Dissertação
Determinação de disruptores endócrinos em filé de peixe utilizando QuEChERS modificado e GC-(TQ)MS/MS
Fecha
2012-02-27Registro en:
MUNARETTO, Juliana Scariot. Determination of endocrine disrupters in fish fillet by modified QuEChERS and GC-(TQ)MS/MS. 2012. 145 f. Dissertação (Mestrado em Química) - Universidade Federal de Santa Maria, Santa Maria, 2012.
Autor
Munaretto, Juliana Scariot
Institución
Resumen
Endocrine Disrupter Compounds (EDCs) like pesticides, alkylphenols and hormones
among other classes of compounds are responsible for alterations in the endocrine
system functions. Endocrine disruption occurs when EDCs interact with the hormone
receptors, altering the natural response patterns of the endocrine system. Aquatic
organisms, such as fish, are able to accumulate EDCs residues in concentration
several times higher than the surrounding water. Consequently, fish is a major source
of contamination for both top predators and human consumers. This study aimed to
develop and validate a fast method for the determination of 40 endocrine disrupters
in fish fillet, using modified QuEChERS and Gas Chromatography coupled with Mass
Spectrometry in tandem, using a triple quadrupole analyzer (GC-(TQ)MS/MS). A
factorial design was performed to optimize the extraction procedure, which consist of
the extraction of 10.0 g of fish fillet with 10.0 mL of acetonitrile with 1% (v/v) of acetic
acid followed by manual shaking for 1 min. In the partition step 2.0 g of sodium
chloride, 1.7 g of anhydrous sodium acetate and 0.3 g of anhydrous magnesium
sulfate were added, followed by shaking and centrifugation at 3400 rpm for 8 min.
Then the extract was transferred to a 15 mL polypropylene tube containing the C18
and PSA sorbents, beyond the anhydrous magnesium sulfate. After shaking and
centrifuging, the supernatant was filtered and analyzed by GC-(TQ)MS/MS. The
method was validated by spiking the blank sample at three concentration levels (10,
25 and 50 Ug kg-1) obtaining recovery values between 70.1 to 120.0% for 36 of the
40 endocrine disrupters evaluated. RSD values below 20% ensured
the good precision of the method. The linearity was evaluated using the coefficient of
determination (r2) with values higher than 0.996 for all compounds. The matrix effect
was evaluated, and it was pretty intense for most compounds, with values exceeding
10%. This effect was compensated using analytical curves obtained with standards
prepared in blank matrix extracts. This method was applied in 6 samples of fish fillet
from different species. Residues of bisphenol A, chlorpyrifos and bifenthrin were
detected. Therefore, the modified QuEChERS method proved to be appropriated for
the determination of endocrine disrupters in fish fillet using GC-(TQ)MS/MS since it
showed to be effective and can be applied to routine analysis.