Dispersive liquid‐liquid microextraction method combined with sugaring‐out homogeneous liquid‐liquid extraction for the determination of some pesticides in molasses samples

Abstract

In this study, a sensitive analytical method was developed to determine some pesticides (cyprodinil, trifloxystrobin, prometryn, propachlor, fenitrothion, chlorpyrifos, profenofos, and phosalone) in molasses samples. Pesticides were extracted from samples by dispersive liquid‐liquid microextraction method combined with sugaring‐out homogeneous liquid‐liquid extraction and determined by gas chromatography–mass spectrometry analysis. In this method, pesticides in molasses samples were first extracted using a water‐miscible solvent (acetonitrile) in the sugaring‐out homogeneous liquid‐liquid extraction stage. The sugar in the ratio of 84–88% naturally contained in the molasses sample enabled phase separation in the acetonitrile‐water homogeneous mixture. Then acetonitrile phase containing pesticides was used as dispersing solvent in the second step of the process. Under the specified optimum conditions, the limit of detection was calculated between 0.8–6.1 ng/g and the limit of quantification was in the range of 2.5–20 ng/g. The relative standard deviation values of molasses samples containing 150 ng/g of each analyte were found to be lower than 4.9% intra‐day and 5.6% for inter‐day. This validated method has been successfully applied to different types of molasses.

Matrix‐induced sugaring‐out liquid‐liquid microextraction coupled with high‐performance liquid chromatography for the determination of organophosphorus pesticides in fruit jams

“…Under the same conditions, aliquots of 1 g cherry jam sample were added with 1 ml of solvent/water mixture (50/50%, v/v) and subjected to vigorous shaking (1 min at 2500 rpm) and centrifuged at 6000 rpm for 4 min. The visual observations (Figure S1) showed that only ACN formed a two-phase system, while other solvents could not be separated from the aqueous solution, a result which is consistent with findings from several studies [16,19,20]. Therefore, ACN was selected as a water-miscible solvent for further studies.…”

“…The SULLME-HPLC/UV method is compared with recent methods reported in the literature [20,[27][28][29][30][31][32] for the determination of OPPs in some food samples, taking into account some performance parameters such as time required for basic operations, LOD, RSD, and recovery. Comparison details are summarized in Table 3.…”

“…In this sense, honey is an ideal sample that can be analyzed with SULLME, as its chemical composition consists of approximately 77% mono‐ and oligosaccharides [17]. Similarly, molasses is the other sugar‐rich food (84–88%) that has found application in the SULLME for the extraction of multiclass pesticides [20].…”

“…Another advantage of ACN, associated with being the most popular mobile phase in LC, is that its final extract can be directly analyzed [7]. The SULLME has been used for extracting analytes of varied polarity, e.g., drugs [9,[11][12][13], phenolic compounds [10], bioactive constituents [14,15], bisphenols [16], sulfonamides [17], and pesticides [18][19][20] from biological and/or food matrices. Glucose is most often preferred as a sugaring-out reagent, since it is cheap, easily available and efficient, and produces a less viscous solution [12].…”

Combination of microwave‐assisted solvent extraction and effervescence‐assisted deep eutectic solvent‐based in‐syringe dispersive liquid‐liquid microextraction and its application in the extraction of triazine pesticides from apple samples

“…Up to now, much attention has been paid to this field and different sample preparation methods have been introduced. Among these methods, dispersive liquid-liquid microextraction (DLLME), that has been introduced in 2006 to overcome the problems associated with conventional liquid-liquid extraction (being tedious and consuming high volumes of toxic organic solvents), has gained an outstanding position [11,12]. In this approach, the extraction solvent is dispersed throughout the sample solution by means of a dispersive solvent, and the analytes are extracted into the produced fine droplets of extractant [13].…”