References of "Fillet, Marianne"
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See detailImmune Recovery after Allogeneic Hematopoietic Stem Cell Transplantation following Flu-TBI versus TLI-ATG Conditioning
HANNON, Muriel ULg; BEGUIN, Yves ULg; Ehx, Grégory ULg et al

in Clinical Cancer Research : An Official Journal of the American Association for Cancer Research (in press)

Purpose: A conditioning regimen for allogeneic hematopoietic cell transplantation (HCT) combining total lymphoid irradiation (TLI) plus anti-thymocyte globulin (ATG) has been develop to induce graft ... [more ▼]

Purpose: A conditioning regimen for allogeneic hematopoietic cell transplantation (HCT) combining total lymphoid irradiation (TLI) plus anti-thymocyte globulin (ATG) has been develop to induce graft-versus-tumor effects without graft-versus-host disease (GVHD). Experimental Design: We compared immune recovery in 53 patients included in a phase II randomized study comparing nonmyeloablative HCT following either fludarabine plus 2 Gy total body irradiation (TBI arm, n=28) or 8 Gy TLI plus anti-thymocyte globulin (TLI arm, n=25). Results: In comparison to TBI patients, TLI patients had a similarly low 6-month incidence of grade II-IV acute GVHD, a lower incidence of moderate/severe chronic GVHD (P=0.02), a higher incidence of CMV reactivation (P<0.001), and a higher incidence of relapse (P=0.01). While recovery of total CD8+ T cells was similar in the two groups, with median CD8+ T cell counts reaching the normal values 40-60 days after allo-HCT, TLI patients had lower percentages of naïve CD8 T cells. Median CD4+ T cell counts did not reach the lower limit of normal values the first year after allo-HCT in the two groups. Further, CD4+ T cell counts were significantly lower in TLI than in TBI patients the first 6 months after transplantation. Interestingly, while median absolute regulatory T cell (Treg) counts were comparable in TBI and TLI patients, Treg/naïve CD4+ T cell ratios were significantly higher in TLI than in TBI patients the 2 first years after transplantation. Conclusions: Immune recovery differs substantially between these two conditioning regimens possibly explaining the different clinical outcomes observed (NCT00603954). [less ▲]

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See detailSimultaneous determination of insulin and its analogues in pharmaceutical formulations by micellar electrokinetic chromatography
Lamalle, Caroline ULg; Servais, Anne-Catherine ULg; RADERMECKER, Régis ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (2015)

A simple and efficient MEKC method was developed to simultaneously determine human insulin, its five analogues, the main degradation products and the excipients usually present in injection formulations ... [more ▼]

A simple and efficient MEKC method was developed to simultaneously determine human insulin, its five analogues, the main degradation products and the excipients usually present in injection formulations. A very fast method with a total analysis time of 3 min was then successfully validated for the analysis of human insulin and the quality control of different commercial formulations was carried out. [less ▲]

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See detailThe emergence of metabolomics as a key discipline in the drug discovery process
Fillet, Marianne ULg; Frederich, Michel ULg

in Drug Discovery Today: Technologies (2015)

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See detailTSC2 and 14-3-3 proteins down-regulate a RIP3 dependent PDT-induced Necroptosis in Glioblastoma
Fettweis, Grégory ULg; Coupienne, Isabelle; Fillet, Marianne ULg et al

Poster (2014, October)

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See detailComprehensive plasma profiling for the characterization of graft-versus-host disease biomarkers
De Bock, Muriel; BEGUIN, Yves ULg; Leprince, Pierre ULg et al

in Talanta (2014), 125

Acute graft-versus-host disease (aGVHD) remains a life-threatening complication of hematopoietic stem cell transplantation (HSCT), limiting its application. To optimize management of aGVHD and reduce ... [more ▼]

Acute graft-versus-host disease (aGVHD) remains a life-threatening complication of hematopoietic stem cell transplantation (HSCT), limiting its application. To optimize management of aGVHD and reduce therapy-related toxicity, early specific markers are needed. The main objective of this study was thus to uncover diagnostic biomarkers comparing plasma protein profiles of patients at the time of acute GVHD diagnosis and of patients undergoing HSCT without aGVHD. Additional analysis of samples taken 15 days before aGVHD diagnosis was also performed to evaluate the potential of the newly discovered biomarkers for early diagnosis. To extract a maximum of information from plasma samples, we used three complementary proteomic approaches, namely 2D-DIGE, SELDI-TOF-MS and 2D-LC-MSE. We identified and confirmed by means of a independent techniques, the differential expression of several proteins indicating significantly increased inflammation response and disturbance in the coagulation cascade. The variation of these proteins was already observed 15 days before GVHD diagnosis, suggesting the potential early detection of the disease before symptoms appearance. Finally, logistic regression analysis determines a composite biomarker panel comprising fibrinogen, fragment of fibrinogen beta chain, SAA, prothrombin fragments, apolipoprotein A1 and hepcidin that optimally discriminated patients with and without GVHD. The area under the receiver operating characteristic curve distinguishing these 2 groups was 0.95. [less ▲]

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See detailGalectin-3: a new promising cardiac biomarker in sports endurance?
LE GOFF, Caroline ULg; Devaux, Séverine; BREVERS, Eric ULg et al

in Cardiovascular Research (2014, July), 103(Supplement 1), 255

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See detailDéveloppement de méthodes séparatives pour détecter la contrefaçon de molécules biosynthétiques comme l'insuline et les GHRP
Lamalle, Caroline ULg; Baptiste, Emeline; Marini Djang'Eing'A, Roland ULg et al

in Spectra Analyse (2014), 43

Counterfeiting is a widespread problem in the world. The medicines, like insulin or GHRP, need a strict quality control. Capillary electrophoresis and liquid chromatography methods were developed to ... [more ▼]

Counterfeiting is a widespread problem in the world. The medicines, like insulin or GHRP, need a strict quality control. Capillary electrophoresis and liquid chromatography methods were developed to analyze these peptides. The human insulin and its different analogues (lispro, aspart, glulisin, glargin and detemir) were separated by MEKC within 15 minutes. The GHRP-2 and -6 were separated by HPLC also in 15 minutes. Several samples of GHRP-6 were analyzed and non-compliances were reported. These analytical approaches seem to be promising to fight against the counterfeiting of such medicines. [less ▲]

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See detailCardiac troponins and natriuretic peptides in runners: useful for cardiac risk screening ?
LE GOFF, Caroline ULg; Kaux, Jean-François ULg; Fillet, Marianne ULg et al

in British Journal of Sports Medicine (2014, April), 48(7), 173

Background Cardiac troponins (cTn) are considered as the best biomarkers for detection of myocardial cell injury and NT-proBNP as the best for the cardiac insufficiency. Objective Our aim was to compare ... [more ▼]

Background Cardiac troponins (cTn) are considered as the best biomarkers for detection of myocardial cell injury and NT-proBNP as the best for the cardiac insufficiency. Objective Our aim was to compare cTnT and NT-proBNP levels before and after the stress tests, in sportive subjects. Design Prospective, cohort study. Setting Amateur marathon runners and ultrarunners. Patients 28 subjects (26 men, 42.5±11 yrs) were enrolled. Interventions Subjects ran the Maasmarathon (42.195 kilometers) and 33 subjects (33 men, 45.7±9.3 yrs) ran the Ultratour of Liège (Belgium; 67 km). All subjects gave their informed consent. We took blood sample before (T0), just after (T1) and 3 hours after the race (T3). Main outcome measurements cTnT concentrations were measured by high sensitive methods (hsTnT, Roche Diagnostics) on heparin plasma. The NT-proBNP was also determined with the kit Roche on heparin plasma. All statistical analyses were performed using Medcalc version 8.1 for Windows. P-value <.01 was regarded as statistically significant. Results A significant difference between hsTnT concentrations at T0 and T1 (P<.001), and between T0 and T3 (P<.001) for NT-proBNP have been observed, but not between T1 and T3. This observation appeared only after a strenuous exercise. However, up to now this type of exercise is not reproducible easily in a laboratory. Moreover, nobody knows if these observations would have cardiac consequences at long terms. Conclusion Measurement of cardiac troponins by high sensitive methods allows detecting significant release of biomarkers from the heart during exercise. The value of NT-proBNP are also significant but less than TnThs. We think that the TnThs could be an interesting tool in the future to help sport medicine to detect risk of developing a cardiac problem in the future or a sudden death. [less ▲]

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See detailTwo biomarkers for the screening of cardiac risk among runners ?
LE GOFF, Caroline ULg; Kaux, Jean-François ULg; Fillet, Marianne ULg et al

in British Journal of Sports Medicine (2014, April), 48(7), 174

Background Heart-type fatty acid-binding protein (H-FABP) is a low molecular weight protein involved in the intracellular uptake and buffering of long chain fatty in the myocardium. Troponin T is a ... [more ▼]

Background Heart-type fatty acid-binding protein (H-FABP) is a low molecular weight protein involved in the intracellular uptake and buffering of long chain fatty in the myocardium. Troponin T is a component of the contractile apparatus of the striated musculature. Both are early markers for acute coronary syndrome. Objective The aim of our study was to compare the results obtained with the H-FABP and the highly sensitive cardiac troponins (hsTnT) and to test their cardiospecificity in healthy runners. Design Prospective, cohort study. Setting Amateur marathon runners. Patients 23 runners (marathon) were enrolled. Interventions We drowned blood samples at three times: just before (T0), just after (T1), and three hours after the end of the race (T3). Main outcome measurements H-FABP and hs-TnT were performed according to the manufacturer's instructions. A linear regression was calculated to observe if there is any correlation between the two biomarkers. Values above the 95th percentile for H-FABP (2.5 ng/mL) and the 99th percentile for hsTnT (14 ng/L) were considered as positive. Results At T0, none of the subjects were positive for hsTnT but 35% were positive for H-FABP; at T1, 83% for hsTnT and 100% for H-FABP; at T3, 83% for hsTnT and 96% for H-FABP. At T0, the regression equation was H-FABP T0=3.9454–0.1001×hsTnT T0; at T1: H-FABP T1=51.838–1.7026×hsTnT T1; at T3: H-FABP T3=47.977–1.6193×hsTnT T3. No correlation was observed between the 2 biomarkers. Conclusion We observed a significant increase of H-FABP and hsTnT in runners. These markers are independent to each other. These values could biologically correspond to a heart ischemia. These biomarkers could be helpful for the screening of cardiac risk among runners. [less ▲]

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See detailMicellar electrokinetic chromatography against the counterfeiting of insulin formulations
Lamalle, Caroline ULg; Servais, Anne-Catherine ULg; Crommen, Jacques ULg et al

Poster (2014)

Insulin plays an important role in the homeostasis of blood glucose concentration. A deficiency of this hormone causes diabetes, which can be treated by subcutaneous injection of synthetic insulin ... [more ▼]

Insulin plays an important role in the homeostasis of blood glucose concentration. A deficiency of this hormone causes diabetes, which can be treated by subcutaneous injection of synthetic insulin. Besides human regular insulin, several modified analogues have been developed to accelerate (Lispro, Aspart, Glulisin) or delay (Glargin, Detemir) its absorption. Moreover, protamine is sometimes associated with human, Lispro or Aspart insulin to give a crystalline form, which delays the action of insulin, providing it with a prolonged absorption profile after injection. Diabetes is one of the most common metabolic diseases in the world; its prevalence increases continuously. A lot of patients are therefore concerned with the treatment, which is relatively expensive and requires a prescription. Some pharmaceutical formulations can sometimes be found without prescription on the parallel market but the risk of drug counterfeiting is then considerably increased. The poor quality of these drugs can lead to harmful consequences for the public health. It is therefore essential to develop a suitable method for the identification and quantification of human insulin and its analogues inside formulations. Ortner et al. [1] have already proposed micellar electrokinetic chromatography (MEKC) methods to detect simultaneously human insulin and its five analogues but no quantitative applications were presented. Furthermore, formulations containing protamine were not tested so we included them in our study. The first optimisation step involved the sample preparation procedure. An acidic sample solution (10 mM HCl) was finally selected to solubilise protamine and Glargin. Then the background electrolyte composition was investigated to separate the components present in the formulations. A basic buffer (50 mM ammonium acetate pH 9) was selected, providing an important and stable electroosmotic flow, a negative charge to the insulins and avoiding any adsorption to the capillary wall. The addition of sodium dodecylsulfate (SDS) and acetonitrile (ACN) was also found crucial for selectivity. With 50 mM SDS and 15% ACN the six insulins and the two major excipients (phenol and meta-cresol) were fully separated within 15 minutes. This method was then entirely validated for the human insulin and the quality control of related formulations was performed. The next step will be the validation and the quantification of the other analogues. [less ▲]

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See detailDevelopment and validation of a liquid chromatographic method for the stability study of a pharmaceutical formulation containing voriconazole using cellulose tris(4-chloro-3-methylphenylcarbamate) as chiral selector and polar organic mobile phases.
Servais, Anne-Catherine ULg; Moldovan, Radu-Cristian ULg; Farcas, Elena ULg et al

in Journal of chromatography. A (2014), 1363

The ophthalmic solution of voriconazole, i.e. (2R,3S)-2-(2,4-difluorophenyl)-3-(5-fluoropyrimidin-4-yl)-1-(1H-1,2,4-triazol-1-y l)butan-2-ol, made from an injection formulation which also contains ... [more ▼]

The ophthalmic solution of voriconazole, i.e. (2R,3S)-2-(2,4-difluorophenyl)-3-(5-fluoropyrimidin-4-yl)-1-(1H-1,2,4-triazol-1-y l)butan-2-ol, made from an injection formulation which also contains sulfobutylether-beta-cyclodextrin sodium salt as an excipient (Vfend((R))), is used for the treatment of fungal keratitis. A liquid chromatographic (LC) method using polar organic mobile phase and cellulose tris(4-chloro-3-methylphenylcarbamate) coated on silica as chiral stationary phase was successfully developed to evaluate the chiral stability of the ophthalmic solution. The percentage of methanol (MeOH) in the mobile phase containing acetonitrile (ACN) as the main solvent significantly influenced the retention and resolution of voriconazole and its enantiomer ((2S,3R)-2-(2,4-difluorophenyl)-3-(5-fluoropyrimidin-4-yl)-1-(1H-1,2,4-triazol-1- yl)butan-2-ol). The optimized mobile phase consisted of ACN/MeOH/diethylamine/trifluoroacetic acid (80/20/0.1/0.1; v/v/v/v). The method was found to be selective not only regarding the enantiomer of voriconazole but also regarding the specified impurities described in the monograph from the European Pharmacopoeia. The LC method was then fully validated applying the strategy based on total measurement error and accuracy profiles. Under the selected conditions, the determination of 0.1% of voriconazole enantiomer could be performed. Finally, a stability study of the ophthalmic solution was conducted using the validated LC method. [less ▲]

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See detailIn-capillary derivatization with (-)-1-(9-fluorenyl)ethyl chloroformate as chiral labeling agent for the electrophoretic separation of amino acids.
Fradi, Ines ULg; Farcas, Elena ULg; Said, Azza Ben et al

in Journal of chromatography. A (2014), 1363

An original micellar electrokinetic chromatography (MEKC) method using in-capillary derivatization with a chiral labeling reagent was developed for the separation of amino acid (AA) derivatives. The ... [more ▼]

An original micellar electrokinetic chromatography (MEKC) method using in-capillary derivatization with a chiral labeling reagent was developed for the separation of amino acid (AA) derivatives. The potential of (-)-1-(9-fluorenyl)-ethyl chloroformate (FLEC) as in-capillary derivatization agent is described for the first time. Several parameters for in-capillary derivatization and subsequent MEKC separation were systematically investigated using experimental designs. Firstly experimental conditions for in-capillary derivatization were optimized using face-centered central composite design (FCCD). Mixing voltage and time as well as concentration of the labeling solution were investigated. Efficient labeling was achieved by sequential injection of AAs and FLEC labeling solution followed by the application of a voltage of 0.2kV for 570s. The background electrolyte (BGE) composition was then optimized in order to achieve selectivity. A FCCD was performed with two factors, namely the sodium dodecyl sulfate (SDS) concentration and the percentage of propan-2-ol (IPA). The separation of 12 pairs of derivatized AA (FLEC-AA) diastereomers was achieved with resolution values comprised between 3 and 20. Furthermore, an efficient derivatization and separation of 29 FLEC-AA derivatives were achieved in a single run using a buffer made up of 40mM sodium tetraborate, 21mM SDS and 8.5% IPA. The method was successfully applied to the analysis of spiked artificial cerebrospinal fluid (aCSF) sample. [less ▲]

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See detailNew role for Emerin, a key inner nuclear membrane protein, as an enhancer of the autophagosome formation in the C16-ceramide autophagy pathway.
Deroyer, Céline ULg; Renert, Anne-Françoise; Merville, Marie-Paule ULg et al

in Autophagy (2014)

To date, precise roles of EMD remain poorly described. In this paper, we investigate the role of EMD in the C16-ceramide autophagy pathway. Ceramides are bioactive signalling molecules acting notably in ... [more ▼]

To date, precise roles of EMD remain poorly described. In this paper, we investigate the role of EMD in the C16-ceramide autophagy pathway. Ceramides are bioactive signalling molecules acting notably in the regulation of cell growth, differentiation or cell death. However, the mechanisms by which they mediate these pathways are not fully understood. We found that C16-ceramide induces EMD phosphorylation on its LEM domain through PRKACA. Upon ceramide treatment, phosphorylated EMD binds LC3 leading to an increase of the autophagosomes formation. These data suggest a new role of EMD as an enhancer of autophagosomes formation in the C16-ceramide autophagy pathway in colon cancer cells. [less ▲]

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See detailEVALUATION OF α-SYNUCLEIN AS BIOMARKER OF PARKINSON'S DISEASE
Napp, Aurore ULg; Garraux, Gaëtan ULg; Servais, Anne-Catherine ULg et al

Conference (2013, October 17)

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See detailRunning races: study of the stress and cardiac biomarkers
LE GOFF, Caroline ULg; Kaux, Jean-François ULg; MELON, Pierre ULg et al

in European Journal of Sports Medicine (2013, September), 1(Supplement 1), 212

Background: Cardiac troponins (cTn) are considered as the best biomarkers for detection of myocardial cell injury and NT-proBNP as the best for the cardiac insufficiency. In this study, cTnT was measured ... [more ▼]

Background: Cardiac troponins (cTn) are considered as the best biomarkers for detection of myocardial cell injury and NT-proBNP as the best for the cardiac insufficiency. In this study, cTnT was measured by new commercially available high-sensitive methods in subjects undergoing a marathon and an ultra-trail. Our aim was to compare cTnT and NT-proBNP levels before and after the stress tests, in sportive subjects. Materials and Methods: Twenty eight subjects (26 men, 42.5 ± 11 yo) ran the Maasmarathon (42.195 kilometers) between Visé (Belgium) and Maastricht (The Netherlands) and 33 subjects (33 men, 45.7±9.3yo) ran the Ultratour of Liège (Belgium ; 67 km). We took blood sample before (T0), just after (T1) and 3 hours after the race (T3). In all the patients, cTnT concentrations were measured by high sensitive methods (hsTnT, Roche Diagnostics) on heparin plasma. The NT-proBNP was also determined with the kit Roche on heparin plasma. The protocol was approved by the Ethics Committee of the University of Liège (Belgium). All subjects gave their informed consent. All statistical analyses were performed using Medcalc version 8.1 for Windows. p-value <0.01 was regarded as statistically significant. Results and discussion: A significant difference between hsTnT concentrations at T0 and T1 (p<0.0001), and between T0 and T3 (p<0.001) for NT-proBNP have been observed, but not between T1 and T3. This observation appeared only after a strenuous exercise. However, up to now this type of exercise is not reproducible easily in a laboratory. Moreover, nobody knows if these observations would have cardiac consequences at long terms. Conclusions: Measurement of cardiac troponins by high sensitive methods allows detecting significant release of biomarkers from the heart during exercise. The value of NT-proBNP are also significant but less than TnThs. We think that the TnThs could be an interesting tool in the future to help sport medicine to detect risk of developing a cardiac problem in the future or a sudden death. [less ▲]

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See detailL’électrophorèse capillaire micellaire pour la détermination simultanée de l’insuline et de ses analogues dans des formulations pharmaceutiques
Lamalle, Caroline ULg; Servais, Anne-Catherine ULg; Crommen, Jacques ULg et al

Poster (2013, June)

L’insuline joue un rôle important dans l’homéostasie de la concentration sanguine en glucose. Un déficit de cette hormone cause le diabète (de type I) qui peut être traité par injection sous-cutanée ... [more ▼]

L’insuline joue un rôle important dans l’homéostasie de la concentration sanguine en glucose. Un déficit de cette hormone cause le diabète (de type I) qui peut être traité par injection sous-cutanée d’insuline synthétique. En plus de l’insuline humaine, plusieurs analogues ont été développés pour accélérer son absorption (Lispro, Aspart, Glulisin) ou la retarder (Glargin, Detemir). La protamine est également parfois utilisée avec l’insuline humaine, Lispro ou Aspart pour former un complexe et augmenter la durée d’action. Le diabète est une des maladies métaboliques les plus courantes dans le monde; la prévalence ne cesse de s’élever. Beaucoup de patients sont donc concernés par le traitement qui est relativement cher et nécessite une ordonnance. Certaines formulations pharmaceutiques peuvent être trouvées sans ordonnance sur le marché parallèle mais la possibilité de contrefaçon existe. Et la mauvaise qualité de ces médicaments peut entrainer des conséquences néfastes pour la santé publique. Il est donc essentiel de développer une méthode permettant l’identification et la quantification de l’insuline humaine et de ses analogues. Ortner et al. [1] ont déjà proposé une méthode par électrophorèse capillaire micellaire (MEKC) pour séparer simultanément l’insuline humaine et ses 5 analogues, mais ils n’analysaient pas les formulations à base de protamine. Le nombre de ces formulations n’étant pas négligeable, nous les avons incluses dans notre étude. La première étape d’optimisation a été la préparation de l’échantillon. Une solution acide (0.01M d’HCl) a finalement été choisie pour solubiliser la protamine et la Glargine. Ensuite, la composition du background electrolyte a été investiguée pour séparer les composants des formulations. Un tampon basique (50mM d’acétate d’ammonium à pH 9) a été choisi, engendrant un flux électroosmotique important et stable, une charge négative à l’insuline et empêchant l’adsorption à la paroi du capillaire. L’addition de dodécyl sulfate de sodium et d’acétonitrile s’est ensuite révélée déterminante pour la sélectivité. Les 6 insulines et les 2 excipients majeurs (le phénol et le m-crésol) ont été complètement séparés endéans 15 minutes. La méthode précitée a ensuite été adaptée pour permettre la séparation de chaque insuline et de ses produits de dégradation. [less ▲]

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See detailDéveloppement de méthodes de quantification en milieu complexe par chromatographie liquide microfluidique couplée à la spectrometrie de masse
Houbart, Virginie ULg; Rozet, Eric ULg; Crommen, Jacques ULg et al

Conference (2013, June)

L’hepcidine est un biomarqueur peptidique dont l’intérêt tant comme outil de diagnostic que de suivi de pathologies est de plus en plus solidement établi. Il existe donc une demande forte d’outils ... [more ▼]

L’hepcidine est un biomarqueur peptidique dont l’intérêt tant comme outil de diagnostic que de suivi de pathologies est de plus en plus solidement établi. Il existe donc une demande forte d’outils sensibles et robustes afin de la doser au sein de milieux biologiques tels que le plasma ou le sérum. Une méthode analytique a été développée à l’aide d’un système chromatographique miniaturisé (nanoLC-chip) couplé à un spectromètre de masse permettant d’assurer un dosage de l’hepcidine à la fois sensible et fiable. Lors du développement de cette méthode, il a été constaté que la composition de l’échantillon avait une influence majeure sur la réponse analytique. Or, l’utilisation de systèmes chromatographiques miniaturisés implique souvent l’injection de volumes proportionnellement très importants par rapport aux dimensions du système, ce qui amplifie encore l’impact de sa composition. C’est pourquoi il est capital d’avoir une bonne compréhension des phénomènes qui ont lieu entre l’injection de l’échantillon dans le système chromatographique et la détection par spectrométrie de masse, et particulièrement lors du développement de méthodes analytiques quantitatives. Dans cette étude, nous avons utilisé la planification expérimentale afin de mieux comprendre le comportement chromatographique des peptides, ainsi que les facteurs qui influencent la sensibilité de la méthode développée. Un mélange de peptides a été sélectionné, varié tant du point de vue du poids moléculaire que du point isoélectrique et de l’hydropathie. Un plan de criblage a permis de délimiter le domaine expérimental ainsi que les facteurs significatifs parmi la composition de la phase mobile (proportion et nature de l’agent de paire d’ions) et de l’échantillon en lui-même (nature de l’agent de paire d’ions et proportion de solvant organique). Ensuite, un plan d’expériences factoriel complet a été mis en œuvre afin d’observer plus finement le rôle de chaque facteur ainsi que les interactions éventuelles qui les lient. Certains facteurs ont montré un effet très marqué tant sur l’intensité de la réponse que sur la rétention. Entre autres, la composition de l’échantillon, facteur parfois négligé lors du développement de méthodes, a démontré son importance capitale, en particulier sur les phénomènes de rétention des peptides. Les données obtenues ont également permis de dégager des conditions optimales d’analyse en termes de rétention et de sensibilité. Enfin, une analyse en composantes principales a également été réalisée sur le grand nombre de données récoltées dans le but de mettre en évidence d’éventuels propriétés physicochimiques des peptides qui pourraient avoir un impact significatif sur les réponses étudiées. [less ▲]

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