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Development of ultrasound-assisted extraction followed by solid-phase extraction followed by dispersive liquid–liquid microextraction followed by gas chromatography for the sensitive determination of diazinon in garden parsley as vegetable samples

Rezaee Mohammad, Khalilian Faezeh, Pourjavid Mohammad Reza

Acta Chromatographica

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2023

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Vol. 35, no. 4

347--353

EN

A new pretreatment method termed ultrasound-assisted extraction (UAE) which is combined with solid-phase extraction which is combined with dispersive liquid-liquid microextraction (SPE-DLLME) followed by gas chromatography-flame ionization detector (GC-FID) analysis has been developed for the determination of diazinon in garden parsley as vegetable samples. The analyte was extracted from garden parsley sample using ultrasound-assisted extraction followed by solid-phase extraction followed by dispersive liquid-liquid microextraction. Various parameters that affect the efficiency of the extraction techniques have been optimized. The calibration plot was linear in the range of 5.0–1,000 μg kg⁻¹ with detection limit of 1.0 μg kg⁻¹ for diazinon in garden parsley samples. The results confirm the suitability of the UAE-SPE-DLLME-GC-FID as a sensitive method for the analysis of the targeted analyte in garden parsley samples.

2

Application of ultrasound-assisted deep eutectic solvent extraction combined with liquid-liquid extraction method to the extraction of three pesticide residues from fruit and vegetable samples

Chen Sue, An Qi, Sun Hong, Mao Mengqian

Acta Chromatographica

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2021

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Vol. 33, no. 1

30--36

EN

A simple, inexpensive and sensitive method was developed for the simultaneous determination of three pesticide residues (carbendazim, thiophanate-methyl, and imidacloprid) in fruit and vegetable samples using high performance liquid chromatography (HPLC) based on a combined pretreatment of ultrasoundassisted deep eutectic solvent extraction (UA-DES-E) and liquid-liquid extraction (LLE). In this study, various types of deep eutectic solvents (DESs) were synthesized and the extraction efficiency was compared as extraction solvents. Results showed that glycerol-proline 5 9:4 (GP-5) obtained the highest extraction efficiency among different types of DESs. Experiment conditions, including DES volume, extraction time and pH, were systematically optimized using single-factor experiment. Under the optimum conditions, the limits of detection (LODs) and quantification (LOQs) were in the ranges of 0.05– 0.2 mg$mL1 and 0.1–0.5 mg$mL1, respectively. The relative recoveries of the three pesticides in the fruit and vegetable samples ranged from 85.7 to 113.0% at two spiked levels. Meanwhile, the method achieved excellent linearity with determination coefficients (r) greater than 0.999. Furthermore, the method was successfully applied to the analysis of the pesticides in real fruit and vegetable samples (apple, tomato, and grape).

3

Qualitative analysis of the main polyphenols contained in apple pomace extract

Malinowska M., Śliwa K., Sikora E., Ogonowski J.

Czasopismo Techniczne. Chemia

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2016

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Y. 113, iss. 1-Ch

69--75

EN

The paper describes chosen methods for the extraction and qualitative analysis of the main polyphenolic compounds contained in apple pomace. Apple pomace is a by-product generated during apple juice production. The extracts were obtained with the Ultrasound Assisted Micelle Mediated Extraction (UAMME) method using a 1% Rocanol B2 water solution, as well as the Ultrasound Assisted Extraction (UAE) method in water. Thin Layer Chromatography (TLC) and UV/VIS spectroscopy were applied as analytical methods in order to identify the main polyphenolic substances in the obtained extracts. The obtained results showed that both UAMME as well as UAE are effective methods for obtaining quercetin, catechin and rutin.

PL

Artykuł opisuje wybrane metody pozyskiwania, a także analizę jakościową głównych związków polifenolowych zawartych w wytłokach z jabłek. Wytłoki jabłkowe stanowią produkt uboczny powstający podczas procesu produkcji soku jabłkowego. Ekstrakty uzyskano metodami ekstrakcji micelarnej wspomaganej ultradźwiękami w 1% wodnym roztworze Rokanolu B2 (UAMME) oraz ekstrakcji wspomaganej ultradźwiękami w wodzie (UAE). Do identyfikacji polifenoli w otrzymanych ekstraktach zastosowano metodę chromatografii cienkowarstwowej (TLC) oraz spektroskopię UV/VIS. Zarówno ekstrakcja micelarna wspomagana ultradźwiękami, jak i ekstrakcja w wodzie, wspomagana ultradźwiękami, okazały się skuteczne do pozyskiwania kwercetyny, katechiny oraz rutyny.

4

A study of the effects of cultivation variety, collection time, and climate on the amount of oleuropein in olive leaves

Hashemi P., Delfan B, Ghiasvand A. R., Alborzi M, Raeisi F

Acta Chromatographica

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2010

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Vol. 22, no. 1

133--140

EN

Effects of cultivation variety, collection time, and climate on amounts of oleuropein (OE), a strong antioxidant, in olive leaves were studied. A modified ultrasound-assisted method was used for efficient and quantitative extraction of OE from olive leaf samples before their analysis by a rapid HPLC method. Under the optimized conditions, the extraction was performed in two successive steps with an RSD better than 2.95% ( n = 5) and a detection limit of 0.02 μg OE. The amount of OE was determined in twelve samples of olive leaves from Mary Zeitoon, Koroneiki , and Sevillana varieties cultivated in three different regions of Iran after collection in two different seasons. The results confirmed that the amounts of OE varied in different olive varieties with mean values of 127, 115, and 144 μg g -1, respectively, although statistical tests indicated a significant interaction of collection time and climate with olive variety. In general, the OE concentration was significantly higher in the cold season and in the tropical regions than in the hot season and the temperate region.

5

Ultrasound-assisted acetic acid extraction of metals from soils

Krasnodębska-Ostręga B., Kowalska J.

Chemia Analityczna

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2003

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Vol. 48, No. 6

967-974

EN

In order to assess metal availability from soils to ecosystem the 16-h single extraction with 0.43 mol L(-1) CH(3)COOH (BCR) is being commonly applied. To shorten the extraction time of Cd, Pb and Zn from soil samples sonication has been'additionally applied. The influence of sonication time and temperature on the extraction efficiency has been studied. One compared the results obtained in both extraction procedures: ultrasonic and conventional BCR. The contents of Cd, Pb and Zn in soil extracts were determined by stripping voltammetry on hanging mercury drop electrode. ICP MS was used as a reference technique.

PL

16-godzinna ekstrakcja za pomocąO,43 mol L(-1) roztworu CH(3)COOH (procedura BCR) jest powszechnie wykorzystywana do określania dostępności metali z gleb do ekosystemu. W celu skrócenia czasu ekstrakcji Cd, Pb i Zn z gleb zastosowano ekstrakcję wspomaganą ultradźwiękami. Zoptymalizowano czas sonifikacji i temperaturę ekstrakcji. Porównano wydajności ekstrakcji wspomaganej ultradźwiękami z ekstrakcją przeprowadzoną według procedury BCR. Do oznaczeń zawartości Cd, Pb i Zn w ekstraktach zastosowano woltamperometrię ze wstępnym zatężaniem na wiszącej kroplowej elektrodzie rtęciowej oraz ICP-MS jako metodę porównawczą.

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Applicability of ultrasonic leaching by diluted acids for determination of total metal contents in plant materials

Borkowska-Burnecka J., Wisz J., Żyrnicki W.

Chemia Analityczna

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2003

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Vol. 48, No. 1

115-126

EN

Ultrasound assisted solid-liquid extraction as a plant sample preparation method preceding its multi-elemental analysis by ICP-OES was investigated. Various plant materials like: beet leaves, herb mixture and tobacco leaves (CTA-OTL-1, CTA-VTL-2) were studied. Diluted nitric and hydrochloric acids were employed as leaching solutions. The influence of temperature, time and the ratio of the sample mass to the acid volume on the efficiency of the leaching process were examined in order to determine the most appropriate extraction conditions. Concentrations of fifteen elements were measured by the ICP-OES method. The ultrasound-assisted extraction, performed at optimum conditions, was proved to be fast and quantitative method for the sample pretreatment before the determination of the total content of Ba, Ca, Cd, Cu, Mg, Mn, Ni, Pb, Sr and Zn. Al, Cr, Fe, Ti and V were found to be only partially extractable by dilute acids.

PL

W prezentowanej pracy badano ekstrakcję w układzie ciało stałe-ciecz wspomaganą ultradźwiękami, jako metodę przygotowania próbek roślinnych do analizy wielopierwiast-kowej za pomocą optycznej spektrometrii emisyjnej ze wzbudzeniem w indukcyjnie sprzężonej plazmie (ICP-OES). Do fugowania metali stosowano rozcieńczony kwas azotowy i solny. Ekstrakcji poddano różne materiały roślinne: liście buraka, mieszankę ziół oraz liście tytoniu (CTA-OTL-1 i CTA-VTL-2). Analizowano wpływ temperatury i czasu ekstrakcji oraz stosunku masy próbki do objętości ekstrahenta na efektywność przechodzenia pierwiastków do roztworu. Metodą ICP-OES mierzono stężenia 15 pierwiastków. Stwierdzono, że ekstrakcja wspomagana ultradźwiękami, przeprowadzona w optymalnych warunkach, jest szybką i ilościową metodą przygotowania próbek do jednoczesnego oznaczenia całkowitych zawartości Ba, Ca, Cd, Cu, Mg, Mn, Ni, Pb, Sr, i Zn w materiałach roślinnych. Zastosowanie rozcieńczonych kwasów pozwala jednakże tylko na częściowe wyługowanie takich pierwiastków jak Al, Cr, Fe, Ti i V.