Solriamfetol is a novel FDA approved enantiopure drug used for the treatment of excessive sleepiness associated with narcolepsy or obstructive sleep apnea. Only the active R-enantiomer is marketed, therefore, a method to determine the chiral purity is essential. Chiral separation of solriamfetol was performed by HPLC using polysaccharide-type chiral stationary phases in polar organic mode and described

Drugs of abuse can be investigated in dried blood spot (DBS) samples to evaluate the intake of psychoactive drugs. We have developed the validated liquid chromatography–tandem mass spectrometry method to determine drug of abuse in whole blood with DBS. The mass spectrometer was performed using multiple reaction monitoring via positive electro-spray ionization. The analysis procedure was applied to

Histamine level determination in fish and fish products is important for human safety, fish quality and food industry. For this reason, a rapid, robust, and precise method is needed. To achieve this objective, an HPLC method with fluorescence detection was developed and validated. Histamine in fish samples was efficiently extracted with perchloric acid, and purified with ion-exchange solid-phase extraction

Abstract Xiebai San (XBS) is a classical herbal prescription which has been used for the treatment of infantile cough and asthma for several hundred years. In this study, 39 compounds in XBS standard decoction were identified by HPLC–ESI–TOF system. Network pharmacology strategy was adopted to explore the relationship of chemicals, target genes and pathways, mulberroside A, kukoamine B and glycyrrhizic

In this study, a triazine-based polymeric network-modified magnetic nanoparticles (TPN/MNPs) was synthesized and applied as adsorbent for extraction of 1-naphthylacetic acid (NAA) from the fruit and vegetable samples followed by HPLC determination. The synthesized TPN/MNPs were characterized by the vibrating sample magnetometry (VSM), Fourier-transform infrared spectroscopy (FT-IR), field emission-scanning

A rapid reversed-phase gradient method employing a 50 mm × 1 mm i.d., C18 microbore column, combined with ion mobility and high-resolution mass spectrometry, was applied to the metabolic phenotyping of urine samples obtained from rats receiving different diets. This method was directly compared to a “conventional” method employing a 150 × 2.1 mm i.d. column packed with the same C18 bonded phase using

A high-performance liquid chromatographic method was developed for the separation and determination of 13 vitamin B compounds, including thiamin, riboflavin, riboflavin 5′-monophosphate, pyridoxine, hydroxocobalamin, cyanocobalamin, adenosylcobalamin, methylcobalamin, niacin, niacinamide, pantothenic acid, folic acid, and biotin. The method consisted of an ODS column, a gradient elution using pH 3

An analytical method based on solid-phase extraction–hydrophilic interaction chromatography–tandem mass spectrometry (SPE–HILIC–MS/MS) has been developed to quantify moniliformin in vegetable oil. The sample was extracted by methanol and purified by an Oasis MAX solid-phase extraction column. Following purification, it was separated by a Waters HILIC hydrophilic interaction column. Acetonitrile and

Abstract Amino acids are valuable nutrients, responsible for a variety of tasks in the human body. A favourable amino acid profile in gluten-free crops, such as millet, can thus be beneficial for human health, which is why 35 proso millet (Panicum miliaceum L.) samples, comprising 23 whole and 12 dehulled, were investigated regarding their amino acid profiles and compositions using acidic hydrolysis

Abstract As a potential DNA damaging substance, genotoxic impurities have been concerned by regulatory authorities in various countries. Two genotoxic impurities were found in imatinib mesylate which was a classical small molecule inhibitor of tyrosine kinase, and the analysis method has never been reported. A LC–MS/MS method was developed for the analysis of two genotoxic impurity materials: N-(5

The effects of the side chain and polymer backbone on the retention mechanisms of four polysaccharide-based sorbents, namely amylose 3,5-dimethylphenylcarbamate (Chiralpak IA), cellulose 3,5-dimethylphenylcarbamate (Chiralpak IB), amylose 3,5-dichlorophenylcarbamate (Chiralpak IE), and cellulose 3,5-dichlorophenylcarbamate (Chiralpak IC), were investigated using simple achiral molecules with distinct

A new selective reverse-phase high-performance liquid chromatography method with an attitude of practical use in pharmaceutical laboratories for simultaneous determination of Ascorbic acid, Acetaminophen, phenylephrine, Caffeine, Pamabrom, Guaifenesin, Dextromethorphan, Pyrilamine, Chlorpheniramine maleate, Ibuprofen in the presence of Methyl, Ethyl, Butyl Parabens as preservatives has been developed

Abstract A three-phase hollow fiber liquid-phase microextraction based on reversed micellar supramolecule was developed and employed for the determination of quality markers of three anthraquinones in Rhubarb and their plasma protein binding rates. Moreover, the extraction mechanism of reversed micellar supramolecule and determination mechanism of plasma protein binding rate by the proposed method

We introduced a new molecular imprinted polymers (MIPs) monolithic column of Mycophenolate mofetil (MMF) for HPLC. The monolithic column was prepared using MMF as the template molecule, methcrylic acid (MAA) as the functional monomer, vinyl ester resin as the crosslinking agent and AIBN as the initiator. HPLC was used to study the binding and separation performance of MIPs for template MMF and its

Microfluidic paper-based analytical devices (µPADs) take the paper as a base material and integrate nanoscale microchannel on it for multiple detections. Its unique properties like low cost, portability, simple operation, and easy to save make it better than the traditional microfluidic chips. While designed originally for point-of-care medical diagnostics, µPADs have attracted the attention of many

Abstract A convenient method based on microwave-assisted hydrothermal extraction coupled to ion chromatography was proposed for comprehensive analysis of chemical composition in biological samples. Water was used as extraction solvent and a small amount of alkali or a small volume of acid was served as modifier to improve extraction efficiency. Factors affecting extraction efficiency were investigated

An ion chromatography (IC) method coupled with solid-phase extraction was established for the simultaneous determination of trace organic acids and inorganic anions in sodium carboxymethyl cellulose (CMC). To prevent CMC from contaminating analytical column, a self-packed solid-phase extraction column packed with quaternized adsorbents was applied in sample pretreatment. An IonPac, AS11-HC column was

Recurrent respiratory tract infections (RRTIs) is one of the most common diseases in children and adolescents, especially for preschool children. Tongkang tablet (TKT), a traditional Chinese medical formula consisting of Astragali Radix (AR), Atractylodes Macrocephala (AM), Saposhnikovia Divaricata (SD), Rhizoma Dioscoreae (RD), Concha Ostreae (CO), and Pericarpium Citri Reticulatae (PCR), has been

Trimellitic anhydride (TMAn) is an essential starting material of the chemical manufacturing industry; it is widely used in saturated polyester resins (SPR) manufacturing to produce plasticizers for different purposes. TMAn was recently added, as a new substance of very high concern, to the candidate list by the European Chemicals Agency, since it can lead to sensitization, respiratory tract irritation

A new consumable-free three-dimensional comprehensive gas chromatography (GC3-FID) was designed with modulators already known to comprehensive two-dimensional gas chromatography (GC × GC) users to showcase the opportunity of implementing GC3 systems. A hybrid interface composed of a thermal desorption modulator and a fast forward-flush differential flow modulator was used with modulation periods of

Porous organic cages (POCs) are an emerging class of porous molecular materials which self-assembled by discrete, shape-persistent, cage-like molecules and have recently received intensive interest in diverse fields. In this work, a hydroxyl-functionalized homochiral POC was synthesized by [4 + 6] condensation of 2-hydroxy-1,3,5-triformylbenzene with (1R, 2R)-diaminocyclohexane and coated on a capillary

Biogenic amines (BAs) are important compounds that can be used in the quality control of food and beverages. BA analysis is a challenging task that can be made easier by applying a derivatizing agent like dansyl chloride (DNS). The optimized capillary zone electrophoresis (CZE) separation of the DNS-BA derivates (derivates of cadaverine, histamine, putrescine, tryptamine, and tyramine) was performed

A new chromatographic stationary phase was prepared by making a soft organic monolith based on thermal polymerization of methyl methacrylate and ethylene glycol di-methacrylate with an aid of gas evolution via decomposition of urea, and by crushing the monolith into particles. The original purpose of urea incorporation was formation of monolith particles with affluent mesopores, but the actual effect

In view of the US pharmacopeia (USP)-proposed general chapter \(\left\langle {1220} \right\rangle\) “The Analytical Procedure Lifecycle” and ICH-proposed ICHQ14 guideline “Analytical Procedure Development”, application of quality by design approach during analytical method development gains a significant importance. Methods developed by QbD approach will be more robust and thereby decrease efforts

Parenterally administered snake antivenom immunoglobulins are the only specific treatment for envenoming by snakebites. Endotoxin removal is a necessary part of good manufacturing practice for antivenom products to avoid life-threatening consequences associated with injecting endotoxin-contaminated product. Optimization of pH is an essential factor in endotoxin purification. This study aimed to compare

In the original publication, the phrase “Liquid phase” in Table 1 column 1 was included in the wrong line. The phrase needs to be included in row 13 in front of LPME.

A sensitive and reliable method using liquid chromatography–negative electrospray ionization mass spectrometry was developed for the simultaneous determination of chloramphenicol, florfenicol, and thiamphenicol at trace levels in animal feed. The analytes were extracted from grinded feed with ethyl acetate. Further the ethyl acetate was evaporated, residue resuspended in Milli-Q water, defatted with

The thermodynamic surface and interfacial properties of some hydrocarbons used as process oils in rubber industry were determined using the inverse gas chromatography technique at infinite dilution. In this paper, four different common process oils, such as distillated aromatic extract, treated distillate aromatic extract, mildly extracted solvate, and hydro-processed naphthenic oil, were studied.

Sample preparation is a critical step in the separation of target analytes from complex matrices, which can influence the reliability and accuracy of the resulting analysis. Recent trends in sample preparation techniques are directed toward the automation and online coupling of sample preparation units, miniaturization, high efficiency, low costs, and reducing or eliminating solvent consumption. Microextraction

A simple but effective method was developed for the ultra-trace determination of two tropane alkaloid residues, hyoscyamine and scopolamine, in honey. Honey samples were dissolved in a concentrated aqueous solution of sodium acetate from which the alkaloids were subsequently extracted using acetonitrile. The resulting extract was analyzed using HILIC–ESI-MS/MS without any additional extract cleanup

Eggs are one of the most common foods in the world, and their safety is a major concern for the public. We aimed to develop a novel clean-up approach named Bond Elut Enhanced Matrix Removal-Lipid (EMR-Lipid) for the simultaneous determination of 325 pesticides in the chicken egg by UHPLC–MS/MS and GC–MS/MS. The initial step of extraction was adopted by acetonitrile with 5% formic acid and subsequent

Abstract A selective method of high performance liquid chromateography-quadrupole/time of flight-tandem mass spectrometry is described for the characterization of related substances in bacitracin samples. The chromatographic separation of the components of bacitracin was carried out using a Diamonsil Plus C18 column, a mixture of ammonium formate buffer (50 mM, pH 4.0) and acetonitrile was used as

A capillary electrophoresis (CE) method was developed for the screening of 5′-methylthioadenosine nucleosidase (MTAN) inhibitors in traditional Chinese drugs and small molecular compounds. In this method, reaction occurred at the capillary inlet during a predetermined waiting period, followed by electrophoretic separation of the reaction substrates and products. Parameters affecting separation efficiency

This research introduces a novel solid-phase microextraction technology, in which the features of heating of sample, cooling of sorbent, and extraction under vacuum condition have been merged. Heating-, cooling- and vacuum-assisted solid-phase microextraction (HCV-SPME) method was developed as an efficient solution for the direct extraction of volatile and semi-volatiles species in complex solid samples

An effective method for the determination of 20 free amino acids in tea samples using 4-(carbazole-9-yl)-benzyl chloroformate (CBBC-Cl) as a derivatization reagent by high-performance liquid chromatography combined with fluorescence detection (HPLC-FLD) has been established. CBBC-Cl quickly derivatized amino acids within 6 min in basic solution (pH 9.0) at room temperature (ca. 25 °C). The maximum

A sensitive method was developed and validated for the determination of UV filters (oxybenzone, octocrylene, 4-methyl-benzylidene camphor, 2-ethylhexyl-4-methoxycinnamate and avobenzone) in tilapia muscle using matrix solid-phase dispersion followed by on-line solid-phase extraction–liquid chromatography/UV. The validation showed good linearity from 100 to 3600 ng g−1 with r2 values > 0.98. Precision

A polyacrylonitrile (PAN) coating was fabricated by electrospinning technique for using as a new extraction phase in mechanical stir bar sorptive extraction (MSBSE). The setup coupled with gas chromatography (GC) was proposed and applied for the extraction and determination of some low molecular weight polycyclic aromatic hydrocarbons (PAHs) in water samples. The effective parameters on the extraction

A new automated flow-through adsorption/desorption procedure using a multiwalled carbon nanotube immobilised mixed matrix membrane is described. The membrane consisted of 25% (w/w) multiwall carbon nanotube loading in a cellulose triacetate polymer matrix as support and was cast and embedded in a flow-through cell with a channel of an approximate length of 20 mm, a width of 2 mm, and a depth of 1.5 mm

Abstract An accurate assay suitable for human biomonitoring of multiclass antibiotics preferred for veterinary use is currently lacking. In this study, we developed a liquid chromatography-triple quadrupole tandem mass spectrometry (LC–QqQ–MS/MS) method for analysis of 41 representative antibiotics (eight categories) and their two metabolites in human urine samples. Additionally, along with matrix-matched

Abstract Fifteen structurally different 4C-substituted pyrrolidin-2-one derivatives were used as model analytes for investigation of enantioseparation abilities on six commercially available polysaccharide-based coated chiral stationary phases (cellulose tris (3,5-dimethylphenylcarbamate), cellulose tris (3-chloro-4-methylphenylcarbamate), cellulose tris (4-methylbenzoate), cellulose tris (4-chlor

Abstract A simple derivatization reaction with N,N-dimethylformamide dimethyl acetal (DMF-DMA) was developed for the analysis of perfluorocarboxylic acids (PFCA, C4–C12) in solid samples by gas chromatography–mass spectrometry (GC–MS). After extraction with methyl tert-butyl ether (MTBE), the samples are mixed with derivatizing agent and injected into GC. The derivatization reaction takes place in

Abstract A method for the simultaneous determination of glyphosate and aminomethylphosphonic acid (AMPA) in urine was developed using a “dilute-and-shoot” sample preparation. A 1:1 dilution of urine sample in 15 mmol L−1 heptafluorobutyric acid (HFBA) was prepared prior to being injected into the LC–MS/MS system. The chromatographic separation was achieved by a Gemini C6-Phenyl analytical column, with

Abstract Polyhedral oligomeric silsesquioxanes (POSSs) are a class of important hybrid inorganic/organic materials. When POSSs are used as the building block in polymerization, the materials show superior performance over their organic counterparts in many areas due to the special Si–O cage structure. However, the stereoisomers (cis, trans) of polyhedral oligomeric silsesquioxane (POSS) show some differences

Abstract Room-temperature ionic liquids (RTILs) have proven to be efficient polar or highly polar stationary phases for GC. Nevertheless, the thermal stability of monocationic RTILs limits their use in high-temperature GC. To improve the thermal stability, an RTIL based on a 1-methylimidazolium derivative was anchored in a three-dimensional network using the sol–gel process. Three different strategies

Abstract Hawthorn leaves, officially listed in the 2015 Chinese Pharmacopoeia, comes from Crataegus pinnatifida Bge. var. major N. E. Br. and Crataegus pinnatifida Bge. It has the effect of invigorating blood and dissolving stasis, regulating qi and dredging veins, turbid, and lipid-lowering. This work was designed to explore the spectrum–effect relationship between high-performance liquid chromatography

Abstract Zidebactam (ZID) is a novel drug in clinical development; it potentiates the antibacterial activity of β-lactam antibiotics. Two reversed phase liquid chromatographic (RP-LC) methods were developed for ZID; a mass spectrometer (MS) compatible method for identification and another UV detection method for the quantification of impurities. Four impurities and three degradation products (DPs)

Abstract The methionine cycle is a key pathway to provide substrates for many basic biological processes including methylation and redox reactions. Here, we demonstrated a rapid and sensitive liquid chromatography–tandem mass spectrometry (LC–MS/MS) method for quantifying the metabolites and co-factors of the methionine metabolism. The analytes included methionine, S-adenosylmethionine, S-adenosylhomocysteine

Abstract In the present study, carbon nanodots (CNDs) were successfully anchored on magnetite (Fe3O4) under magnetic stirring and the nanocomposite prepared was assessed as a new adsorbent for ultrasonic-assisted magnetic solid-phase dispersive extraction of chlorpyrifos (CPF) and triclosan (TCS) in water samples. Detection was achieved using ultrahigh performance liquid chromatography–tandem mass

Abstract The traditional optimization of extraction for sample pre-treatment usually involves only the single-factor experimental design to obtain the best conditions of performance. However, in optimization, only employing the single-factor experimental design becomes less frequent as it ignores the interaction among various factors. To identify the effective or critical factors and interactions among

Abstract The misuse of so called novel psychoactive substances is still a challenging problem worldwide. A special attribute of a lot of these compounds is a chiral centre enabling two possible enantiomers probably related to different pharmacological and toxicological properties. The goal of the present study was to present a simple and isocratic HPLC–UV method for enantioseparation of mainly cathinone

Abstract The reversed-phase ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry method was developed during the study and successfully applied to separation and analysis of unmodified and antisense oligonucleotides. It was shown that oligonucleotide separation strongly depends on the stationary phase type. The type, pH and salt content in the mobile phase influence

Abstract The present investigation reports the synthesis of graphene oxide–polyvinyl poly pyrrolidone composite and its application in the extraction of aflatoxins in food samples. This composite was successfully synthesized and characterized with analytical instruments such as UV–Vis, FITR, XRD, and SEM techniques. The extraction was carried out by reinforced hollow fiber liquid-phase microextraction

Abstract A wealth of physico-chemical information has been obtained on an insoluble and crystalline polypyrrole/titanium oxide (PPY/TiO2) using the Inverse Gas Chromatography Method (IGC). Twenty-five solvents (test compounds) with different specific interactions were used. PPY/TiO2 was synthesized and characterized by FTIR and DSC methods. The following characteristics of PPY/TiO2 were explored: changes

The retention behavior of polyethylene glycol (PEG) on different types of hydrophobic interaction chromatography (HIC) resins containing butyl, octyl, and phenyl ligands was analyzed. An incomplete elution or splitting of the polymer peak into two parts was observed, where the first one was eluted at the dead time of the column, whereas the second one was strongly retained. The phenomenon was attributed

Abstract Meso- and macroporous spherical silica gels of pore sizes in the range of 60-1000 Å and 40-75 µm particle size were investigated as a stationary phase for the separation and purification of polysaccharides and poly(ethylene glycols) (PEGs) of various MWs using an aqueous mobile phase. Sephadex and Bio-Gel were used for comparison as the most common stationary phases for similar purposes. The

Asymmetrical flow field-flow fractionation (AF4) and hollow-fiber flow field-flow fractionation (HF5) are techniques widely used in analytical, industrial and biological analyses. The main problem in all AF4 and HF5 analyses is sample loss due to analyte-membrane interactions. In this work the impact of liquid carrier composition on latex nanoparticles (NPs) separation in water and two different concentrations

Dihydralazine and hydrochlorothiazide were stored at high temperature and humidity, under UV/Vis light and different pH, as individual drugs and the mixture. Then, a sensitive and selective HPLC-UV method was developed for simultaneous determination of dihydralazine and hydrochlorothiazide in presence of their degradation products. Finally, the degradation products were characterized through LC-DAD

Abstract Nitric oxide (NO) is a small molecule involved in the regulation of many physiological processes. It plays a crucial role in the regulation of nervous system, immune and inflammatory responses, and blood flow. NO is synthesized by nitric oxide synthase (NOS) during two-step oxidation of l-arginine to l-citrulline. Intermediates and derivatives of NO metabolism, such as l-arginine, l-citrulline

Baby food has never been the object of biogenic amine profiling. The aim of this study was to develop a highly sensitive method for analysis of biogenic amines in ready-to-eat baby foods. The principle of the developed method involves high-performance liquid chromatography coupled to single-quadrupole mass spectrometry (HPLC-APCI-MS) of dansyl derivatives, presented also in comparison with common diode

The overreaching purpose of this study is to evaluate new approaches for determining the optimal operational and column conditions in chromatography laboratories, i.e., how best to select a packing material of proper particle size and how to determine the proper length of the column bed after selecting particle size. As model compounds, we chose two chiral drugs for preparative separation: omeprazole