No‐additive salting‐out liquid–liquid extraction—A tool for purification of positively charged compounds from highly salted reaction mixtures

Synthetic antioxidants play a critical role in the storage and process of edible oils due to that they can retard lipid oxidation, maintain the quality of oils, and prolong the shelf life. However, a series of studies have proved the potential risks of synthetic antioxidants for human health when consumed in excess, and many countries have established the permitted amounts of synthetic antioxidants in oils. Thus, the accurate quantification of synthetic antioxidants in edible oils is necessary, and there have developed various analytical methods involved in chromatographical, electrochemical, and spectroscopic methods. Owing to the complex matrix and the incompatibility between the oil sample and the detection instrument, sample preparation is usually adopted prior to the instrument detection to improve the detection effectiveness. The current review aims to provide a comprehensive overview of the recently developed sample preparation methods and analytical techniques applied to determine synthetic antioxidants in edible oils from 2010 to present, with emphasis on the sample preparation methods combined with separation-based analytical techniques such as capillary electrophoresis and liquid chromatography with various detectors. The advantages and limitations of some typical analytical methods are discussed and some insights in the future perspectives are also provided in this review.

Section: Sample Preparation Methodsmentioning

confidence: 99%

Current sample preparation methods and analytical techniques for the determination of synthetic antioxidants in edible oils

Wang

Liu

et al. 2022

“…to form a homogeneous phase with the sample followed by phase separation [9][10][11]. This special mode of LLE is known as homogeneous liquidliquid extraction (HLLE) and it shows superior performance due to the formation of a homogenous phase, which increases the accessibility of the extractant to the analyte [12]. Furthermore, the water-miscible solvents used in HLLE are in general safer and more eco-friendly, which makes HLLE a greener approach of sample preparation [13,14].…”

Section: Introductionmentioning

confidence: 99%

Homogeneous liquid–liquid extraction as an alternative sample preparation technique for biomedical analysis

Hammad

Abdallah

Bedair

et al. 2021

Liquid-liquid extraction is a widely used technique of sample preparation in biomedical analysis. In spite of the high pre-concentration capacities of liquidliquid extraction, it suffers from a number of limitations including time and effort consumption, large organic solvent utilization, and poor performance in highly polar analytes. Homogeneous liquid-liquid extraction is an alternative sample preparation technique that overcomes some drawbacks of conventional liquid-liquid extraction, and allows employing greener organic solvents in sample treatment. In homogeneous liquid-liquid extraction, a homogeneous phase is formed between the aqueous sample and the water-miscible extractant, followed by chemically or physically induced phase separation. To form the homogeneous phase, aqueous samples are mixed with water-miscible organic solvents, waterimmiscible solvents/cosolvents, surfactants, or smart polymers. Then, phase separation is induced chemically (adding salt, sugar, or buffer) or physically (changing temperature or pH). This mode is rapid, sustainable, and cost-effective in comparison with other sample preparation techniques. Moreover, homogeneous liquid-liquid extraction is more suitable for the extraction of delicate macromolecules such as enzymes, hormones, and proteins and it is more compatible with liquid chromatography with tandem mass spectrometry, which is a vital technique in metabolomics and proteomics. In this review, the principle, types, applications, automation, and technical aspects of homogeneous liquid-liquid extraction are discussed.

“…LLE is one of the most common methods for sample preparation in which a large volume of a water immiscible organic solvent (e.g., chloroform, ether, or ethyl acetate) are mixed with the sample, separated, evaporated, and finally reconstituted in the smallest possible amount of a suitable solvent [1–4]. In spite of the wide acceptability of LLE as a sample preparation technique for biological fluids, it is labor‐intensive, time consuming, and nonecofriendly.…”

Section: Introductionmentioning

confidence: 99%

“…LLE is one of the most common methods for sample preparation in which a large volume of a water immiscible Article Related Abbreviations: EF, enrichment factor; ICH, International Conference of Harmonization; IS, internal standard; LLME, liquid-liquid microextraction; LPME, liquid phase microextraction; SALLME, salting-out induced liquid-liquid microextraction; SULLME, sugaring-out induced liquid-liquid microextraction organic solvent (e.g., chloroform, ether, or ethyl acetate) are mixed with the sample, separated, evaporated, and finally reconstituted in the smallest possible amount of a suitable solvent [1][2][3][4]. In spite of the wide acceptability of LLE as a sample preparation technique for biological fluids, it is labor-intensive, time consuming, and nonecofriendly.…”

Section: Introductionmentioning

confidence: 99%

Sugaring‐out induced homogeneous liquid‐liquid microextraction as an alternative mode for biological sample preparation: A comparative study

Abdallah

Hammad

Bedair

et al. 2021

Miniaturization of liquid‐liquid extraction is a growing field of sample preparation to reduce solvent consumption, protect the environment, and preserve operators’ health. In this work, four different modes of liquid‐liquid microextraction have been compared including dispersive liquid‐liquid microextraction, binary and ternary salting‐out, and sugaring‐out induced liquid‐liquid microextraction. The extraction efficiency was evaluated by the enrichment factors of 14 different drugs from three pharmacological classes. Compared with the other modes, sugaring‐out induced liquid‐liquid microextraction was found to be the most efficient and, thus, it was applied for sample preparation of the antivirals in human plasma. Method optimization was performed using response surface methodology for the sugar type and amount (in mg), the sample pH, the equilibration time (in min), and the extractant volume (in µL). The method was then validated and found linear in the concentration range of 0.10‐10 µg/mL for daclatasvir, 0.05‐10 µg/mL for velpatasvir, and 0.20‐10 µg/mL for ledipasvir, with correlation coefficients in the range 0.996‐0.999. These results shows that sugaring‐out induced liquid‐liquid microextraction could be a more efficient microextraction mode for preparation of biological samples. Compared with other types of microextraction, sugaring‐out induced liquid‐liquid microextraction is greener, simpler, and cost‐effective, with less tendency to affect the sample pH.