Coating of Sol–Gel Film on Silver Nanodendrite as a Novel Solid-Phase Microextraction Fiber for Determination of Volatile Aldehydes in Edible Oils

Abstract

In this work, a novel solid-phase microextraction fiber was fabricated by a new substrate applied for quantitative analysis of trace volatile aldehydes emitted during thermal oxidation of edible oils, analyzed by GC–MS. Ag nanodendrites as a porous substrate, spontaneously coated on a Cu wire, and polydimethylsiloxane/polyethylene glycol (PDMS/PEG) were deposited onto the substrate by sol–gel dip-coating. Parameters affecting the extraction efficiency, such as the substrate porosity, extraction time and temperature, and desorption time and temperature were investigated and optimized. The desorption temperature was chosen as 260 °C, and desorption time was set at 3 min. Results shows that extraction efficiency of sol–gel coating deposited on Ag nanodendrite substrate is meaningfully higher than that of deposited on bare Cu wire. Under the optimum conditions, the limits of detection (LODs) ranged between 0.5 to 0.2 μg/L. The relative standard deviations including repeatability (within fibers) and reproducibility (between fibers) varied between 7.5–11.2 and 9.3–16.2%, respectively.