Issue: Số 25 - Tháng 9 - 2026Hóa học - Công nghệ thực phẩm
Development of a semi-quantitative test kit for urea analysis in fertilizer samples
Published: October 3, 2026
Abstract
This study investigates the analytical conditions, validates the analytical method, develops a semi-quantitative test kit for urea in urea-containing fertilizer samples, and evaluates the greenness of the analytical procedure. The results show that the colored compound formed between urea and 4-dimethylaminobenzaldehyde in a strongly acidic HCl medium becomes stable after 5 minutes of reaction and remains color-stable for up to 40 minutes. The resulting compound exhibits maximum absorbance at 420 nm. The analytical method has a linear range of 5 - 700 mg/L, with a limit of detection (LOD) of 0.5 mg/L and a limit of quantification (LOQ) of 1.6 mg/L. The repeatability, expressed as %RSD, is 0.741%, while the recovery ranges from 99% to 102%. The test kit was developed for urea concentrations ranging from 80 to 700 mg/L. The analytical procedure demonstrates high reliability, meets the requirements for semi-quantitative urea analysis, and shows a relatively favorable green profile based on an assessment against the 12 principles of Green Analytical Chemistry.
Keywords
ureatest kitanalytical conditionsurea fertilizer
References
1.
Gunasekaran S. and Sivakumar S. (1996). Studies on Nitrogen Assimilatory Enzymes of Rice Plants Inoculated with Azospirillium Strains. Indian Journal of Microbiology, 36, 223-225.
2.
Zayed O., Hewedy O.A, Abdelmoteleb A. et al (2023). Nitrogen Journey in Plants: From Uptake to Metabolism, Stress Response, and Microbe Interaction.. Biomolecules, 13(10), 1443. doi: 10.3390/biom13101443.
Ohyama T. (2010). Nitrogen as a major essential element of plants. 2010, 1-18.
4.
Ilya O. 2019. Chapter 33 - Basics of Biochemistry, Radiation: Elsevier, 399-427.
5.
Kun-hsiang L., Yajie N., Mineko K. et al (2017). Discovery of nitrate–CPK–NLP signalling in central nutrient–growth networks. Nature, 545, 311-316. doi: 10.1038/nature22077.
Towards Chemicals And Materials. Global Urea Market Report: Strategic Analysis and Forecast (2025-2035) [Online] Available at: https://www.linkedin.com/pulse/global-urea-market-report-strategic-analysis-a6q0c. [Accessed 11 May 2026].
7.
Menconi D. E. (1985). Determination of urea in fertilizers using ion chromatography coupled with conductometric detection. Analytical Chemistry, 57(8), 1790-1792. doi: 10.1021/ac00285a071.
Lorenzo Q., Serena L., Claudio C. et al (2023). Electrochemical methods for the determination of urea: Current trends and future perspective. TrAC Trends in Analytical Chemistry, 168, 117345. doi: https://doi.org/10.1016/j.trac.2023.117345.
Karpukhina E. A, Khromov G. A, Volkov D. S et al (2024). Determination of Urea and Humate in Humate Fertilizers Using ATR FTIR Spectroscopy. Journal of Analytical Chemistry, 79(12), 1764-1772. doi: 10.1134/S1061934824701338.
Langenfeld N. J, Payne L. E, and Bugbee B. (2021). Colorimetric determination of urea using diacetyl monoxime with strong acids. PLoS One, 16(11), e0259760. doi: 10.1371/journal.pone.0259760.
Wilding M. H and Blanton E. L (2002). Spectrophotometric determination of urea in ammonium nitrate fertilizers. Journal of Agricultural and Food Chemistry, 30 (3), 596-598. doi: 10.1021/jf00111a045.
Yin L., Yu L., Guoet Y. et al (2024). Green analytical chemistry metrics for evaluating the greenness of analytical procedures. Journal of Pharmaceutical Analysis, 14(11) 101013. doi: https://doi.org/10.1016/j.jpha.2024.101013.
Gałuszka A., Migaszewski Z., and Namieśnik J. (2013). The 12 Principles of Green Analytical Chemistry and the SIGNIFICANCE Mnemonic of Green Analytical Practices. TrAC, Trends Anal. Chem., 50, 78.
14.
AOAC Official Methods of Analysis (2016). Guidelines for Standard Method Performance Requirements, Appendix F.
