Journal of Separation Science

Fri, 11/20/2020 - 22:09
Polyethyleneimine‐modified magnetic multi‐walled carbon nanotubes were developed to extract 10 mycotoxins. Simple modification of polyethyleneimine was achieved on the magnetic substrate by using an epoxy‐containing silane agent as a linker. The resultant magnetic adsorbent was integrated with reverse phase and anion exchange interaction sites. Under optimal extraction conditions, only 20.0 mg...
Wed, 11/18/2020 - 22:08
The advent of a new pharmaceutical formulation evokes the need for examining the chemical stability of their constituents and establishing proper stability‐indicating methods. Herein, the stability of the newly co‐formulated Tamsulosin and Tadalafil were examined under different stress conditions. The acidic degradation of Tamsulosin yielded its sulfonated derivative, while Tadalafil was...
Tue, 11/17/2020 - 22:09
The aim of this study was to establish and validate an alternative high‐performance liquid chromatography (HPLC) method for simultaneous quantification of pyrazinamide, isoniazid, acetyl‐isoniazid and rifampicin in plasma of patients under treatment for tuberculosis. The performed method was lineal (r2>0.99) in the range of 2.00‐50.00 μg/mL for pyrazinamide, 0.50‐20.00 μg/mL for both acetyl‐...
Tue, 11/17/2020 - 22:09
A novel worm‐like nickel‐titanium oxide nanocomposites coating was directly grown on a nickel‐titanium alloy wire by low‐voltage electrochemical anodization in alkaline ethylene glycol and water solution. The in situ growth of nickel‐titanium oxide nanocomposites greatly depended on the volume ratio of ethylene glycol to water and temperature. Coupled to HPLC with UV detection by static...
Fri, 11/13/2020 - 22:10
Food can contain unwanted compounds and need to be analyzed for compounds like carcinogenic polycyclic aromatic hydrocarbons to ensure consumer safety. The analytes need to be extracted from the sample matrix and cleaned‐up to enable detection. However, established methods for clean‐up are labor‐intensive and have a high expenditure on organic solvents. Here we show a newly developed micro solid‐...
Thu, 11/05/2020 - 22:11
A solid phase extraction method combined with deep eutectic solvent‐based dispersive liquid‐liquid microextraction has been developed for the extraction of three antibiotics in honey samples prior to their determination by ion mobility spectrometry. In this method, firstly, a multi‐wall carbon nanotube/urea‐formaldehyde nanocomposite was synthesized using co‐precipitation polymerization method...
Tue, 10/27/2020 - 22:12
An open tubular capillary column (100 μm internal diameter and 120 cm length) was first fabricated with N‐phenylacrylamide and styrene copolymer layer on the inner surface by in situ one‐pot strategy, while ethylene dimethacrylate was used as the cross‐linker. The pretreated silica‐fused capillary was reacted with 3‐trimethoxysilyl propyl methacrylate to attach a double bond ligand onto the inner...
Fri, 10/02/2020 - 22:10
Bisphenol A is a synthetic compound widely used in industry, in the production of polycarbonate, epoxy resins and thermal paper, among others. Its annual production is estimated at millions of tons per year, demonstrating its importance. Despite its wide application in various everyday products, once in the environment (due to its disposal or leaching), it has high toxicity to humans and animal...
Fri, 10/02/2020 - 22:10
With metabolism being one of the main routes of drug elimination from the body (accounting for removal of around 75% of known drugs), it is crucial to understand and study metabolic stability of drug candidates. Metabolically unstable compounds are uncomfortable to administer (requiring repetitive dosage during therapy), while overly‐stable drugs increase risk of adverse drug reactions....
Thu, 10/01/2020 - 22:11
This work reports an HPLC method development able to simultaneously determine perampanel and stiripentol, two third‐generation antiepileptics whose therapeutic spectrum can potentially be extended, in several mouse matrices. A salting‐out assisted liquid‐liquid extraction optimized by a design of experiments approach was adopted for samples preparation. Isopropanol and magnesium sulfate were the...
Sun, 09/27/2020 - 22:13
A facile method was introduced for preparing a biocharcoal aerogel, which was derived from pomelo peel as the only raw material. The inner spongy layer of pomelo peel was freeze‐dried for maintaining three‐dimensional structure, further carbonized under high temperature and oxygen‐limited conditions. The morphological structure and graphitization degree of biocharcoal aerogel were characterized...
Fri, 09/11/2020 - 22:11
Priority pollutants chlorophenols are broadly used chemicals that are persistent in the environment and causing serious human health hazards. The current study introduces a novel adsorbent for the extraction of chlorophenols from river water, surface water, and milk by headspace solid phase microextraction coupled with GC. The adsorbent composite was prepared by blending polycaprolactam (nylon‐6...
Thu, 09/10/2020 - 22:11
Variation in inter‐human attractiveness to mosquitoes, and the preference of mosquitoes to bite certain regions on the human host, are possible avenues for identifying lead compounds as potential mosquito attractants or repellents. We report a practical, non‐invasive method for the separation and detection of skin surface chemical compounds and comparison of skin chemical profiles between the...
Thu, 09/10/2020 - 22:11
In the last years, multidimensional liquid chromatography technique became very widespread for the complete separation of non‐volatile analytes in complex matrices. The main advantage of these techniques, especially when coupled with mass spectrometry, is the enhancement of separation power or peak capacity, due to an increase in selectivity and sensitivity of the two systems. With respect to...
Mon, 08/31/2020 - 22:11
An accurate and sensitive ultra‐high‐performance liquid chromatography coupled with triple quadrupole mass spectrometry method was established and validated for the determination of 9 bioactive compounds of Ligustri Lucidi Fructus in rat plasma. Separation was performed on Halo® C18 column with a mobile phase of acetonitrile and 0.1% formic acid in water. The eluate was detected by multiple‐...
Mon, 08/24/2020 - 21:28
A simple, fast, and sensitive analytical protocol using fabric‐phase sorptive extraction followed by high performance liquid chromatography with ultraviolet detection has been developed and validated for the extraction of five parabens including methylparaben, ethylparaben, propylparaben, butylparaben, and benzylparaben. In the present work, sol‐gel polyethylene glycol coated fabric‐phase...
Sat, 08/15/2020 - 22:12
Polycyclic aromatic hydrocarbons, ubiquitous compounds which result from incomplete combustion or pyrolysis of natural and man‐made combustion sources, can adversely affects human health due to their well‐known toxicity. This paper demonstrates the significant potential of graphene/chitosan composite aerogels as solid‐phase extraction sorbents for efficient polycyclic aromatic hydrocarbon...
Tue, 08/11/2020 - 22:11
A new analytical method based on capillary LC with diode array detection has been developed for the simultaneous quantification of seven neonicotinoid insecticides commercially available (imidacloprid, thiacloprid, clothianidin, thiamethoxam, acetamiprid, nitenpyram and dinotefuran) in honey samples. The separation was achieved in a Zorbax XDB‐C18 column (150 × 0.5 mm id, 5 μm), with a mobile...
Tue, 08/04/2020 - 22:10
This study ascertained the viability of a portable liquid chromatograph, operating at low μL/min flow, for the analysis of seized drugs at remote sites as well as in laboratory settings. Synthetic cathinones were screened using dual capillary columns in series, C8 and biphenyl, with on‐column ultraviolet detection at 255 nm and 275 nm. The relative retention times of the two columns in series and...
Thu, 07/30/2020 - 22:10
In this work, graphene oxide‐hybridized high internal emulsion polymers with crosslinking and open‐cell structure was prepared and applied for separation and enrichment of estrogens. The prepared graphene oxide‐hybridized high internal emulsion polymer monoliths had hydrophobicity, porosity and stability, which were just obtained by one step in‐situ emulsion polymerization of 2‐ethylhexyl...
Thu, 07/30/2020 - 22:10
A method for separation and determination of 32 fentanyl‐related substances, including seven sets of isomeric fentanyl analogues, was developed using ultra‐high‐performance liquid chromatography coupled with quadrupole‐orbitrap high‐resolution mass spectrometry. The collision energy, chromatographic column and mobile phase were optimized. All compounds were efficiently flushed out of a universal...
Thu, 07/30/2020 - 22:10
An analytical method for the determination of 6 emerging derivatives or metabolites together with 25 common macrolides antibiotics in milk by ultra‐performance liquid chromatography quadrupole/electrostaticfield orbitrap mass spectrometry was established. The samples were purified with optimized Quick, Easy, Cheap, Effective, Rugged, Safe methods. The amounts of primary‐secondary amine, C18 and...
Wed, 07/29/2020 - 22:09
Peptide sequencing is critical to the quality control of peptide drugs and functional studies of active peptides. A combination of peptidase digestion and mass spectrometry technology is common for peptide sequencing. However, such methods often cannot obtain the complete sequence of a peptide due to insufficient amino acid sequence information. Here, we developed a method of generating full...
Fri, 07/24/2020 - 22:10
A magnetic covalent organic framework material was synthesized with a core‐shell structure using a simple solvothermal method. It was prepared with Fe3O4 as the magnetic core, covalent organic framework as the shell, which synthesized from 1,3,5‐triformylphloroglucinol and p‐phenylenediamine by Schiff base reaction. The transmission electron microscope, Fourier transform infrared spectroscopy,...
Thu, 07/23/2020 - 22:10
A sample pretreatment method based on the combination of a three‐phase solvent extraction system and deep eutectic solvent‐based dispersive liquid–liquid microextraction has been introduced for the extraction of four organochlorine pesticides in cocoa samples before their determination by gas chromatography–electron capture detection. A mixture of sodium chloride, acetonitrile, and potassium...
Tue, 07/21/2020 - 22:09
Although an efficient and stable fiber coating is essential for the development of solid‐phase microextraction technique, it remains a challenging prospect. Herein, an inorganic nanocomposite material Ag2S@ZnS was prepared and used as a coating for fibers to detect polycyclic aromatic hydrocarbons in water samples in combination with a GC with flame ionization detector. Compared with a single ZnS...
Tue, 07/14/2020 - 22:11
In order to enhance the extraction performance, a mesoporous silica was modified with ordered mesoporous carbon for solid‐phase microextraction. Three stainless steel wires coated with the mesoporous material were placed in a polyetheretherketone tube for getting an extraction tube. The tube was coupled to high performance liquid chromatography with diode array detector, and the online analysis...
Fri, 07/10/2020 - 22:10
Levetiracetam is an antiepileptic drug for the treatment of psychiatric patients. In this study, a selective, straightforward, and rapid online heart‐cutting LC method was developed for the therapeutic drug monitoring of levetiracetam. This method allows for the determination of levetiracetam in human plasma without complex sample preparation. The mobile phases consisted of 30 mM aq. ortho‐...
Fri, 07/10/2020 - 22:10
Drug resistance is one of the main problems of cancer treatment. For this reason, combination therapy is commonly used for years. The combination of a chemotherapeutic, carboplatin, and the epigenetic drug decitabine is a new approach to modulate drug resistance. Nanoparticulate systems can overcome the drawbacks associated with the drug combinations. An analytical method that can detect and...
Tue, 07/07/2020 - 22:09
Emerging drugs usually mimic the effects of traditional drugs, but are not always controlled due to the chemically altered structures. Positional isomers of emerging drugs are challenging to analyze because they challenge the separation and detection techniques commonly employed by forensic laboratories. The utility of silica hydride (SiH) stationary phases for the ultra high performance liquid...
Mon, 07/06/2020 - 22:10
This research is an application of fiber‐in‐tube solid phase microextraction followed by HPLC‐UV for extraction and determination of trace amounts of bisphenol A. Nano magnetic Fe3O4 was formed on the surface of polypropylene porous hollow fibers to increase the surface area and then it was coated with polystyrene. The introduction of polystyrene improves the surface hydrophobicity and is an...
Mon, 07/06/2020 - 22:10
CE is a modern separation technique characterized by many benefits, which qualify it also for enzyme assays and the study of enzyme kinetics during drug development. Homogenous or heterogenous approaches can be followed for the enzymatic incubation. In this study, an immobilization procedure of aldehyde oxidase on magnetic particles was developed considering their integration with CE. A number of...
Fri, 07/03/2020 - 22:10
Detecting pesticide residues in human serum is a challenging process. This study developed and validated a method for the extraction and recovery of residues of multiple classes of pesticides from serum using one reagent. Salt‐assisted acetonitrile extraction and HPLC with quadrupole time of flight MS/MS were used to quantitate 34 pesticides classified in nine groups of chemicals in human serum...
Fri, 07/03/2020 - 22:10
The study aimed to establish a automated versatile sample preconcentration method based on the modified immunomagnetic beads, which was utilized to enrich for aflatoxin B1 from the matrices. The critical main parameters affecting the extraction efficiency, such as usage amount of immunomagnetic beads, reaction time, elution time, blending way was investigated. Under the optimized conditions, the...
Wed, 06/24/2020 - 22:09
Bilobetin, a natural compound extracted from Ginkgo biloba, has various pharmacological activities such as anti‐oxidation, anti‐cancer, anti‐bacterial, anti‐fungal, anti‐inflammatory, anti‐viral, and promoting osteoblast differentiation. However, few studies have been conducted and there are no reports on its metabolites owing to its low content in nature. In addition, it has been reported to...
Wed, 06/17/2020 - 22:10
A novel, facile, and robust strategy was proposed to increase the pore size and mechanical strength of cryogels. By mixing the monomers of acrylamide and 2‐hydroxyethyl methacrylate as the precursor, a monolithic copolymer cryogel with large interconnected pores and thick pore walls was prepared. Hydrogen bonding between the two monomers contributed to the entanglement and aggregation of the...
Mon, 06/15/2020 - 22:09
Roukou Wuwei pills is one of the most commonly used Mongolian medicinal prescriptions and historically used for the treatment of depression. This research aimed to illustrate the metabolic characteristic of Roukou Wuwei pills in vivo. To address this objective, an ultra high performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry method based metabonomics approach was...
Wed, 06/10/2020 - 22:11
In this work, a simple, fast, sensitive, and environmentally friendly method was developed for preconcentration and quantitative measurement of bisphenol A in water samples using GC‐MS instrument. The preconcentration approach, namely biosorption‐based dispersive liquid‐liquid microextraction with extractant removal by magnetic nanoparticles was performed based on the formation of microdroplet of...
Sun, 06/07/2020 - 22:10
A fast, green, sensitive, and accurate analytical method using HPLC couple with fluorescence detection, was established and validated for the simultaneous determination of amlodipine besylate and celecoxib in their recently approved fixed‐dose combination tablets (1:20). Separation of the two drugs was achieved on C18 reversed phase column (Thermo ODS Hypersil,4.6 × 250 mm, particle size 5μm)...
Sun, 06/07/2020 - 22:10
A mesoporous silica was functionalized by carbon nanotubes to enhance the extraction performance. The mesoporous material was coated on stainless steel wires, and three wires were inserted inside of a polyetheretherketone tube for in‐tube solid‐phase microextraction. The tube was coupled to high performance liquid chromatography with diode array detection to obtain online analytical system, then...
Sat, 05/30/2020 - 03:30
Graphene oxide has received extensive attention because of its unique properties and potential applications. In this study, magnetic nitrogen‐doped graphene was prepared by one‐step hydrothermal reaction using urea as the dopant and reductant, and ferroferric oxide nanoparticles were in‐situ deposited on the surface of the nanohybrids. The magnetic nitrogen‐doped graphene was characterized using...
Sun, 05/17/2020 - 03:25
In this work, various types of metal‐organic frameworks were synthesized, and their affinities towards buprenorphine were evaluated using dispersive solid‐phase extraction. The extracted buprenorphine was determined by ultra‐performance liquid chromatography‐ultraviolet detection system. The highest extraction recovery was observed by employing zeolitic imidazole framework‐67. Then, a facile and...
Mon, 05/11/2020 - 03:27
A new sol‐gel hybrid methyltrimethoxysilane‐chloropropyltriethoxysilane was prepared as sorbent for solid phase extraction. The extraction efficiency of the prepared sol‐gel hybrid methyltrimethoxysilane‐chloropropyltriethoxysilane were assessed by using three selected organophosphorus pesticides namely chlorpyrifos, profenofos and malathion. Gas chromatography‐mass spectrometry was used for...
Fri, 04/24/2020 - 03:24
In this study, the new and efficient three‐dimensional network porous aromatic frameworks materials called as Silica‐PAFs‐a, Florisil‐PAFs‐a, Silica‐PAFs‐b and Florisil‐PAFs‐b were first synthesized. The properties of materials were analyzed by five characterization methods. And they were used as adsorbents in pipette‐tip solid‐phase extraction for the effective determination of carbendazim and...
Mon, 04/13/2020 - 03:18
A novel solid‐phase microextraction fiber was synthesized by coating of stainless steel wire with polyoxomolybdate368/polyaniline as a sorbent aimed at extraction of amitriptyline, nortriptyline and doxepin as antidepressant drugs from urine and blood samples. The polyoxomolybdate368/polyaniline composite coating was carried out using electropolymerization process under constant potential. This...
Sun, 04/12/2020 - 03:18
Monitoring biological samples at trace levels of chemicals from anthropogenic actions such as pesticides, pharmaceuticals and hormones has become a very important subject. This work describes a method for the determination of 8 compounds of different chemical classes in human urine samples. Dispersive liquid‐liquid microextraction based on magnetic ionic liquids was used as the sample preparation...
Thu, 04/09/2020 - 03:20
Kang‐Ai injection, which is composed of Astragali Radix, Ginseng Radix, et Rhizoma, and kushenin, is extensively used in China as an adjuvant therapy for many types of cancer and chronic hepatitis B. In the present study, 47 herbal compounds (11 alkaloids, 8 astragalosides, and 28 ginsenosides), were detected in Kang‐Ai injection by ultra‐high‐performance liquid chromatography coupled to...
Mon, 04/06/2020 - 03:17
In the present work, a novel database of drug compounds and a rapid screening method based on ultra‐high performance liquid chromatography coupled to high resolution orbitrap mass spectrometry were developed and applied in the screening and identification of targeted and non‐targeted antihypertensive adulterants in dietary supplements and herbal medicines. The established screening database...
Fri, 04/03/2020 - 03:17
A solid phase microextraction with carbon nanospheres coated fiber coupled with gas chromatographic detection was established for the determination of eight polycyclic aromatic hydrocarbons (naphthalene, biphenyl, acenaphthene, fluorine, phenanthrene, anthracene, fluoranthene and pyrene) in water and soil samples. The experimental parameters (extraction temperature, extraction time, stirring rate...
Wed, 04/01/2020 - 03:17
Amphiphilic diblock copolymers consisting of a hydrophobic core containing a polymerized ionic liquid and an outer shell composed of poly(N‐isoprolylacrylamide) were investigated by CE and asymmetrical flow field flow fractionation. The polymerized ionic liquid comprised poly(2‐(1‐butylimidazolium‐3‐yl)ethyl methacrylate tetrafluoroborate) with a constant block length (n = 24), while the length...

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