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| Author(s): |
Camila Rosa Moraes Vigna
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Química |
| Defense date: | 2010-02-06 |
| Examining board members: |
Carol Hollingworth Collins;
Anízio Márcio de Faria;
Sonia Claudia do Nascimento de Queiroz;
Maria Izabel Maretti Silveira Bueno;
Fabio Augusto
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| Advisor: | Carol Hollingworth Collins; Carla Beatriz Grespan Bottoli |
| Abstract | |
This work investigated the potentiality of use of sorbents and stationary phases (SP), obtained from the sorption and/or immobilization of poly(methyloctylsiloxane) (PMOS) onto the surface of a porous silica Kromasil support using heat, in the separation, quantification and validation of a methodology for analysis of agrochemicals in water and sugar cane samples. Physical-chemical characterization of the developed materials were carried out and applied in the concentration step of the samples in solid phase extraction (SPE) in off-line and on-line mode, with posterior separation, for High Performance Liquid Chromatography (HPLC) with UV-Vis detection. The QuEChERS method (Quick, Easy, Cheap, Effective and Safe) was also used as alternative in the extraction of the sugar cane samples. PMOS sorbents showed comparable performance to the commercial sorbents, with simple, fast and cheap preparation. The Kromasil/PMOS SP used demonstrated a good separation to the components of the samples of agrotoxics analyzed, similar to the commercial phases, with good efficiencies, resolution and selectivity. The developed methodology was validated and showed good results of recovery for the agrotoxics, with precision value < 15 % and correlation coefficient > 0,99. The limit of quantification (LQ) of the method allowed that the maximum residues limits (MRL) for the regulating agencies for all the studied compounds were reached. The developed and validated methods were applied in the analysis of sugar cane samples of the local commerce. Detectable levels of the agrochemicals studied in the analyzed samples were not detected (AU) | |