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Micellar Liquid Chromatography

Dina S Shokry, Laura J Waters, Gareth M B Parkes, John C Mitchell
Micellar liquid chromatography (MLC) is a popular method used in the determination of a compounds lipophilicity. This study describes the use of the obtained micelle/water partition coefficient (log Pmw ) by such a method in the prediction of human intestinal absorption (HIA). As a result of the close resemblance of the novel composition of the micellar mobile phase to that of physiological intestinal fluid, prediction was deemed to be highly successful. The unique micellar mobile phase consisted of a mixed micellar mixture of lecithin and six bile salts, i...
July 30, 2018: Biomedical Chromatography: BMC
Isabel Cristina Celerino de Moraes Porto, Dayse Chaves Cardoso de Almeida, Gabriela Vasconcelos Calheiros de Oliveira Costa, Tayná Stéphanie Sampaio Donato, Letícia Moreira Nunes, Ticiano Gomes do Nascimento, José Marcos Dos Santos Oliveira, Carolina Batista da Silva, Natanael Barbosa Dos Santos, Maria Luísa de Alencar E Silva Leite, Irinaldo Diniz Basílio-Júnior, Camila Braga Dornelas, Pierre Barnabé Escodro, Eduardo Jorge da Silva Fonseca, Regianne Umeko Kamiya
BACKGROUND: Propolis is a natural substance produced by bees and is known to have antimicrobial activity. Our aim was to evaluate the antimicrobial effect of micellar nanocomposites loaded with an ethyl acetate extract of Brazilian red propolis as a cavity cleaning agent and its influence on the color and microtensile bond strength (μTBS) of the dentin/resin interface. METHODS: An ultra-performance liquid chromatography coupled with a diode array detector (UPLC-DAD) assay was used to determine the flavonoids and isoflavones present in an ethyl acetate extract of Brazilian red propolis (EARP) and micellar nanocomposites loaded with EARP (MNRP)...
July 18, 2018: BMC Complementary and Alternative Medicine
Fawzia Ibrahim, Asmaa Kamal El-Deen, Kuniyoshi Shimizu
In the present study, we compare the performance of two reversed-phase liquid chromatographic approaches using different eluents either conventional hydro-organic eluent or micellar one for simultaneous estimation of hydrocortisone acetate and pramoxine hydrochloride in presence of their degradants and process-related impurities; hydrocortisone and 4-butoxyphenol, respectively. For conventional reversed-phase liquid chromatography (RPLC), separation of the studied compounds was completed on an Inertsil ODS 3-C18 column (150 mm × 4...
July 2018: Journal of Food and Drug Analysis
Sarah Nasser, Paulo De Sa Peixoto, Anne Moreau, Thomas Croguennec, Fabrice Bray, Christian Rolando, Frederic J Tessier, Alain Hedoux, Guillaume Delaplace
During storage, a series of changes occurs for dairy powders such as protein lactosylation, formation of Maillard reaction products (MRP) leading to powder browning and increase of insoluble matter. The kinetics of protein lactosylation and MRP formation are influenced by lactose content of the dairy powder. However, influence of lactose in the formation of insoluble matter and its role in the underlying mechanisms is still a subject of speculation. In this study, we aim to investigate the role of lactose in the formation of insoluble matter in a more comprehensive way than the existing literature...
June 29, 2018: Journal of Agricultural and Food Chemistry
Ester Peris-García, Jorge Rodríguez-Martínez, Juan J Baeza-Baeza, María Celia García-Alvarez-Coque, María José Ruiz-Angel
Most reports in reversed-phase liquid chromatography (RPLC) with micellar mobile phases make use of the anionic sodium dodecyl sulfate. This surfactant masks efficiently the silanol groups that are the origin of the poor efficiencies and tailing peaks observed for basic compounds in conventional RPLC. However, it has the handicap of yielding excessive retention, which forces the addition of an organic solvent to reduce the retention times to practical values. Other surfactants, such as the non-ionic polyoxyethylene(23)lauryl ether (Brij-35), are rarely used...
June 19, 2018: Analytical and Bioanalytical Chemistry
Jessica Fiori, Benedetta Pasquini, Claudia Caprini, Serena Orlandini, Sandra Furlanetto, Roberto Gotti
Monomeric catechins are important compounds in green tea accounting for potential bioactivity against a wide range of diseases. Besides catechins, l-Theanine (γ-glutamylethylamide), a characteristic amino acid in tea leaves, has become a further focus of the phytochemical research for the reported beneficial effects mainly on cognitive performance, emotional state and sleep quality. In the present study has been developed a CD-MEKC method based on sodium dodecyl sulfate (SDS) and Heptakis (2,6-di-O-methyl)-β-cyclodextrin for the separation of six major green tea catechins and enantiomers of theanine...
August 10, 2018: Journal of Chromatography. A
F Belal, F Ibrahim, Z A Sheribah, H Alaa
A method based on micellar liquid chromatography to quantify levodopa, carbidopa and entacapone in plasma is reported. The sample pretreatment was a simple dilution in a pure micellar solution then filtration and direct injection, without requiring extraction or purification steps. The three drugs were resolved from the matrix in 7 min, using an aqueous solution of 0.1 M sodium dodecyl sulphate-10% n-propanol-0.3 tiethylamine, adjusted at pH 2.8 with 0.02 M orthophosphoric acid as mobile phase, running under isocratic mode at 1...
August 1, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Samereh Ranjbar Bandforuzi, Mohammad Reza Hadjmohammadi
The extraction of phthalate esters (PEs) from aqueous matrices using two-phase solvent bar microextraction by organic micellar phase was investigated. A short hollow fiber immobilized with reverse micelles of Brij 35 surfactant in 1-octanol was served as the solvent bar for microextraction. Experimental results show that the extraction efficiency were much higher using two-phase solvent bar microextraction based on non-ionic surfactant than conventional two-phase solvent bar microextraction because of a positive effect of surfactant-containing extraction phase in promoting the partition process by non-ionic intermolecular forces such as polar and hydrophobicity interactions...
August 3, 2018: Journal of Chromatography. A
Qing Yang, Beibei Chen, Man He, Bin Hu
A rapid, simple, and effective method has been developed for the determination of seven triazine herbicides (terbutryn, prometryn, ametryn, prometon, propazine, atrazine, simazine) by coupling off-line hollow fiber liquid liquid liquid microextraction (HF-LLLME) with on-line sweeping micellar electrokinetic chromatography (sweeping-MEKC). In HF-LLLME, seven target triazines in hydrophobic form were extracted from the sample solution into decane impregnated in the pores of the hollow fiber, and then back-extracted into 1 mol L-1 H3 PO4 inside the hollow fiber lumen...
August 15, 2018: Talanta
Natalia Miękus, Ilona Olędzka, Natalia Kossakowska, Alina Plenis, Piotr Kowalski, Adam Prahl, Tomasz Bączek
Nowadays, ionic liquids (ILs) are receiving more attention in various fields of analytical chemistry. Their contribution to the enhancement of the clean-up, extraction, separation and determination of trace amounts of various biologically important compounds in distinct matrices is well documented. Moreover, their importance as "green chemistry" solvents has been pointed out. Advanced analytical methods based on the IL-assisted microextraction and electrophoretic determination of minute concentrations of neurotransmitters (NTs) in samples are presented here for the first time...
August 15, 2018: Talanta
Moussa Yabré, Ludivine Ferey, Issa Touridomon Somé, Karen Gaudin
The greening of analytical methods has gained increasing interest in the field of pharmaceutical analysis to reduce environmental impacts and improve the health safety of analysts. Reversed-phase high-performance liquid chromatography (RP-HPLC) is the most widely used analytical technique involved in pharmaceutical drug development and manufacturing, such as the quality control of bulk drugs and pharmaceutical formulations, as well as the analysis of drugs in biological samples. However, RP-HPLC methods commonly use large amounts of organic solvents and generate high quantities of waste to be disposed, leading to some issues in terms of ecological impact and operator safety...
May 2, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Danielle Cristina da Silva, Cláudio Celestino Oliveira
Method for extraction and determination of amoxicillin, caffeine, ciprofloxacin, norfloxacin, tetracycline, diclofenac, ibuprofen, nimesulide, levonorgestrel, and 17 α -ethynylestradiol exploiting micellar liquid chromatography with PDA detector and solid-phase extraction was proposed. The usage of toxic solvents was low; the chromatographic separation of the medicaments was performed using a C18 column and mobile phases A and B containing 15.0% (v/v) ethanol, 3.0% (m/v) sodium dodecyl sulfate (SDS), and 0...
2018: Journal of Analytical Methods in Chemistry
Mehdi Moini
In the past few years, there has been a significant effort by the forensic science community to develop new scientific techniques for the analysis of forensic evidence. Forensic chemists have been spearheaded to develop information-rich confirmatory technologies and techniques and apply them to a broad array of forensic challenges. The purpose of these confirmatory techniques is to provide alternatives to presumptive techniques that rely on data such as color changes, pattern matching, or retention time alone, which are prone to more false positives...
May 2018: Electrophoresis
Brandon Carter, Hasmukh Patel, David M Barbano, MaryAnne Drake
Traditionally most protein ingredients are sold as a powder due to transport ease and longer shelf life. Many high-protein powder ingredients such as milk protein concentrate with 85% protein and micellar casein concentrate have poor rehydration properties (e.g., solubility) after storage, which might limit their use. An alternative to the production of dried protein ingredients is the option to use liquid protein ingredients, which saves the cost of spray drying, but may also improve flavor and offer different functional properties...
May 2018: Journal of Dairy Science
Susann Schröder, Barbara Wenzel, Winnie Deuther-Conrad, Rodrigo Teodoro, Mathias Kranz, Matthias Scheunemann, Ute Egerland, Norbert Höfgen, Detlef Briel, Jörg Steinbach, Peter Brust
Specific radioligands for in vivo visualization and quantification of cyclic nucleotide phosphodiesterase 2A (PDE2A) by positron emission tomography (PET) are increasingly gaining interest in brain research. Herein we describe the synthesis, the 18 F-labelling as well as the biological evaluation of our latest PDE2A (radio-)ligand 9-(5-Butoxy-2-fluorophenyl)-2-(2-([18 F])fluoroethoxy)-7-methylimidazo[5,1- c ]pyrido[2,3- e ][1,2,4]triazine (([18 F]) TA5 ). It is the most potent PDE2A ligand out of our series of imidazopyridotriazine-based derivatives so far (IC50 hPDE2A = 3...
March 2, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Ying Chen, Kunze Du, Jin Li, Yun Bai, Mingrui An, Zhijing Tan, Yan-Xu Chang
A simple cloud point preconcentration method was developed and validated for the determination of gallic acid, bergenin, quercitrin, and embelin in Ardisia japonica by high-performance liquid chromatography (HPLC) using ultrasonic assisted micellar extraction. Nonionic surfactant Genapol X-080 was selected as the extraction solvent. The effects of various experimental conditions such as the type and concentration of surfactant and salt, temperature, and solution pH on the extraction of these components were studied to optimize the conditions of Ardisia japonica ...
2018: International Journal of Analytical Chemistry
Reem N El Gammal, Mohammed E A Hammouda, Dalia R El-Wasseef, Saadia M El-Ashry
A simple rapid and accurate micellar high performance liquid chromatographic method was improved and validated for the analysis of mixture containing gatifloxacin sesquihydrate (GTF) and prednisolone acetate (PRED) in their synthetic mixture and their combined preparation. The separation was achieved using a C18 column, micellar mobile phase consisted of 0.2 M sodium dodecyl sulfate, 12.5% n-propanol and 0.3% triethylamine in 0.02 M orthophosphoric acid at pH 7.0 at a flow rate of 1 ml/min with UV detection at 270 nm...
April 1, 2018: Journal of Chromatographic Science
Idaira Pacheco-Fernández, Verónica Pino, Jacob Lorenzo-Morales, Juan H Ayala, Ana M Afonso
A novel ionic liquid (IL)-based microextraction method has been developed for the determination of four hydroxylated polycyclic aromatic hydrocarbons (OHPAHs) in urine samples. The water soluble IL-based surfactant selected as extraction solvent is decylguanidinium chloride (C10 Gu-Cl), the cytotoxicity and micellar behavior of which were evaluated. The proposed salt-induced IL-based preconcentration method simply consists in adding NaClO4 to the aqueous medium containing the IL to promote its water insolubility...
July 2018: Analytical and Bioanalytical Chemistry
Amir M Ramezani, Ghodratollah Absalan, Raheleh Ahmadi
Bilayer pseudo-stationary phase micellar liquid chromatography (MLC) was developed for simultaneous isocratic isolation of hydrochlorothiazide, as a basic-polar (hydrophilic) cardiovascular drug, as well as triamterene and losartan potassium, as acidic-nonpolar (hydrophobic) cardiovascular drugs. Utilizing a deep eutectic solvent (DES), as a novel green mobile phase additive in combination with acetonitrile (ACN) and acetic acid (ACA), drastically improved the chromatographic behavior of the drugs. Concentration of sodium dodecyl sulphate (SDS), as well as volume percentages of ACN, DES, and ACA were optimized by using a central composite design...
June 20, 2018: Analytica Chimica Acta
Marat I Kamalov, Trinh Đặng, Natalia V Petrova, Alexander V Laikov, Duong Luong, Rezeda A Akhmadishina, Andrei N Lukashkin, Timur I Abdullin
A new self-assembled formulation of methylprednisolone succinate (MPS) based on a carboxylated trifunctional block copolymer of ethylene oxide and propylene oxide (TBC-COOH) was developed. TBC-COOH and MPS associated spontaneously at increased concentrations in aqueous solutions to form almost monodisperse mixed micelles (TBC-COOH/MPS) with a hydrodynamic diameter of 19.6 nm, zeta potential of -27.8 mV and optimal weight ratio ∼1:6.3. Conditions for the effective formation of TBC-COOH/MPS were elucidated by comparing copolymers and glucocorticoids with different structure...
April 1, 2018: Colloids and Surfaces. B, Biointerfaces
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