References of "Fillet, Marianne"
     in
Bookmark and Share    
Peer Reviewed
See detailQuantitative profiling of endogenous polar metabolites from low volumes of blood samples
Kok, Miranda ULiege; Fillet, Marianne ULiege

Conference (2017, November 08)

The etiology of many diseases is not yet completely understood. The involved biological processes might be resolved using a metabolomics approach, because metabolomics provides unique challenging ... [more ▼]

The etiology of many diseases is not yet completely understood. The involved biological processes might be resolved using a metabolomics approach, because metabolomics provides unique challenging opportunities to correlate the metabolome with a physiological or pathophysiological status and provides a vision on the relationships between genes, gene expression, environment and lifestyle. Here, we present the development of two ultra-high performance liquid chromatography (UHPLC) methods coupled to mass spectrometry (MS) for the separation and quantitation of polar metabolites in blood samples. A reversed-phase UHPLC-MS/MS method has been developed to quantify anionic energetic metabolites, whereas hydrophilic interaction chromatography (HILIC)-MS/MS has been used to determine amino acids. Two sample pretreatment procedures have been developed for an optimal recovery of the respective metabolites from whole blood samples. One method involved the precipitation of proteins with organic solvents and acids. In addition, volumetric absorptive microsampling has been used for the sample preparation. Small and accurate quantities of biological fluids (10 or 20 µL) can be collected with this sampling technique, which is of great interest for volume-limited samples or serial collection of samples. The developed methods have been validated and will be applied to determine differences in metabolite concentrations between blood samples from patients and controls. This can lead to a breakthrough in the understanding of diseases and can open new therapeutic perspectives. [less ▲]

Detailed reference viewed: 23 (5 ULiège)
Peer Reviewed
See detailQuantitative profiling of endogenous polar metabolites from low volumes of blood samples
Kok, Miranda ULiege; Fillet, Marianne ULiege

Poster (2017, October 05)

The etiology of many diseases is not yet completely understood. The involved biological processes might be resolved using a metabolomics approach, because metabolomics provides unique challenging ... [more ▼]

The etiology of many diseases is not yet completely understood. The involved biological processes might be resolved using a metabolomics approach, because metabolomics provides unique challenging opportunities to correlate the metabolome with a physiological or pathophysiological status and provides a vision on the relationships between genes, gene expression, environment and lifestyle. Here, we present the development of two ultra-high performance liquid chromatography (UHPLC) methods coupled to mass spectrometry (MS) for the separation and quantitation of polar metabolites in blood samples. A reversed-phase UHPLC-MS/MS method has been developed to quantify anionic energetic metabolites, whereas hydrophilic interaction chromatography (HILIC)-MS/MS has been used to determine amino acids. Two sample pretreatment procedures have been developed for an optimal recovery of the respective metabolites from whole blood samples. One method involved the precipitation of proteins with acetonitrile and acids. In addition, volumetric absorptive microsampling has been used for the sample preparation. Small and accurate quantities of biological fluids (10 or 20 µL) can be collected with this sampling technique, which is of great interest for volume-limited samples or serial collection of samples. The developed methods have been validated and will be applied to determine differences in metabolite concentrations between plasma samples from patients and controls. This can lead to a breakthrough in the understanding of diseases and can open new therapeutic perspectives. [less ▲]

Detailed reference viewed: 17 (1 ULiège)
Peer Reviewed
See detailIdentification and quantitation of intact virus-like particles of human papillomavirus (HPV-VLP) using capillary electrophoresis
Bettonville, Virginie ULiege; Nicol, Jérôme; Furst, Tania et al

Conference (2017, September 19)

Detailed reference viewed: 38 (6 ULiège)
Full Text
See detailChallenges in the determination of amyloid oligomeric species by two electrophoretic techniques
Napp, Aurore ULiege; Houbart, Virginie ULiege; Demelenne, Alice ULiege et al

Poster (2017, September 18)

Parkinson’s disease is a frequent degenerative disorder, and for the moment the diagnosis is mainly clinical. When the first symptoms appear, loss of more than 70% of the dopaminergic cells already ... [more ▼]

Parkinson’s disease is a frequent degenerative disorder, and for the moment the diagnosis is mainly clinical. When the first symptoms appear, loss of more than 70% of the dopaminergic cells already occurred. Knowing that, it is of high interest to have one (or more) reliable biomarker(s) at our disposal to diagnose Parkinson before the first symptoms appear. Alpha-synuclein (aSyn) is a protein physiologically expressed at high level by neuronal cells, under a monomeric form. This protein would play a critical role in the development of the disease because under certain conditions, aSyn is capable of self-assembly to form fibrils like those found in Lewy bodies. Other intermediate soluble forms like dimers and oligomers are also formed. As these forms seems to be the toxic species, they are the center of many attentions. The quantification of each form would be a great help, but for the moment only the total forms (of monomeric or oligomeric) can be quantified. In this study, aSyn oligomers were generated after optimization of incubation conditions (pH, temperature, agitation, …). Then, different approaches were investigated to detect and follow the different species formed during the aggregation. We analyzed the oligomers by capillary gel electrophoresis (CGE) and SDS-PAGE. We found that capillary gel electrophoresis is a promising automated technique to analyze aSyn oligomers, due to the fact that it separates the aggregates according to their size, like the SDS-PAGE, but with more advantages. To gain sensitivity and selectivity by CGE, we used a laser-induced fluorescence detector. As aSyn do not have a native fluorescence, we derivatized it. After careful screening and optimization of various derivatization reagents, we could quantify with high sensitivity aSyn oligomers by CGE-LIF. We realized different calibration curves, and we had promising results that will allow us to quantify the different aSyn oligomeric forms in biological fluids. [less ▲]

Detailed reference viewed: 20 (1 ULiège)
Peer Reviewed
See detailSampling only 10 μL of whole blood to study the bioavailability of itraconazole formulations in rats
Kok, Miranda ULiege; Thiry, Justine ULiege; Evrard, Brigitte ULiege et al

Conference (2017, September 12)

Background Volumetric absorptive microsampling (VAMS) offers a unique opportunity to collect small and accurate quantities of biological fluids. This sampling technique is of great interest for volume ... [more ▼]

Background Volumetric absorptive microsampling (VAMS) offers a unique opportunity to collect small and accurate quantities of biological fluids. This sampling technique is of great interest for volume-limited samples and for the collection of multiple samples from the same animal. This serial sample collection may reduce the number of required study animals, thereby fulfilling the three Rs rule (refine, reduce, replace). Here, we demonstrate the applicability of VAMS to study the bioavailability of drug formulations in rats. Methods Four itraconazole-containing formulations were successively administered to rats with a wash-out period of one week. VAMS was used to collect 14 whole blood samples of only 10 μL each within a time frame of 48 hours after administration of the different drug formulations. Particular attention was paid to sample preparation and stability. The extraction of itraconazole and its main metabolite hydroxy-itraconazole was optimized to provide a high recovery and minimal matrix effects. A developed and validated LC–MS/MS method was used for the quantification of the two compounds. Pharmacokinetic profiles for the different formulations were constructed and compared. Results The stability of itraconazole and hydroxy-itraconazole in dried VAMS samples of whole rat blood could not be guaranteed for more than a day when the samples were stored at room temperature. However, samples were stable for at least two weeks when stored at -80°C after sample preparation. Differences in pharmacokinetic profiles were observed for the tested drug formulations. Whole blood concentrations of itraconazole and its main metabolite were significantly higher after administration of three in-house produced formulations compared to concentrations obtained with a commercially available product. Moreover, these in vivo results could be partly related to in vitro dissolution rates of the various formulations. Conclusions VAMS is an attractive approach for bioavailability studies. Due to the low blood volumes per sampling point, the same rats can be used to compare various drug formulations. Therefore, the number of required animals can be drastically reduced. Moreover, this helps to suppress the inter-individual variability and strengthens the validity of results. [less ▲]

Detailed reference viewed: 36 (3 ULiège)
Full Text
Peer Reviewed
See detailSupercritical Fluid Chromatography in Traditional Chinese Medicine Analysis
Huang, Yang ULiege; Tang, Guangyun; Zhang, Tingting et al

in Journal of Pharmaceutical and Biomedical Analysis (2017)

Traditional Chinese medicines (TCMs) are gaining increasing popularity throughout the world due to their long historical clinical practices. Highly efficient analytical separation tools are essential for ... [more ▼]

Traditional Chinese medicines (TCMs) are gaining increasing popularity throughout the world due to their long historical clinical practices. Highly efficient analytical separation tools are essential for investigating the mysterious properties of TCMs and their quality control. Supercritical fluid chromatography (SFC) showed a great potential in TCM analysis for both nonpolar and polar components. In this paper, an overview of the experimental conditions (i.e. detection mode, stationary phase, mobile phase composition, pressure and temperature) used in SFC for achiral separations of TCM components is presented and recent applications to the analysis of different classes of compounds extracted from TCMs, such as lipids, terpene and terpenoids, phenolic compounds, flavonoids, alkaloids, saponins and carbohydrates, will be briefly described. [less ▲]

Detailed reference viewed: 19 (3 ULiège)
Full Text
Peer Reviewed
See detailSimultaneous Determination of Free Amino Acid Content in Different Teas using Supercritical Fluid Chromatography Coupled with Single Quadrupole Mass Spectrometry
Huang, Yang ULiege; Fillet, Marianne ULiege; Crommen, Jacques ULiege et al

Poster (2017, July 02)

Tea (Camellia sinensis L.) is a complex mixture containing a wide range of biological activities and has been used as widely consumed beverages and natural medicine for over thousand years [1-2]. In this ... [more ▼]

Tea (Camellia sinensis L.) is a complex mixture containing a wide range of biological activities and has been used as widely consumed beverages and natural medicine for over thousand years [1-2]. In this study, a novel method for high-performance liquid chromatography with mass spectrometry (SFC-MS) has been developed to simultaneously determine the contents of 11 free amino acids in different types of teas (pu-erh tea, green tea, black tea and oolong tea). The separation conditions for the selected amino acids were carefully optimized such as the column type, temperature and backpressure, the type of additive. The best compromise for tested analytes in terms of chromatographic performance was obtained when water (5%) and trifluoroacetate acid (0.4%) were added to the supercritical carbon dioxide/methanol mobile phase. Finally, the developed SFC-MS method was successfully applied to the analysis of the 11 amino acids present in the teas and fully validated as well. The results indicated a good linearity (r ≥0.995), precision (RSD≤ 2.99%), stability (RSD≤ 2.88%) and accuracy (91.95%~107.99%). The limits of detection ranged from 1.42 to 14.69 ng/mL, respectively, while the limits of quantification were between 4.53 and 47.0 ng/mL. The content of the amino acids in six different tea samples were also determined and presented some difference basing on the fermentation processes. The proposed SFC-MS method showed a great potential in further investigations to differentiate tea varieties [less ▲]

Detailed reference viewed: 32 (1 ULiège)
Full Text
See detailQuality control of insulin formulations: API , protamine and aggregates follow-up
Demelenne, Alice ULiege; Napp, Aurore ULiege; Lamalle, Caroline et al

Poster (2017, June 21)

The prevalence of diabetes is increasing every year and insulin preparations are mostly prescribed for treatment of both type 1 and type 2 diabetes. Since these biopharmaceutical formulations are ... [more ▼]

The prevalence of diabetes is increasing every year and insulin preparations are mostly prescribed for treatment of both type 1 and type 2 diabetes. Since these biopharmaceutical formulations are expensive and require a prescription, they are an important target for counterfeiting in developing countries. Therefore, there is a need for fast and efficient methods for quality control of biopharmaceutical products such as insulin formulations. A fully validated micellar electrokinetic chromatography (MEKC) method was developed for quantification of human insulin and NPH insulin (insulin combined with protamine) in formulations. The BGE used was made of 50 mM ammonium acetate (pH 9.0), 20 mM Sodium dodecyl sulfate and 13 % (v/v) acetonitrile and samples were introduced at the short capillary end allowing a separation of insulin and two major excipients (phenol and m-cresol) within 3 minutes. This method was compared with HPLC method using a mobile phase composed of water with 0.1% formic acid / acetonitrile with 0.1 % formic acid in gradient mode. Secondly a MEKC method was also optimized to analyze protamine peptides in insulin formulations. The major protamine peptides could be separated using a BGE made of 100 mM phosphate buffer (pH 2) with 50 mM Thesit®. This method was used to check conformity of protamine in commercially available formulations. Finally, different approaches were investigated in order to follow insulin aggregation. Indeed, insulin is prone to unfold when submitted to denaturating factors as temperature, ionic strength, agitation and pH. An accumulation of unfolds protein in bloodstream results in a high tendency to aggregate and form amyloid fibrils. A deposit of those fibrils in the subcutaneous tissue leads to a complication called “insulin-derived amyloidosis”. On the other hand, during its production, insulin is often subjected to extreme conditions making aggregation, as well as protein stability, important parameters to be controlled during its quality control. In this study, insulin aggregates were generated after optimization of incubation conditions (pH, temperature, agitation…). Those aggregates were then analyzed by size-exclusion chromatography (SEC) and capillary electrophoresis (CE). We showed that capillary gel electrophoresis (CGE) is a promising technique to analyze covalent aggregates of insulin due to the fact that it separates the aggregates according to their size and not to their size/charge ratio. The use of a laser-induced fluorescence detector was also found attractive to enhance the sensitivity of the method. [less ▲]

Detailed reference viewed: 31 (14 ULiège)
Peer Reviewed
See detailOptimization of an electrophoretic approach for the screening and the development of new antithrombotic drugs
Farcas, Elena ULiege; Bouckaert, Charlotte; Servais, Anne-Catherine ULiege et al

Conference (2017, June 20)

The discovery of lead compounds that can modulate the activity of a biological target is essential to provide efficient pharmacological tools and to serve as starting points for new drug generations ... [more ▼]

The discovery of lead compounds that can modulate the activity of a biological target is essential to provide efficient pharmacological tools and to serve as starting points for new drug generations. Fragment-based drug discovery (FBDD) approach is an attractive tool for the identification of new selective inhibitors of a target of interest, but its success largely depends on the ability to develop screening bioassays capable to detect and gauge weak affinity binders. To achieve this goal, we investigated capillary electrophoresis (CE) for identifying and ranking fragments from an initial library. Indeed, due to its ability to evaluate weak interactions, CE seems to be promising for fragment-based screening. This technique is a powerful analytical tool with a unique separation mechanism, speed, efficiency and versatility. Its main advantages are low protein consumption, higher throughput compared to NMR and X-ray crystallography and the fact that screening can be carried out using native protein in physiological solution without the need of immobilization. We developed a proof of concept study on thrombin, a serine protease implicated in the coagulation cascade using affinity capillary electrophoresis (ACE) for ranking fragments from an initial library. For this study, we followed a probe ligand, benzamidine, and we investigated interactions with the target by monitoring the changes of its electrophoretic mobility upon binding. The first step of this study consisted in the optimization of the experimental conditions suitable for the CE method (target and probe ligand concentrations, separation buffer composition, voltage, separation effective length, target partial filling…). Then, numerous thrombin inhibitors with a wide range of inhibitory potency (i.e. Ki 200 µM – 5 nM) were tested to validate our system demonstrating the possibility to fish binders in the optimized conditions. We also checked the absence of non-specific binding with the target using the inactivated enzyme at the binding site. It is noteworthy that in this operating system (ACE assay), binding occurs in free solution using physiological buffers, thus preventing artifacts that may result from target immobilization, which is a requirement for some techniques such as SPR. [less ▲]

Detailed reference viewed: 36 (15 ULiège)
Peer Reviewed
See detailOptimiaztion of an electrophoretic approach for the screening and the development of new antithrombotic drugs
Farcas, Elena ULiege; Bouckaert, Charlotte; Servais, Anne-Catherine ULiege et al

Poster (2017, June 19)

The discovery of lead compounds that can modulate the activity of a biological target is essential to provide efficient pharmacological tools and to serve as starting points for new drug generations ... [more ▼]

The discovery of lead compounds that can modulate the activity of a biological target is essential to provide efficient pharmacological tools and to serve as starting points for new drug generations. Fragment-based drug discovery (FBDD) approach is an attractive tool for the identification of new selective inhibitors of a target of interest, but its success largely depends on the ability to develop screening bioassays capable to detect and gauge weak affinity binders. To achieve this goal, we investigated capillary electrophoresis (CE) for identifying and ranking fragments from an initial library. Indeed, due to its ability to evaluate weak interactions, CE seems to be promising for fragment-based screening. This technique is a powerful analytical tool with a unique separation mechanism, speed, efficiency and versatility. Its main advantages are low protein consumption, higher throughput compared to NMR and X-ray crystallography and the fact that screening can be carried out using native protein in physiological solution without the need of immobilization. We developed a proof of concept study on thrombin, a serine protease implicated in the coagulation cascade using affinity capillary electrophoresis (ACE) for ranking fragments from an initial library. For this study, we followed a probe ligand, benzamidine, and we investigated interactions with the target by monitoring the changes of its electrophoretic mobility upon binding. The first step of this study consisted in the optimization of the experimental conditions suitable for the CE method (target and probe ligand concentrations, separation buffer composition, voltage, separation effective length, target partial filling…). Then, numerous thrombin inhibitors with a wide range of inhibitory potency (i.e. Ki 200 µM – 5 nM) were tested to validate our system demonstrating the possibility to fish binders in the optimized conditions. We also checked the absence of non-specific binding with the target using the inactivated enzyme at the binding site. It is noteworthy that in this operating system (ACE assay), binding occurs in free solution using physiological buffers, thus preventing artifacts that may result from target immobilization, which is a requirement for some techniques such as SPR. [less ▲]

Detailed reference viewed: 70 (6 ULiège)
Full Text
Peer Reviewed
See detailDEVELOPMENT AND VALIDATION OF A FAST SFC METHOD FOR THE ANALYSIS OF FLAVONOIDS IN PLANT EXTRACTS
Huang, Yang ULiege; Jiang, Zhengjin; Fillet, Marianne ULiege et al

Poster (2017, June 18)

Flavonoids from plants always show a wide range of biological activities [1-2]. In the present study, a rapid and highly efficient supercritical fluid chromatography (SFC) method was developed for the ... [more ▼]

Flavonoids from plants always show a wide range of biological activities [1-2]. In the present study, a rapid and highly efficient supercritical fluid chromatography (SFC) method was developed for the separation of 12 flavonoids. After careful optimization, the 12 flavonoids were baseline separated on a ZORBAX RX-SIL column using gradient elution. A 0.1% phosphoric acid solution in methanol was found to be the most suitable polar mobile phase component for the separation of flavonoids. From the viewpoint of retention and resolution, a backpressure of 200 bar and a temperature of 40 °C were shown to give the best results. Compared with a previously developed reverse phase liquid chromatography method, the SFC method could provide flavonoid separations that were about three times faster, while maintaining good peak shape and comparable peak efficiency. This SFC method was validated and applied to the analysis of five flavonoids (kaempferol, luteolin, quercetin, luteoloside, buddleoside) present in Chrysanthemum morifolium Ramat. from different cultivars (Chuju, Gongju, Hangju, Boju). The results indicated a good repeatability and sensitivity for the quantification of the five analytes with RSDs for overall precision lower than 3%. The limits of detection ranged from 0.73 to 2.34 μg/mL, while the limits of quantification were between 2.19 and 5.86 μg/mL. The method showed that SFC could be employed as a useful tool for the quality assessment of Traditional Chinese medicines (TCMs) containing flavonoids as active components. [less ▲]

Detailed reference viewed: 13 (3 ULiège)
Full Text
Peer Reviewed
See detailWhole blood microsampling for the quantitation of estetrol without derivatization by liquid chromatography-tandem mass spectrometry
Nys, Gwenaël ULiege; Gallez, Anne ULiege; Kok, Miranda ULiege et al

in Journal of Pharmaceutical & Biomedical Analysis (2017), 140

Detailed reference viewed: 50 (25 ULiège)
Peer Reviewed
See detailSeparation of FLEC diastereomers by CE vs. LC approaches in the context of neurometabolomics
Moldovan, Radu-Cristian ULiege; Bodoki, Ede; Servais, Anne-Catherine ULiege et al

Poster (2017, June)

Some of the D-amino acids (D-Ser, D-Asp, D-Glu) have gained an increasing attention during the last decades, due to the discovery of their role as neurotransmitters and their implication in different ... [more ▼]

Some of the D-amino acids (D-Ser, D-Asp, D-Glu) have gained an increasing attention during the last decades, due to the discovery of their role as neurotransmitters and their implication in different neurological pathologies (Alzheimer’s disease, schizophrenia etc.). Nevertheless, their use as biomarkers is particularly relevant when correlated with the levels of other neurotransmitters. In order to develop a fast and efficient separation method widely accessible for the quantitation of these molecules, we used only common separation tools such as RP-18 stationary phases for reversed phase liquid chromatography (RP-LC) or bare fused capillaries for capillary zone electrophoresis (CZE). For achieving chiral resolution, a derivatization procedure was implemented. (-)-FLEC was the chiral derivatization agent of choice due to its fast and quantitative reaction with primary and secondary amines and the ability of performing in-capillary derivatization. Moreover, the derivatization process implies only a simple mix of the sample and reagent, at room temperature. The separation of the FLEC derivatives of several biologically relevant D- and L- amino acids (Asp, Glu, Ser, Tyr, Trp, Phe, His) together with certain neurotransmitter molecules have been optimized using CZE or RP-LC, chiral resolution being achievable for all amino acids of interest. By the CZE approach the running buffer’s pH turned out to be critical in achieving baseline separation of the targeted analytes. The derivatives of most amino acids could be separated using 60mM acetate buffer at pH 5, while for Asp derivatives the separation could be achieved only at pH 4. Being stronger bases, a third run at a more alkaline pH was needed for the separation of the remainder neurotransmitters. Moreover, the implemented in-capillary derivatization allows a fast and fully automated separation procedure. As for the RP-LC approach 50 mM acetate buffer in combination with an organic modifier (methanol, acetonitrile or tetrahydrofuran (THF)) was tested as mobile phase using gradient elution. Once again, the strong influence of pH on the resolution was observed. The organic modifier nature was of critical importance, where only THF enabled baseline resolution for all amino acid derivatives. [less ▲]

Detailed reference viewed: 31 (7 ULiège)
Full Text
Peer Reviewed
See detailEccentric training for tendon healing after lesion: a rat model
Kaux, Jean-François ULiege; Libertiaux, Vincent ULiege; Leprince, Pierre ULiege et al

in American Journal of Sports Medicine (2017), 45(6), 1440-1446

BACKGROUND:The tendon is a dynamic entity that remodels permanently. Platelet-rich plasma (PRP) injection has been shown to have a beneficial effect on tendon healing after lesion in rats. Furthermore ... [more ▼]

BACKGROUND:The tendon is a dynamic entity that remodels permanently. Platelet-rich plasma (PRP) injection has been shown to have a beneficial effect on tendon healing after lesion in rats. Furthermore, eccentric exercise seems to improve the mechanical quality of the tendon. HYPOTHESIS:A combination of PRP injection and eccentric training might be more effective than either treatment alone. STUDY DESIGN:Controlled laboratory study. METHODS:Adult male rats were anesthetized, an incision was performed in the middle of their left patellar tendon and an injection of physiological fluid (PF) or homologous PRP was randomly made at the lesion level. The rats were then divided into 2 groups: the eccentric group, undergoing eccentric training 3 times a week, and the untrained group, without any training. Thus, 4 groups were compared. After 5 weeks, the tendons were removed and their ultimate tensile strength and energy were measured. Tendons were frozen for proteomic analyses when all biomechanical tests were completed. Statistical analysis was performed with linear mixed effect models. RESULTS:No significant difference was found between the treatments using PF injection or PRP injection alone. However, the value of the ultimate tensile force at rupture was increased by 4.5 N (108% of control, P = .006) when eccentric training was performed. An intragroup analysis revealed that eccentric training significantly improved the ultimate force values for the PRP group. Proteomic analysis revealed that eccentric training led to an increase in abundance of several cytoskeletal proteins in the PF group, while a decrease in abundance of enzymes of the glycolytic pathway occurred in the PRP treated groups, indicating that this treatment might redirect the exercise-driven metabolic plasticity of the tendon. CONCLUSION: Eccentric training altered the metabolic plasticity of tendon and led to an improvement of injured tendon resistance regardless of the treatment injected (PF or PRP). CLINICAL RELEVANCE:This study demonstrates the necessity of eccentric rehabilitation and training in cases of tendon lesion regardless of the treatment carried out. [less ▲]

Detailed reference viewed: 72 (12 ULiège)
Full Text
Peer Reviewed
See detailSimultaneous analysis of nucleobases, nucleosides and ginsenosides in ginseng extracts using supercritical fluid chromatography coupled with single quadrupole mass spectrometry
Huang, Yang ULiege; Zhang, Tingting; Zhao, Yumei et al

in Journal of Pharmaceutical and Biomedical Analysis (2017), 144(213), 219

Nucleobases, nucleosides and ginsenosides, which have a significant impact on the physiological activity of organisms, are reported to be the active components of ginseng, while they are less present in ... [more ▼]

Nucleobases, nucleosides and ginsenosides, which have a significant impact on the physiological activity of organisms, are reported to be the active components of ginseng, while they are less present in ginseng extracts. Few analytical methods have been developed so far to simultaneously analyze these three classes of compounds with different polarities present in ginseng extracts. In the present study, a simple and efficient analytical method was successfully developed for the simultaneous separation of 17 nucleobases, nucleosides and ginsenosides in ginseng extracts using supercritical fluid chromatography coupled with single quadrupole mass spectrometry (SFC-MS). The effect of various experimental factors on the separation performance, such as the column type, temperature and backpressure, the type of modifier and additive, and the concentration of make-up solvent were systematically investigated. Under the selected conditions, the developed method was successfully applied to the quality evaluation of 14 batches of ginseng extracts from different origins. The results obtained for the different batches indicate that this method could be employed for the quality assessment of ginseng extracts [less ▲]

Detailed reference viewed: 22 (1 ULiège)
See detailLc-chip versus UHPLC-tandem mass spectrometry for the quantitation of estetrol and estradiol without derivatization after whole blood microsampling
Nys, Gwenaël ULiege; Servais, Anne-Catherine ULiege; Pequeux, Christel ULiege et al

Conference (2017, March 29)

the aim of this work was to conduct a PK study on mice to select the most appropriate administration route for E2 and E4 formulations. To achieve this goal, a reference method for the quantitation of both ... [more ▼]

the aim of this work was to conduct a PK study on mice to select the most appropriate administration route for E2 and E4 formulations. To achieve this goal, a reference method for the quantitation of both estrogens after whole blood microsampling was developed and validated on a UHPLC-MS/MS system. This reference method was later transferred on LC-chip device and both methods were compared in terms of analytical parameters such as response function, accuracy, precision, trueness and limit of quantification. [less ▲]

Detailed reference viewed: 23 (2 ULiège)