221 (01) :147-155
[7]   Accelerated diffusion methods for inorganic-nitrogen analysis of soil extracts and water [J].
Khan, SA ;
Mulvaney, RL ;
Mulvaney, CS .
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL, 1997, 61 (03) :936-942
[8]   ANALYSIS OF ORGANIC NITROGEN COMPOUNDS .12. A SPECTROPHOTOMETRIC METHOD FOR DETERMINATION OF AMMONIA NITROGEN BY USE OF HYPOCHLORITE AND 2-METHYL-8-HYDROXYQUINOLINE [J].
MORITA, Y ;
KOGURE, Y .
NIPPON KAGAKU ZASSHI, 1970, 91 (07) :653-&
[9]  
MORITA Y, 1963, NIPPON KAGAKU ZASSHI, V84, P816
[10]  
Mulvaney R.L., 1996, METHODS SOIL ANAL, P1123, DOI DOI 10.2136/SSSABOOKSER5.3.C38