Development of a new stir bar sorptive extraction coating and its application for the determination of six pesticides in sugarcane juice

Abstract

In this article, a novel polydimethylsiloxane/activated carbon (PDMS-ACB) material is proposed as a new polymeric phase for stir bar sorptive extraction (SBSE). The PDMS-ACB stir bar, assembled using a simple Teflon(®)/glass capillary mold, demonstrated remarkable stability and resistance to organic solvents for more than 150 extractions. The SBSE bar has a diameter of 2.36 mm and a length of 2.2 cm and is prepared to contain 92 μL of polymer coating. This new PDMS-ACB bar was evaluated for its ability to determine the quantity of pesticides in sugarcane juice samples by performing liquid desorption (LD) in 200 μL of ethyl acetate and analyzing the solvent through gas chromatography coupled with mass spectrometry (GC-MS). A fractional factorial design was used to evaluate the main parameters involved in the extraction procedure. Then, a central composite design with a star configuration was used to optimize the significant extraction parameters. The method used demonstrated a limit of quantification (LOQ) of 0.5-40 μg/L, depending on the analyte detected; the amount of recovery varied from 0.18 to 49.50%, and the intraday precision ranged from 0.072 to 8.40%. The method was used in the analysis of real sugarcane juice samples commercially available in local markets.

Stir-bar sorptive extraction: 15 years making sample preparation more environment-friendly

“…Other sorbent materials {e.g., poly(phthalazine ether sulfone ketone) (PPESK), polypyrrole (PPY), and polyacrylate (PA) [10,17,62,63]} were also proposed as SBSE sorbent coatings, some prepared through the immersion-precipitation technology, where PPESK exhibited high thermal stability (290ºC), long lifetime and promoted good enrichments, mainly for semi-polar and polar compounds.…”

Advances in stir bar sorptive extraction coating: A review

“…A novel polydimethylsiloxane/activated carbon (PDMS/ACB) material is proposed as a new polymeric phase for stir bar sorptive extraction by Barletta et al [47]. This new PDMS-ACB bar was used to determine quantity of pesticides (carbofuran, atrazine, metribuzine, ametryn, tebuthiuron, and bifenthrin) in sugarcane juice samples.…”

Extraction and stirring integrated techniques: examples and recent advances

“…In [18] this case, the PDMS is mixed with the modifier and an elastomer curing agent, avoiding bubble formation. The resulting mixture is introduced into a polytetrafluoroethylene (PTFE) mold in which a magnetic rod has previously been located, and submitted to controlled thermal treatment to form the desired coating.…”

“…The resulting mixture is introduced into a polytetrafluoroethylene (PTFE) mold in which a magnetic rod has previously been located, and submitted to controlled thermal treatment to form the desired coating. By use of this procedure, stir-bars based on PDMS and polypyrrole (PPY) [17] or activated carbon (ACB) [18] have been prepared. The PDMS-PPY coating has high porosity and efficiency compared with PDMS, enabling efficient extraction of anti-depressants from plasma, with excellent extraction recovery despite the complexity of the matrix.…”