Combination of fabric phase sorptive extraction with UHPLC-ESI-MS/MS for the determination of adamantine analogues in human urine

Chemometric Optimization of SPE for the Determination of Multiclass Pesticides in Portable Water Samples by UHPLC-MS/MS

This study aimed on the development of a SPE-UHPLC-MS/MS method for the simultaneous determination of pesticide residues in drinking water samples. A chemometric approach was applied to optimize the efficiency of the SPE pretreatment procedure. This study involved (i) the application of a Full Factorial Design for the screening of the significant factors, (ii) the application of a Central Composite Design for the determination of the optimal conditions and (iii) the evaluation and validation of the significance of the statistically proposed models. Oasis HLB cartridges were used for the extraction. The optimum sample volume was 300 mL and the elution solvent 3 mL of the mixture of methanol:ethylacetate 70:30 v/v. The method was validated according to the international guidelines. Recoveries were ranged from 63 to 116% and the detection limits were between 0.1 and 1.5 pg mL- 1. The validated method could be used in routine analysis for pesticides screening.

Design and development of second-generation fabric phase sorptive extraction membranes: Proof-of-concept for the extraction of organophosphorus pesticides from apple juice prior to GC-MS analysis

In this work, different sol-gel sorbent-coated second-generation fabric phase sorptive extraction (FPSE) membranes were synthesized using titania-based sol-gel precursors. The proposed membranes were tested for their efficiency to extract eleven selected organophosphorus pesticides (OPPs) from apple juice samples. Among the examined materials, sol-gel C₁₈ coated titania-based FPSE membranes showed the highest extraction efficiency. These membranes were used for the optimization and validation of an FPSE method prior to analysis by gas chromatography-mass spectrometry. The detection limits for OPPs ranged between 0.03 and 0.08 ng mL^-1. Moreover, the relative standard deviation was < 8.2% and 8.4% for intra-day and inter-day studies, respectively. The relative recoveries were 91-110% (intra-day study) and 90-106% (inter-day study) for all the target analytes, demonstrating good overall method accuracy. Moreover, the novel membranes were reusable at least 5 times. The titania-based membranes were compared to the conventional silica-based membranes and their utilization resulted in higher extraction recoveries.

Magnet Integrated Fabric Phase Sorptive Extraction for the Extraction of Resin Monomers from Human Urine Prior to HPLC Analysis

In this work, a method for the simultaneous determination of four resin monomers: Bisphenol A, bisphenol A methacrylate glycidate, triethyleneglycol-dimethacrylate, and urethane dimethacrylate, from human urine using magnet integrated fabric phase sorptive extraction (MI-FPSE), followed by high performance liquid chromatography (HPLC) diode array detection (HPLC-DAD), is presented. MI-FPSE is a novel configuration of FPSE that incorporates the stirring and extraction mechanism into one device, resulting in an improved extraction kinetic factor. FPSE is a green sample preparation technique that uses a flexible surface, such as cellulose, coated with a polymeric material using sol–gel technology. Poly(tetrahydrofuran) (PTHF) material was selected, due to its higher efficiency in terms of recovery rate among the studied MI-FPSE membranes. Optimization of the extraction process was performed based on several extraction and elution parameters. The method was validated for its linearity, selectivity, accuracy, precision, and stability of the samples. For the four compounds, the LOD and LOQ were 0.170 ng/μL and 0.050 ng/μL, respectively. The relative standard deviation of the method was less than 9.8% and 11.9%, for the within-day and between-day precision, respectively. The relative recoveries were between 85.6 and 105.2% in all cases, showing a good accuracy. The effectiveness of the proposed method was confirmed through successful application to the bioanalysis of real urine samples.

Fabric phase sorptive extraction-gas chromatography-mass spectrometry for the determination of favipiravir in biological and forensic samples

Favipiravir, a pyrazine analog, is proposed as providential antiviral agent against the COVID-19 infection during 2020 pandemic emergency. For the first time, a fabric phase sorptive extraction (FPSE) combined with gas chromatography-mass spectrometry (GC-MS) has been developed and applied for the determination of favipiravir (FAV) in biological samples (human plasma, blood and urine), pharmaceutical and forensic samples. The method comprises of extraction of FAV by FPSE followed by its derivatization with N, O-bis (trimethylsilyl) trifluoroacetamide (BSTFA) and GC-MS analysis. Design of experiment-based optimization was performed using Placket-Burman Design (PBD) and Central Composite Design (CCD) for the screening of significant factors of FPSE and their optimization, respectively. Among all tested membranes, sol-gel polyethylene glycol (PEG) has offered the best extraction efficiency for FAV. Under optimum conditions, the proposed method was found to be linear in the range of 0.01–10 µg mL⁻¹ by GC-MS. The LODs and LOQs were as low as 0.001-0.0026 μg mL⁻¹ and 0.003-0.0086 μg mL⁻¹, respectively by GC-MS. Intra-day and inter-day precisions were less than 5 and 10 %, respectively, showing good method precision. The proposed method has been successfully applied to detect and quantify FAV in human urine, whole blood and plasma samples along with seized forensic samples. In addition, the proposed method has been evaluated for its green character by ComplexGAPI index.

Designing an "all-in-one" microextraction capsule device for the liquid chromatographic-fluorescence determination of doxorubicin and its metabolites in rat plasma

In this study, an "all-in-one" microextraction device was designed and fabricated for the extraction of doxorubicin and its two metabolites from rat plasma prior to their determination by high performance liquid chromatography coupled to fluorescence detector. A sol-gel-based sorbent was synthesized in situ and incorporated within two conjoined porous polypropylene tubes together with a cylindrical magnetic bar in order to avoid the need of an external stirring bar. Among other sorbents investigated, the moderately polar sol-gel poly(tetrahydrofuran) was found to be advantageous due to its high affinity toward the target analytes. Systematic investigation of the critical parameters affecting the adsorption and the desorption step was carried out. Due to the "built-in" filtration mechanism of the porous microextraction capsules, the isolation of the analytes was performed directly in the plasma matrix without any previous sample pretreatment (i.e., protein precipitation, centrifugation, etc.). The proposed method was validated in terms of linearity, accuracy, precision, specificity, sensitivity, and stability according to the FDA guidelines. The limits of detection ranged between 1 - 2 ng mL^-1 while the lower limits of quantitation of the analytes were calculated as 10 ng mL^-1. The accuracy (% relative error) was found within -9.7 - 15.3% under both intra- and inter-day conditions. The precision was better than 13.4% in all cases. ComplexGAPI index was employed to present the green attributes of the developed protocol from the preparation of the microextraction device to the final determination of the analytes. Finally, the applicability of the fabricated stand-alone extraction device was demonstrated in the analysis of the target analytes in rat plasma after intravenous administration of doxorubicin in order to assess its pharmacokinetic profile.

Fabric phase sorptive extraction combined with gas chromatography-mass spectrometry as an innovative analytical technique for the determination of selected polycyclic aromatic hydrocarbons in herbal infusions and tea samples

This study presents a fabric phase sorptive extraction (FPSE) protocol for the isolation and preconcentration of four selected polycyclic aromatic hydrocarbons from tea samples and herbal infusions, followed by their separation and quantification by gas chromatography-mass spectrometry (GC-MS). In FPSE, extraction of the target analytes is performed utilizing a flexible fabric substrate that is coated with a highly efficient sol–gel sorbent. In this work, eighteen different FPSE membranes were examined, with the highest extraction recoveries being observed with the sol–gel C₁₈ coated FPSE membrane. The main parameters that influence the adsorption and desorption of the PAHs were optimized and the proposed method was validated. The detection limits and the quantification limits were 0.08–0.17 ng mL⁻¹ and 0.25–0.50 ng mL⁻¹, respectively, for the different target compounds with a 10 mL sample. The relative standard deviations for intra-day and inter-day repeatability were less than 7.9% and 8.5%, respectively. The sol–gel C₁₈ coated FPSE membrane could be used for at least 5 subsequent sample preparation cycles. Finally, the proposed protocol was successfully employed for the determination of PAHs in a wide range of tea and herbal infusion samples.

A fabric phase sorptive extraction (FPSE) protocol for the isolation and preconcentration of four selected polycyclic aromatic hydrocarbons from tea samples and herbal infusions is presented, followed by their quantitative analysis by GC-MS.