Electrospun Nanofibers Modified with Copper Nanoparticles for Simultaneous Extraction and Detection of Three Ochratoxins in Foods

In this study, several electrospun nanofibers were prepared and characterized, and the electrospun polystyrene/poly(ether sulfone) nanofiber coated with copper nanoparticles (PS/PES-CuNP nanofibers) was selected and utilized as solid-phase extraction adsorbent. And then, the packed-fiber solid-phase extraction coupled with high-performance liquid chromatography-fluorescence detection method was established for the efficient determination of ochratoxins in foods. With the proposed method, several factors including the type and dosage of nanofibers, sample pH, extraction time, type, and volume of elution solvent were optimized. The results suggested that low limit of detection (0.102–0.126 ng/mL), limit of quantification (0.382–0.436 ng/mL), and recoveries (85.5–111.1%) for ochratoxin A, B, and C with relative standard deviations <7% were achieved. As-synthesized PS/PES-CuNP nanofibers displayed satisfactory potential practical application in the simultaneous pretreatment and determination of mycotoxins in complex matrice samples

Data of adsorption amount normalized to that of Tenax TA.

<p>Data of adsorption amount normalized to that of Tenax TA.</p

SEM images: (A) PS nanofibers (A1, 2K×; A2, 10K×); (B) AR nanofibers (B1, 2K×; B2, 10K×); (C) PS-AR nanofibers (C1, 2K×; C2, 10K×); (D) Tenax TA (D1, 800×; D2, 5K×).

<p>SEM images: (A) PS nanofibers (A1, 2K×; A2, 10K×); (B) AR nanofibers (B1, 2K×; B2, 10K×); (C) PS-AR nanofibers (C1, 2K×; C2, 10K×); (D) Tenax TA (D1, 800×; D2, 5K×).</p

System of electrospinning.

<p>System of electrospinning.</p

Variation in the response of samples adsorbed on (A) PS-AR nanofibers and (B) Tenax TA maintained at different temperatures.

<p>Variation in the response of samples adsorbed on (A) PS-AR nanofibers and (B) Tenax TA maintained at different temperatures.</p

Data of thermal desorption rates of VOCs normalized to that of Tenax TA.

<p>Data of thermal desorption rates of VOCs normalized to that of Tenax TA.</p

Linearity of response-amount of the target compounds in water curves.

<p>Linearity of response-amount of the target compounds in water curves.</p

Experimental devices: 1. Vacuum pump; 2. Ventilation tube; 3. Gas cylinder; 4. Rubber plug; 5. Sealing clip; 6. Stainless steel wire; 7. Sample flask; 8. Sample box; 9. Aluminum foil; 10. Magnetic stir bar; 11. Magnetic stirrer.

<p>Experimental devices: 1. Vacuum pump; 2. Ventilation tube; 3. Gas cylinder; 4. Rubber plug; 5. Sealing clip; 6. Stainless steel wire; 7. Sample flask; 8. Sample box; 9. Aluminum foil; 10. Magnetic stir bar; 11. Magnetic stirrer.</p

Thermal desorption rates of VOCs at 1.5 mL or 10 mL headspace volume.

<p>Thermal desorption rates of VOCs at 1.5 mL or 10 mL headspace volume.</p

Summation (μg/5 mg) of the target VOCs by thermal and solvent desorption.

<p>Summation (μg/5 mg) of the target VOCs by thermal and solvent desorption.</p