A double-cartridge SPE-HPLC-UV method for monitoring a humanfriendly anticancer in plasma: Ketoglutarate levels in metastatic carcinoma

Poster (2010)

We present a fully validated HPLC-UV assay for the concurrent quantification of ketoglutaric acid and hydroxymethylfurfural, a ‘targeted therapy’ composition inducing a synergistic metabolic distress to ... [more ▼]

We present a fully validated HPLC-UV assay for the concurrent quantification of ketoglutaric acid and hydroxymethylfurfural, a ‘targeted therapy’ composition inducing a synergistic metabolic distress to the tumoral microenvironment. The analytes were exclusively extracted from the biomatrix via a combined-cartridge solid phase extraction assembly. The method is based on derivatizing both analytes with 2-nitrophenylhydrazine directed to their chemically divergent but commonly occurring carbonyl function. The reaction is kinetically catalyzed. Acidifying the buffered eluate post-extraction is critical for the feasibility of the reaction. The chromatographic separation is successfully accomplished on octyl columns in less than 15 min at 330 nm using 0.028% TFAA-methanol-acetonitrile (58:32:10, v/v) as eluant. The assay was validated using the concept of accuracy profile. The selectivity of the method was demonstrated in pre- and post-dosed patients from a pilot study. Quality control samples were prepared and analyzed during the routine use of the method. Life samples collected from patients enduring oesophageal and breast carcinoma with lung metastases were monitored for ketoglutarate in a trial to correlate its plasma levels with the malignancy. [less ▲]

Développement et validation d'une méthode de dosage de la glucosamine par SPE/HILIC/MS dans le plamsa de chien

Poster (2009, December 01)

Estimation of the Stability of Parathyroid Hormone when Stored at -80°C for a Long Period

in Clinical Journal of the American Society of Nephrology (2009), 4(12), 1988-92

Active content determination of non-coated pharmaceutical pellets by near infrared spectroscopy: Method development, validation and reliability evaluation

Poster (2009, November)

Estimation de l’incertitude à partir de la stratégie de l’erreur totale : Application pour des méthodes internes et des méthodes normatives.

Poster (2009, October)

Validation des méthodes d'analyse pharmaceutique et biopharmaceutique

Learning material (2009)

Introduire les notions et concepts fondamentaux pour la validation d'une méthode analytique quantitative. A cette occasion sont définis les critères générales utilisées pour attester de la validité des ... [more ▼]

Introduire les notions et concepts fondamentaux pour la validation d'une méthode analytique quantitative. A cette occasion sont définis les critères générales utilisées pour attester de la validité des procédures analytiques. Différents protocoles de validation sont également illustrés. Dans ce contexte, l'objectif de la validation est reprécisé. Il paraît raisonnable de prétendre que celui-ci est de donner aux laboratoires ainsi qu'aux autorités compétentes les garanties que chaque mesure qui sera réalisée ultérieurement en routine, une fois la procédure validée, sera suffisamment proche de la "vraie valeur" inconnue de l'échantillon ou du moins comprise dans une limite acceptable, en fonction de la finalité de la procédure. Le but est de minimiser le risque tant au niveau du producteur que du futur consommateur. Par conséquent, l'objectif de la validation n'est pas simplement d'obtenir des estimateurs du biais et de la fidélité. Toutefois, il n'en reste pas moins que ces paramètres sont des éléments indispensables à l'établissement des garanties précitées. [less ▲]

A new statistical method for the automated detection of peaks in UV-DAD chromatograms of a sample mixture

in Talanta (2009), 79

One of the major issues within the context of the fully automated development of chromatographic methods consists of the automated detection and identification of peaks coming from complex samples such as ... [more ▼]

One of the major issues within the context of the fully automated development of chromatographic methods consists of the automated detection and identification of peaks coming from complex samples such as multi-component pharmaceutical formulations or stability studies of these formulations. The same problem can also occur with plant materials or biological matrices. This step is thus critical and time-consuming, especially when a Design of Experiments (DOE) approach is used to generate chromatograms. The use of DOE will often maximize the changes of the analytical conditions in order to explore an experimental domain. Unfortunately, this generally provides very different and “unpredictable” chromatograms which can be difficult to interpret, thus complicating peak detection and peak tracking (i.e. matching peaks among all the chromatograms). In this context, Independent Components Analysis (ICA), a new statistically based signal processing methods was investigated to solve this problem. The ICA principle assumes that the observed signal is the resultant of several phenomena (known as sources) and that all these sources are statistically independent. Under those assumptions, ICA is able to recover the sources which will have a high probability of representing the constitutive components of a chromatogram. In the present study, ICA was successfully applied for the first time to HPLC–UVDAD chromatograms and it was shown that ICA allows differentiation of noise and artifact components from those of interest by applying clustering methods based on high-order statistics computed on these components. Furthermore, on the basis of the described numerical strategy, itwas also possible to reconstruct a cleaned chromatogram with minimum influence of noise and baseline artifacts. This can present a significant advance towards the objective of providing helpful tools for the automated development of liquid chromatography (LC) methods. It seems that analytical investigations could be shortened when using this type of methodologies. [less ▲]

Betamethasone in cyclodextrin in deformable liposomes for dermal applications: ex vivo diffusion studies

Poster (2009, June 07)

VALIDATION AND ACCURACY PROFILES OF THE LIAISON BAP_OSTASE (DIASORIN), A NEW METHOD FOR THE DETERMINATION OF BONE ALKALINE PHOSPHATASE

in Clinical Chemistry & Laboratory Medicine (2009, June), 47(51),

Development and validation of a sensitive SPE/LC/MS method for the determination of glucosamine in dog plasma

Poster (2009, June)