Determination Of Prochloraz Research Articles

Development of a simple HPLC procedure for the determination of prochloraz residues in mushrooms

Abstract A simple HPLC-UV procedure is described in our paper which is suitable for the rapid and cost-efficient determination of prochloraz in mushrooms. Prochloraz is the only fungicide in EU which use is allowed in mushroom production. The aim of our work was the development of a simple method that is suitable for the control of this pesticide in everyday analyses during mushroom production. The procedure involves a simple sample preparation method based on solid-liquid extraction (modified QuEChERS extraction method EN 15662) followed by an HPLC-UV determination (recovery: 97–99%; limit of detection LOD: 0.01 mg/kg; limit of quantification LOQ: 0.05 mg/kg).

A beta-cyclodextrin-functionalized magnetic metal organic framework for efficient extraction and determination of prochloraz and triazole fungicides in vegetables samples

A β-cyclodextrin-functionalized magnetic zinc-metal organic framework (M-MOF/β-CD) was synthesized via a facile one-pot reaction. M-MOF/β-CD was used as a magnetic porous absorbent for the extraction and determination of prochloraz and three triazole fungicides in vegetable samples. M-MOF/β-CD was prepared by creating MOF layers on the surface of a Fe3O4–graphene oxide (GO) nanocomposite and bonding them with β-CD molecules. Characterization suggested that a 3D porous structure was formed, with M-MOF/β-CD exhibiting high superparamagnetism and a large surface area. As a new strategy, integrating MOFs with Fe3O4–GO could improve their water-resistance and mechanical strength by providing a rigid nanosupport interface. Combining M-MOF and β-CD resulted in excellent selective adsorption capacities for prochloraz and three triazole fungicides. The static adsorption process was evaluated and the results were in good agreement with the Freundlich model. Subsequently, M-MOF/β-CD was applied to extracting prochloraz and triazole fungicides from tomato and lettuce vegetables, followed by HPLC-MS/MS determination. The limits of detection for the above fungicides were found to be 0.25–1.0 μg/L at a signal-to-noise ratio of 3, with spiked recoveries of 74.13%–119.83%, indicating that M-MOF/β-CD was promising for application to the extraction and determination of fungicides in complex matrices.

Rapid Determination of Prochloraz in Orange Juice by Near-Infrared Spectroscopy

Near-infrared spectroscopy, which has advantages of high speed, high precision, and minimal sample preparation, is a rapid, solvent-free, on-site quantitative and qualitative analytical method. This study assessed the feasibility of using near-infrared spectroscopy to determine prochloraz residue in orange juice. Two chemometric methods, partial least-squares discriminant analysis and least-squares support vector machines, were employed to create mathematical models to classify three spectrum bands. The selected spectral values ranged from 5,030 to 5,100 cm−1. The results show the least-squares support vector model outperformed the discriminant analysis algorithm. Classification accuracy of 100% was obtained for the calibration set and the prediction set of the former when the two parameters, γ and σ2 were 20.5707 and 2.48703, respectively, while the classification accuracy of the discriminant analysis method for the calibration set and the prediction set were 100% and 96.8%, respectively. By contrast, it is easy to conclude that when the limit of detection of the proposed method is set as low as 0.5 µg mL−1, the support vector model has the capability to predict the presence or absence of prochloraz residue, whereas the discriminant analysis model may give false positives. Considering the analytical process for a sample takes only about one minute, the proposed method ensures the simplicity and reliability in practical applications. The results of the study showed the potential of near-infrared spectroscopy as a rapid and environmentally friendly method for the on-site screening of prochloraz in orange juice.

Determination of Prochloraz and Its Metabolites in Fruits and Vegetables by GC

An analytical method was developed for prochloraz and its metabolites. Each fruit or vegetable was homogenized and then extracted with acetone followed by re-extraction with ethyl acetate. The extract was transferred into a glass ampoule and pyridine hydrochloride was added. The ampoule was sealed and heated at 200°C for 3hrs. Prochloraz and its metabolites were converted into 2, 4, 6-trichlorophenol (2, 4, 6-TCP), dissolved in 0.2mol/L HCl and extracted with hexane, then 2, 4, 6-TCP was determined by using GC. The recoveries from Japanese radish, white rape, tomato, mandarin orange and Chinese citron were 85.5%, 79.9%, 70.9%, 71.3% and 67.1%, respectively. The determination limit was 0.02μg/g for prochloraz in these samples.