New HPLC and Fluorometric Methods for the Determination of Pyriproxyfen and Pyridalyl Insecticide Residues in Tomatoes

Farouk, Maha; Hussein, Lobna A.; Azab, Noha F. El

doi:10.5740/jaoacint.12-354

Cited by 8 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, the JMPR also reported t 1/2 values for pyriproxyfen of 6.4–36 days in aerobic soils, 16–21 days in aerobic lake sediments and 3.72–6.36 days for photo‐degradation under artificial light 18 . In the present study, the t 1/2 of pyriproxyfen on fresh tea leaves was 2.74 days, shorter than that of other crops reported in the literature and slightly longer than the t 1/2 of 2.1 and 2.59 days on tomato 43 . These results highlight the differences in pyriproxyfen dissipation rate among different crops.…”

Section: Resultscontrasting

confidence: 67%

“…The dissipation of pesticides on different crops is affected by many factors, such as the physical and chemical properties of the pesticides, the crop varieties, the geographic environment and other external conditions. To date, there have been many studies of pyriproxyfen residue dissipation on different crops; its t 1/2 has been reported as 13.3 days in citrus, 22 13.3 days in peach 23 ; 5.41 days, 20 2.1 days, 2.59 days 43 and 11.3 days 44 in tomato; 5.41 days in green pepper 20 ; and 18.57 days in pepper 21 . Differences in t 1/2 for pyriproxyfen on tomato may have been caused by different climates, environments, and other conditions at the different study sites.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Residue degradation, transfer and risk assessment of pyriproxyfen and its metabolites from tea garden to cup by ultra performance liquid chromatography tandem mass spectrometry

et al. 2022

View full text Add to dashboard Cite

BACKGROUND Tea is one of the most popular drinks in the world. The growth of tea plant is inseparable from the control of pesticides on diseases and pests. Pyriproxyfen is used as a pesticide substitute to control insect pests in tea gardens, but little is known about its residue degradation. Here, we performed an integrative study of the degradation and metabolism of pyriproxyfen from the tea garden to the cup. RESULTS The dissipation half‐life of pyriproxyfen during tea growth was 2.74 days, and five metabolites PYPAC, PYPA, DPH‐Pyr, 5′′‐OH‐Pyr, and 4′‐OH‐Pyr were generated. The total processing factors for pyriproxyfen in green tea and black tea were 2.41–2.83 and 2.77–3.70, respectively. The residues of pyriproxyfen and its metabolites were affected by different processing steps. The total leaching rates of pyriproxyfen from green tea and black tea into their infusions were 9.8–12.3% and 5.3–13.8%, respectively. The leaching rates of the five metabolites were higher than that of pyriproxyfen and increased the intake risk. CONCLUSION To ensure safe consumption, the recommended maximum residue limit value of pyriproxyfen in tea can be set to 5 mg kg−1 and the pre‐harvest interval can be set to 5 days. © 2022 Society of Chemical Industry.

show abstract

Section: Resultscontrasting

confidence: 67%

Section: Resultsmentioning

confidence: 99%

Residue degradation, transfer and risk assessment of pyriproxyfen and its metabolites from tea garden to cup by ultra performance liquid chromatography tandem mass spectrometry

et al. 2022

View full text Add to dashboard Cite

show abstract

“…e classical manners for determining pyriproxyfen along with another pesticide in agriculture products like fruits and vegetables are gas chromatography-mass spectrometry [6] and liquid chromatography-mass spectrometry [7]. Moreover, many papers were published for the estimation of pyriproxyfen with other pesticides by high-performance liquid chromatography and HPLC with UV detection [8,9]. Ultraperformance liquid chromatography coupled with tandem mass spectrometry is also used for determination of pyriproxyfen [10].…”

Section: Introductionmentioning

confidence: 99%

Three Different Spectrophotometric Methods for Simultaneous Determination of Pyriproxyfen and Chlorothalonil Residues in Cucumber and Cabbage Samples

Omer

Fakhre

2019

Journal of Spectroscopy

View full text Add to dashboard Cite

In this study, three simple and accurate spectrophotometric methods for simultaneous determination of pyriproxyfen and chlorothalonil residues in cucumbers and cabbages grown in experimental greenhouse were studied. e first method was based on the zero-crossing technique measurement for first and second derivative spectrophotometry. e second method was based on the first derivative of the ratio spectra. However, the third method was based on mean centering of ratio spectra. ese procedures lack any previous separation steps. e calibration curves for three spectrophotometric methods are linear in the concentration range of 1-30 μg·mL − 1 and 0.5-7 μg·mL − 1 for pyriproxyfen and chlorothalonil successively. e recoveries ranged from 82.12-97.40% for pyriproxyfen and 81.51-97.04% for chlorothalonil with relative standard deviations less than 4.95% and 5.45% in all instances for pyriproxyfen and chlorothalonil, respectively. e results obtained from the proposed methods were compared statistically by using one-way ANOVA, and the results revealed there were no significant differences between ratio spectra and mean centering methods with the zero-crossing technique. e proposed methods are successfully applied for the simultaneous estimation of the residue of both pesticides in cucumber and cabbage samples.

show abstract

“…And parasitoid Aphytis melinus was reported . New methods with HPLC‐DAD, LC–MS/MS, and fluorescence spectroscopy were developed for the determination and validation of pyriproxyfen in water solutions and tomatoes …”

Section: Introductionmentioning

confidence: 99%

“…[25][26][27][28] New methods with HPLC-DAD, LC-MS/MS, and fluorescence spectroscopy were developed for the determination and validation of pyriproxyfen in water solutions and tomatoes. 29,30 As is known, more than 40% of pesticides used in China are chiral pesticides. 31 The chiral chemicals may have identical physicochemical properties, but different biological activity, toxicity, absorption, transfer, and metabolism present in the environment on account of the dramatically different interactions with enzymes, receptors, or other chiral molecules for the enantiomers.…”

Section: Introductionmentioning

confidence: 99%

Enantioselective dissipation of pyriproxyfen in soils and sand

2017

View full text Add to dashboard Cite

Under normal conditions, the environmental behaviors of pesticides are affected by complex environmental factors and the manner of administration together with constraints. In order to meet the actual needs, we imitated the experiment and found that the degradation rate of pyriproxyfen in soils rendered complex changes. Rac-pyriproxyfen was successfully chiral separated on an AZ-H column and the residue analysis method was in accord with the demand of pesticide analysis. The results indicated that pyriproxyfen dissipated at a faster rate in Heilongjiang soil and Hainan soil, while at a much slower speed in another three soils and sand. Obvious enantioselective degradation was observed in Hainan soil and Qingdao sand. The results suggested that pyriproxyfen alone had low persistence in soil, but the moisture, soil type, the use of mixture formulation, and second spraying treatment could play important roles in dissipation of pyriproxyfen. Too large and too small moisture content could both make pyriproxyfen persist for a longer period in soil than in soil with 25% moisture content. Residues dissipated much slower after using Ai Qiu, while Shi Dingkang did not have a big effect on degradation, with only a small acceleration effect. Pyriproxyfen also dissipated in Hainan soil with difficulty after the second treatment.

show abstract

New HPLC and Fluorometric Methods for the Determination of Pyriproxyfen and Pyridalyl Insecticide Residues in Tomatoes

Cited by 8 publications

References 0 publications

Residue degradation, transfer and risk assessment of pyriproxyfen and its metabolites from tea garden to cup by ultra performance liquid chromatography tandem mass spectrometry

Residue degradation, transfer and risk assessment of pyriproxyfen and its metabolites from tea garden to cup by ultra performance liquid chromatography tandem mass spectrometry

Three Different Spectrophotometric Methods for Simultaneous Determination of Pyriproxyfen and Chlorothalonil Residues in Cucumber and Cabbage Samples

Enantioselective dissipation of pyriproxyfen in soils and sand

Contact Info

Product

Resources

About