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This study evaluated acrylamide (AA) levels and various quality parameters in homemade fried potatoes prepared in different sizes by integrating principles from the Slow Food Movement with advanced sensor technology. To this aim, a surface plasmon resonance (SPR) sensor based on a molecularly imprinted polymer (MIP) was first developed for the determination of AA in homemade fried potatoes at low levels, and the AA levels in the samples were established. First of all, monolayer formation of allyl mercaptane on the SPR chip surface was carried out to form double bonds that could polymerize on the chip surface. AA-imprinted SPR chip surfaces modified with allyl mercaptane were prepared via UV polymerization using ethylene glycol dimethacrylate (EGDMA) as a cross-linker, N,N′-azobisisobutyronitrile (AIBN) as an initiator, and methacryloylamidoglutamicacid (MAGA) as a monomer. The prepared AA-imprinted and nonimprinted surfaces were characterized by atomic force microscopy (AFM) and Fourier transform infrared (FTIR) spectroscopy methods. The SPR sensor indicated linearity in the range of 1.0 × 10−9–5.0 × 10−8 M with a detection limit (LOD) of 3.0 × 10−10 M in homemade fried potatoes, and the SPR sensor demonstrated high selectivity and repeatability in terms of AA detection. Additionally, the highest AA level was observed in the potato sample belonging to the T1 group, at 15.37 nM (p < 0.05), and a strong and positive correlation was found between AA levels and sensory parameters, the a* value, the ΔE value, and the browning index (BI) (p < 0.05). [ABSTRACT FROM AUTHOR]

In this work, a new surface plasmon resonance (SPR) sensor based on sulphur-doped titanium dioxide (S-TiO2) nanostructures and molecularly imprinted polymer (MIP) was presented for thiram (THI) determination in milk samples. Firstly, the S-TiO2 nanomaterial with a high product yield was prepared by using a facile sol-gel hydrolysis technique with a high product yield. After that, UV polymerization was carried out for the preparation of the THI-imprinted SPR chip based on S-TiO2 using a mixture including ethylene glycol dimethacrylate (EGDMA) as the cross-linker, N,N′-azobisisobutyronitrile (AIBN) as the initiator, and methacryloylamidoglutamicacid (MAGA) as the monomer. The reliability of the sensor preparation procedure has been successfully proven by characterization studies of the prepared nanomaterials and SPR chip surfaces through spectroscopic, microscopic, and electrochemical methods. As a result, the prepared SPR sensor showed linearity in the range of 1.0 × 10−9–1.0 × 10−7 M with a detection limit (LOD) of 3.3 × 10−10 M in the real samples, and a sensor technique for THI determination with high sensitivity, repeatability, and selectivity can be included in the literature. [ABSTRACT FROM AUTHOR]

A new magnetic solid phase microextraction method (MSPE) was developed for the preconcentration of rhodamine B from plastics, cosmetics, and environmental samples before spectrophotometric analysis. A nanocomposite adsorbent containing ZnO nanoparticles (NPs), multi-walled carbon nanotubes (MWCNTs) and Fe3O4 nanoparticles was synthesized by a hydrothermal procedure. The new magnetic nanocomposite (MWCNTs@ZnO@Fe3O4) was characterized by Fourier-transform infrared spectroscopy (FT-IR), x-ray diffraction (XRD), and scanning electron microscopy (SEM). The pH, sample volume, eluent type, adsorbent mass, influence of foreign species, and analyte-adsorbent and eluent contact times were optimized. The optimum pH was 3; adsorbent mass, 20 mg; sample volume, 50 mL; and eluent, 0.7 mL of ethanol. Recovery values exceeding 95% were obtained. The developed vortex assisted magnetic solid phase extraction method (VA-MSPE) was applied to practical analysis. The limits of detection (LOD) and quantification (LOQ) were 0.83 µg L−1 and 2.77 µg L−1, respectively. The addition/recovery experiments were carried on several water samples to demonstrate acceptable recoveries. [ABSTRACT FROM AUTHOR]

This research attempt involved the development and utilization of a newly designed surface plasmon resonance (SPR) sensor which incorporated sulfur-doped graphitic carbon nitride (S-g-C3N4) as the molecular imprinting material. The primary objective was to employ this sensor for the quantitative analysis of Fenpicoxamid (FEN) in rice samples. The synthesis of S-g-C3N4 with excellent purity was achieved using the thermal poly-condensation approach, which adheres to the principles of green chemistry. Afterwards, UV polymerization was utilized to fabricate a surface plasmon resonance (SPR) chip imprinted with FEN, employing S-g-C3N4 as the substrate material. This process involved the inclusion of N,N′-azobisisobutyronitrile (AIBN) as the initiator, ethylene glycol dimethacrylate (EGDMA) as the cross-linker, methacryloylamidoglutamic acid (MAGA) as the monomer, and FEN as the analyte. After successful structural analysis investigations on a surface plasmon resonance (SPR) chip utilizing S-g-C3N4, which was imprinted with FEN, a comprehensive investigation was conducted using spectroscopic, microscopic, and electrochemical techniques. Subsequently, the kinetic analysis applications, namely the determination of the limit of quantification (LOQ) and the limit of detection (LOD), were carried out. For analytical results, the linearity of the FEN-imprinted SPR chip based on S-g-C3N4 was determined as 1.0–10.0 ng L−1 FEN, and LOQ and LOD values were obtained as 1.0 ng L−1 and 0.30 ng L−1, respectively. Finally, the prepared SPR sensor's high selectivity, repeatability, reproducibility, and stability will ensure safe food consumption worldwide. [ABSTRACT FROM AUTHOR]