Development and evaluation of extraction methods and chromatographic separation for determination of triazine, ureas and uracil herbicides in soil and water samples.

• Grant number: 11/08309-5
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: October 01, 2011
• End date: September 30, 2015
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Analytical Chemistry
• Principal Investigator: Jorge Cesar Masini
• Grantee: Ricardo de Prá Urio
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Substantial fraction of herbicides used in the agriculture reaches the soil, an environmental compartment where these substances are liable to processes of adsorption, degradation, leaching, etc. The control of environmental quality requires efficient and low cost analytical methods. After sampling, sample treatment processes including extraction, pre-concentration and elimination of interferences are extremely important, because they influence the quality of the results. The extraction of pesticides from soil samples is still done predominantly in Soxhlet systems, employing time-consuming procedures that consume large volumes of solvent. Strategies for efficient and rapid extraction assisted by ultrasound or microwave have been described, but still using substantial amounts of solvents or expensive instrumentation. An alternative procedure that does not use organic solvents is the cloud point extraction, which has been exploited for extraction, purification and pre-concentration of various pesticides. Currently, great attention has been given to the extraction process called QuEChERS, which aims, as its acronym suggests, be Quick, Easy, Cheap, Effective, Rugged and Safe. In this project we intend to explore cloud point extraction and QuEChERS procedures followed by separation techniques using HPLC (High Performance Liquid Chromatography) and SIC (Sequential Injection Chromatography) with different stationary phases for the determination of the herbicides of the classes of triazines, ureas and uracil in soils and water samples. Among the triazines, emphasis will be given to simazine, ametryne metribuzin, atrazine and metabolites. Among ureas, linuron, tebuthiuron and dinuron will be studied. Bromacil will be selected as representative of the uracil class. The goal of this project is the development of efficient and low cost methods of analysis with minimum waste generation. Extraction procedures based on Soxhlet and ultrasound will be used as a reference methods.

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

URIO, RICARDO P.; MASINI, JORGE C.. Evaluation of Monolithic and Core-Shell Columns for Separation of Triazine Herbicides by Reversed Phase High Performance Liquid Chromatography. Journal of the Brazilian Chemical Society, v. 26, n. 11, p. 2331-2338, NOV 2015. (13/18507-4, 11/08309-5)

URIO, RICARDO DE PRA; MASINI, JORGE C.. Evaluation of sequential injection chromatography for reversed phase separation of triazine herbicides exploiting monolithic and core-shell columns. Talanta, v. 131, p. 528-534, JAN 2015. (11/08309-5)

URIO, RICARDO DE PRA; INFANTE, CARLOS M. C.; MASINI, JORGE C.. Online Sequential-Injection Chromatography with Stepwise Gradient Elution: A Tool for Studying the Simultaneous Adsorption of Herbicides on Soil and Soil Components. Journal of Agricultural and Food Chemistry, v. 61, n. 33, p. 7909-7915, AUG 21 2013. (11/08309-5)

URIO, RICARDO DE PRA; MASINI, JORGE CESAR. Determination of Simazine and Atrazine in River Water by Cloud-Point Extraction and High-Performance Liquid Chromatography. Analytical Letters, v. 50, n. 7, p. 1065-1074, 2017. (13/18507-4, 11/08309-5)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

URIO, Ricardo de Prá. Development and evaluation of extraction and chromatographic methods in monolithic and core-shell columns for determination of triazine herbicides in soils and waters. 2015. Doctoral Thesis - Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ) São Paulo.