Journal of Separation Science

In this work, surface molecularly imprinted polymers based on magnetic multi-walled carbon nanotubes were prepared for the specific recognition and adsorption of resveratrol. The functionalization of magnetic multi-walled carbon nanotubes and the synthesis process of surface molecularly imprinted polymers were optimized. Characterizations were performed to demonstrate the successful synthesis of the imprinted materials. The imprinted materials showed satisfactory adsorption capacity of resveratrol (45.73 ± 1...

In this work, the potential synergetic effect between deep eutectic solvents and an antibiotic chiral selector (clindamycin phosphate) for enantioseparation was investigated in capillary electrophoresis. We synthesized a series of deep eutectic solvents with choline chloride as hydrogen bond acceptor and three α-hydroxyl acids (l-lactic acid, l-malic acid, and l-tartaric acid) as hydrogen bond donors. Compared to the single clindamycin phosphate separation system, significantly improved separations of model drugs were observed in several synergetic systems...

Generic electromembrane extraction (EME) methods were developed and optimized for basic analytes of moderate or low polarity, employing prototype conductive vial EME equipment. Two generic methods, B1 and B2, were devised for mono- and dibasic compounds with distinct polarity windows: 2.0 < log P < 6.0 for B1 and 1.0 < log P < 4.5 for B2. In B1, 10 μL of 2-nitrophenyl octyl ether served as the liquid membrane, while B2 utilized 10 μL of 2-undecanone...

Reasonable design and construction of functionalized materials are of great importance for the enrichment of global phosphopeptides. In this work, Ti4+ functionalized hydrophilic covalent organic frameworks by introducing glutathione (GSH) and 2,3,4-trihydroxy benzaldehyde (THBA) via click chemistry and Schiff base reaction (COF-V@GSH-THBA-Ti4+ ) was constructed and applied for selective enrichment of phosphopeptides in serum. Benefit from the high surface area, excellent hydrophilicity as well as regular mesoporous structure, COF-V@GSH-THBA-Ti4+ displayed high selectivity (molar ratio of 2000:1), low limit of detection (0...

Although filtration is one of the most common steps in sample preparation for chemical analysis, filter membrane materials can leach contaminants and/or retain some analytes in the filtered solutions. In multiclass, multiresidue analysis of veterinary drugs, it is challenging to find one type of filter membrane that does not retain at least some of the analytes before injection in ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). In this study, different filter membranes were tested for use in UHPLC-MS/MS analysis of 183 diverse drugs in bovine muscle, kidney, and liver tissues...

Zanthoxylum, as a medicinal and edible herbal medicine, has a long history and complex chemical composition. There are many varieties of Zanthoxylum, and there are differences in composition between varieties. In this study, a rapid classification and identification method for the main components of Zanthoxylum was established using ultra-high-performance-liquid chromatography quadrupole-orbitrap-mass spectrometry. The components of Shandong Zanthoxylum bungeanum, Wudu Zanthoxylum bungeanum, and Zanthoxylum schinifolium were identified by studying the characteristic fragmentations and neutral losses of characteristic components...

Countercurrent chromatography (CCC) is a potent separation approach known for its remarkable efficiency and capacity in preparation. It's applied as a substitute or combined with different chromatographic techniques, resulting in its rebranding as multidimensional CCC (MDCCC). Numerous essential mixtures from natural products contain hundreds or thousands of distinct components of importance. These mix types are too complicated to separate in any reasonable time using a single CCC dimension. However, if a multidimensional technique is utilized, where a complex mixture is separated by an initial dimension, smaller fractions of that separation are gathered...

Understanding and comparing the applicability of electromembrane extraction (EME) and liquid-phase microextraction (LPME) is crucial for selecting an appropriate microextraction approach. In this work, EME and LPME based on supported liquid membranes were compared using biological samples, including whole blood, urine, saliva, and liver tissue. After optimization, efficient EME and LPME of clozapine from four biological samples were achieved. EME provided higher recovery and faster mass transfer for blood and liver tissue than LPME...

In the present study, twelve compounds from Dioscorea spongiosa were successfully purified by an efficient technique combined bioassay-guided fractionation macroporous resin column chromatography (MRCC) pretreatment and high-speed counter-current chromatography (HSCCC) separation for the first time. Then, D101 MRCC was used to fractionate the crude extract into five parts, which further applied the bioassay-guided fractionation strategy to screen the active fractions of 2 and 4. As for the separation, 200 mg Fr...

Glutamine is the most abundant free proteinogenic α-amino acid. It is naturally produced in the organism and acts as a precursor for the synthesis of different biologically important molecules (such as proteins or nucleotides). However, under stressful conditions, the organism is unable to produce it in enough amounts to function properly. Thus, glutamine (Gln)-based supplements have become increasingly popular over the last decade. Since legal regulations establish that amino acid-based dietary supplements must contain only the L-enantiomer and not the racemate, adequate chiral methodologies are required to achieve their quality control...

Qiangli Dingxuan (QLDX) tablet is a widely recognized traditional Chinese medicine formula that has been extensively used in China for decades to treat vertigo, tinnitus, and dizziness owing to its outstanding therapeutic outcomes. However, the complexity of the chemical components in this tablet makes it challenging to separate and identify these components. This study presented an effective and sensitive strategy for the rapid separation and simultaneous structural identification of QLDX tablet components using ultra-performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry and the UNIFI platform...

Charged aerosol detection, increasingly recognized for quantifying pharmaceutical compounds with weak ultraviolet absorption, is a universal detection technique for high-performance liquid chromatography (HPLC). Charged aerosol detection shows a non-linear response with increasing analyte concentration over a wide range, limiting its versatility in various analytical applications. In this work, a co-optimization strategy for power function value (PFV) and power laws was proposed and applied to broaden the linear range of the standard curve of saccharides in Qishen Yiqi dripping pills using the HPLC-charged aerosol detection (HPLC-CAD) method...

WenDanTang (WDT) is a Chinese herbal formula used to treat various diseases, including neurodegenerative diseases. However, the neuroprotective metabolic pathways and the components involved in this process are not fully understood. In this study, we examined the neuroprotective metabolic pathways of WDT in rat brains using cerebrospinal fluid metabolomics and ultra-high-performance liquid chromatography-high-resolution mass spectrometry. Twelve rats were randomly divided into a WDT (administrated with WDT solution) and a control group...

Designing advanced stationary phases to improve separation efficiency is essential in capillary electrochromatography. Due to their outstanding performance, covalent organic frameworks have recently demonstrated considerable promise in the field of separation science. Herein, an open-tubular capillary electrochromatography method was reported using porous imine-based covalent organic framework with sufficiently available interaction sites as stationary phase. The imine-based covalent organic framework coated capillary was easily prepared via an in situ growth method at room temperature, and its separation performance was evaluated, indicating the high separation efficiency for three types of analytes, including herbicides, polybrominated dibenzofurans, and bisphenols...

A new green micellar liquid chromatographic method has been developed and validated for the simultaneous determination of diphenhydramine (DPH) and tripelennamine hydrochloride (TRP) using a micellar mobile phase consisting of 1 mM Tween 20 in phosphate buffer pH 4:isopropanol (85:15, %v/v). The method was linear in the range of 4-150 and 5-120 μg/mL for TRP and DPH, respectively. The method was successfully applied for the simultaneous determination of DPH and TRP in a laboratory-prepared gel containing all possible excipients with mean percent recoveries ± standard deviation of 100...

Polyethylene glycol (PEG) is one of the most commonly used polymers in drug delivery systems. The investigation of the pharmacokinetic behavior of PEG is important for revealing the toxicity and efficiency of PEG-related Nano-drug delivery systems. A high through-put and selective ultra-high-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) method coupled with collision-induced dissociation (CID) in source technique was developed and validated to determine PEG1K polymers in cellular samples in this study...

In this study, three commercially available low-density polyethylene (LDPE) polymers produced via a tubular reactor process, with varying melt flow rates at 190°C/2.16 kg (4.0, 1.9, and 0.75 g/10 min), have been selected and subjected to high temperature-size exclusion chromatography (SEC) analysis coupled with an infrared-5 (IR-5), viscometer (VISCO), and multiangle laser light-scattering detectors. The molecular weight (MW), MW distribution, short-chain branching (SCB), and long-chain branching parameters were investigated...

In this study, we developed physically adsorbed multi-layer coatings using poly-l-lysine or poly(diallyldimethylammonium chloride) and gold nanoparticles, which were functionalized with bovine serum albumin for the chiral separation in electrochromatography. The approach involves sequentially depositing positively charged polymers and negatively charged citrate-stabilized gold nanoparticles. By repeating this modification cycle, we created two- and four-layer coatings, which were sequentially functionalized with albumin forming three- and five-layer coatings that were finally applied for the separation of enantiomers of dl-tryptophan...

Fufang Xiling Jiedu capsule (FXJC), a traditional Chinese medicine that evolved from "Yinqiao Powder", is widely used for the treatment of cold and influenza. However, due to a lack of in vivo metabolism research, the chemical components responsible for the therapeutic effects still remain unclear. Hence, this study aimed to describe the metabolic profiles of the FXJC in rat plasma, urine, and feces. A combined data mining strategy based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry was employed and 201 xenobiotics, including 117 prototype components and 84 metabolites were detected...

The comprehensive and efficient characterization of components in traditional Chinese medicine is crucial for elucidating its active constituents and uncovering its mechanism. Identifying the compounds of the Bushen Huoxue Prescription (BHP) is difficult because of its complex composition and the large difference in concentration among its compounds. In this study, a hydrophilic interaction liquid chromatography coupled with reversed-phase LC (HILIC × RPLC) offline 2D-LC tandem high-resolution mass spectrometry method was established to analyze the total compounds of the BHP...