References of "Ziemons, Eric"
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See detailCritical review of surface-enhanced Raman spectroscopy applications in the pharmaceutical field
Cailletaud, Johan ULiege; De Bleye, Charlotte ULiege; Dumont, Elodie ULiege et al

in Journal of Pharmaceutical & Biomedical Analysis (in press)

Surface-enhanced Raman spectroscopy (SERS) is a sensitive analytical tool used in the pharmaceutical field in recent years. SERS keeps all the advantages of classical Raman spectroscopy while being is ... [more ▼]

Surface-enhanced Raman spectroscopy (SERS) is a sensitive analytical tool used in the pharmaceutical field in recent years. SERS keeps all the advantages of classical Raman spectroscopy while being is more sensitive allowing its use for the detection and the quantification of low-dose substances contained in pharmaceutical samples. However, the analytical performance of SERS is limited due to the difficulty to implement a quantitative methodology correctly validated. Nevertheless, some studies reported the development of SERS quantitative methods especially in pharmaceutical approaches. In this context, this review presents the main concepts of the SERS technique. The different steps that need to be applied to develop a SERS quantitative method are also deeply described. The last part of the present manuscript gives a critical overview of the different SERS pharmaceutical applications that were developed for a non-exhaustive list of pharmaceutical compounds with the aim to highlights the validation criteria for each application. [less ▲]

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See detailPoor quality medicines in Africa: how to combat this real scourge
Marini Djang'Eing'A, Roland ULiege; Sacre, Pierre-Yves ULiege; Ziemons, Eric ULiege et al

Conference (2017, October 04)

Poor (or low) quality medicines remain a crucial problem of public health around the world. They encompass falsified /counterfeit, substandard or degraded drugs. If proportion of 1% is estimated in ... [more ▼]

Poor (or low) quality medicines remain a crucial problem of public health around the world. They encompass falsified /counterfeit, substandard or degraded drugs. If proportion of 1% is estimated in developed countries, they are globally about 10 % of counterfeit drugs according to Food and Drug Administration, with 30% in low income countries and astonishing values (80 %) reported in some African countries. The consequences and dangers of such medicines are therapeutic failure, drug poisoning, microbial resistance or even death. For the pharmaceutical industries, there are loss of image, loss of financial income and employment. There is need to combat this scourge, but most of the time, means are very limited and even lacking. In this context, several means or tools are developed by the ULg Pharmacy Department including the simple ones including organoleptic tests, simple analytical tests such as analytical balance, pHmeter, thin layer chromatography (TLC), UV-visible spectrophotometry to the more complex including liquid chromatography (LC) coupled to UV-Vis detector, or to mass spectrometry, nuclear magnetic resonance, Raman imagery (RIM) and near infrared (NIR) spectroscopy associated with the principal component analysis (PCA). In this way, we have analyzed several suspected samples obtained via the public health authorities of the D.R. Congo, Benin and Rwanda after their seizure or through collaborations. The results are presented by therapeutic class, namely: analgesics: - by using LC and complementary information from victim patients, we were able to discover an abnormal presence of a benzodiazepine at very high doses in paracetamol tablets which was the cause of unusual adverse effects (sedative effects, polyuria and hypotension) in patients who have consumed it; - by using the NIR-PCA, we were able to elucidate the substitution of an excipient (glycerol) by diethylene glycol in paracetamol syrup which caused the death of a hundred babies. antimalarials: - we faced cases of arthemether-lumefantrine tablets which had no therapeutic effect. By means of TLC and LC, the absence of these two active ingredients was clearly demonstrated, but the presence of starch was revealed by RIM; - another case of quinine tablets that had no expected pharmacological effect was faced. The use of several combined techniques (TLC, LC-MS, NMR and RIM) allowed to detect the presence of a substance with an imidazole structure (antamoeba). antibiotics: - the case of amoxicillin powder which after reconstitution in hospital caused poisoning of the babies until death for some was investigated. The reconstitution of the suspension in the laboratory had revealed the misuse of hydrogen peroxide instead of distilled water; - we participated to a large-scale study (80 samples of amoxicillin powder) that showed 8% of overdose. The cases presented indicate that there are effectively poor quality medicines and there is need to sustain strong collaborations while reinforcing appropriate measures to protect users. [less ▲]

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See detailTowards a covering aerospray method for quantitative analyses of pharmaceutical tablets using surface-enhanced Raman chemical imaging (SER-CI)
Cailletaud, Johan ULiege; De Bleye, Charlotte ULiege; Dumont, Elodie ULiege et al

Conference (2017, September 22)

In recent years, the use of SERS-CI in pharmaceutical sciences has increased in order to study the distribution of low-dose compounds in solid dosage forms [1]. This technique allows to improve the ... [more ▼]

In recent years, the use of SERS-CI in pharmaceutical sciences has increased in order to study the distribution of low-dose compounds in solid dosage forms [1]. This technique allows to improve the sensitivity of conventional Raman microscopy and to reduce significantly the image acquisition time by exalting the signal information. However, the applications of SERS-CI in the pharmaceutical field remain limited, especially due to the difficulty of obtaining a homogeneous deposit of metallic nanoparticles on the sample surface. Generally, the covering method used on the tablet is a drop casting deposition due to its simplicity and rapidity of implementation. Despite the colloidal solution deposit is not fully controlled. The inhomogeneous covering is the result of the “coffee-ring” effect that concentrates the nanoparticles at the edges of the droplet [2]. This implies remarkable variations of the SERS analyte signal’s intensity at different places. For a more reproducible and homogeneous coating, an aerospray method using a homemade apparatus was developed (Figure 1). The device is composed with a pair of coaxial tubes, the colloidal solution is pulled through the inner tube from a syringe pump and the outer tube is connected to a source of high pressure gas. Nitrogen, used as a nebulizing gas, creates a flow of small droplets of nanoparticles that are nearly dry when they hit the sample surface. The aerospray device is easy to implement and the entire surface of the tablet is covered by the SERS substrate in a homogeneous way. By using this covering method, the potential of SERS-CI is improved and making it a suitable technique for quantitative analyses of low drug concentrations or impurities in pharmaceutical tablets. [less ▲]

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See detailTowards the development of a dual mode fluorescence/SERS dopamine aptasensor
Dumont, Elodie ULiege; De Bleye, Charlotte ULiege; Cailletaud, Johan ULiege et al

Poster (2017, September 21)

This work was dedicated to the development of a dual mode fluorescence and surface-enhanced Raman scattering (SERS) dopamine aptasensor. The preparation of the aptasensor was first optimised. Thereafter ... [more ▼]

This work was dedicated to the development of a dual mode fluorescence and surface-enhanced Raman scattering (SERS) dopamine aptasensor. The preparation of the aptasensor was first optimised. Thereafter, calibration curves were realised by means of fluorescence quenching and SERS. Finally, the specificity of both methods was tested. [less ▲]

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See detailDevelopment of SERS nanosensors for the detection of small bioactive molecules by cellular analysis in complex matrices: Application to dopamine
Dumont, Elodie ULiege; De Bleye, Charlotte ULiege; Cailletaud, Johan ULiege et al

Conference (2017, September 13)

This communication reports the different steps undertaken in order to develop a new Surface-Enhanced Raman Scattering (SERS) nanosensor for the quantification of dopamine in the culture medium of PC-12 ... [more ▼]

This communication reports the different steps undertaken in order to develop a new Surface-Enhanced Raman Scattering (SERS) nanosensor for the quantification of dopamine in the culture medium of PC-12 cells. First, the synthesis of the SERS substrate, gold nanoparticles, and its characterization. Then the development of the method with the help of a design of experiments and the demonstration of the specificity of the method over other structurally related catecholamines. And finally, the implementation of the method on the culture medium of PC-12 cells, on an HEPES buffer having served to wash the cells and on the PC-12 cells. [less ▲]

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See detailIs supercritical fluid chromatography hyphenated to massspectrometry suitable for the quality control of vitamin D3 oilyformulations?
Andri, Bertyl ULiege; Dispas, Amandine ULiege; Klinkenberg, Régis et al

in Journal of Chromatography. A (2017), 1515

Nowadays, many efforts are devoted to improve analytical methods regarding efficiency, analysis timeand greenness. In this context, Supercritical Fluid Chromatography (SFC) is often regarded as a ... [more ▼]

Nowadays, many efforts are devoted to improve analytical methods regarding efficiency, analysis timeand greenness. In this context, Supercritical Fluid Chromatography (SFC) is often regarded as a goodalternative over Normal Phase Liquid Chromatography (NPLC). Indeed, modern SFC separations arefast, efficient with suitable quantitative performances. Moreover, the hyphenation of SFC to mass spec-trometry (MS) provides additional gains in specificity and sensitivity. The present work aims at thedetermination of vitamin D3 by SFC-MS for routine Quality Control (QC) of medicines specifically. Basedon the chromatographic parameters previously defined in SFC-UV by Design of Experiments (DoE) andDesign Space methodology, the method was adapted to work under isopycnic conditions ensuring a base-line separation of the compounds. Afterwards, the response provided by the MS detector was optimizedby means of DoE methodology associated to desirability functions. Using these optimal MS parameters,quantitative performances of the SFC-MS method were challenged by means of total error approachmethod validation. The resulting accuracy profile demonstrated the full validity of the SFC-MS method. It was indeed possible to meet the specification established by the European Medicines Agency (EMA) (i.e. 95.0 − 105.0% of the API content) for a dosing range corresponding to at least 70.0-130.0% of theAPI content. These results highlight the possibility to use SFC-MS for the QC of medicine and obviouslysupport the switch to greener analytical methods. [less ▲]

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See detailGlobal regression model for moisture content determination using near-infrared spectroscopy
Clavaud, Matthieu ULiege; Roggo, Yves; Degardin, Klara et al

in European Journal of Pharmaceutics and Biopharmaceutics (2017), 119

Near-infrared (NIR) global quantitative models were evaluated for the moisture content (MC) determination of three different freeze-dried drug products. The quantitative models were based on 3822 spectra ... [more ▼]

Near-infrared (NIR) global quantitative models were evaluated for the moisture content (MC) determination of three different freeze-dried drug products. The quantitative models were based on 3822 spectra measured on two identical spectrometers to include variability. The MC, measured with the reference Karl Fischer (KF) method, were ranged from 0.05% to 4.96%. Linear and non-linear regression models using Partial Least Square (PLS), Decision Tree (DT), Bayesian Ridge Regression (Bayes-RR), K-Nearest Neighbors (KNN), and Support Vector Regression (SVR) algorithms were created and evaluated. Among them, the SVR model was retained for a global application. The Standard Error of Calibration (SEC) and the Standard Error of Prediction (SEP) were respectively 0.12% and 0.15%. This model was then evaluated in terms of total error and risk-based assessment, linearity, and accuracy. It was observed that MC can be fastly and simultaneously determined in freeze-dried pharmaceutical products thanks to a global NIR model created with different medicines. This innovative approach allows to speed up the validation time and the in-lab release analyses. [less ▲]

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See detailImpact of formulation and process parameters on near-infrared spectra: Application for water determination in biopharmaceuticals
Clavaud, Matthieu ULiege; Roggo, Yves; Allmendinger, Andrea et al

Poster (2017, June 11)

Traditionally, the water content of freeze-dried biopharmaceuticals is determined by time-consuming methods such as Karl Fischer titration. As a fast and non-destructive method, many studies demonstrated ... [more ▼]

Traditionally, the water content of freeze-dried biopharmaceuticals is determined by time-consuming methods such as Karl Fischer titration. As a fast and non-destructive method, many studies demonstrated the efficiency of Near-Infrared (NIR) spectroscopy for that purpose [1]. In this study, NIR was applied to different freeze-dried monoclonal antibody. The aim was to evaluate the robustness of a NIR model depending on formulation composition and process parameters of the lyophilization parameters, and the benefits of NIR when developing a freeze-drying cycle for a new pharmaceutical product. A full Design of experiments (DoE) was established in order to produce materials with various formulations and various process parameters. As a first step, a calibration model was created and validated. The model creation was based on 4 target lyophilized cycles which were manufactured to obtain samples with different water content concentration. Then, 20 lyophilized cycles were produced according to the DoE. Two levels of protein and sucrose concentration, and two levels of pressure / primary drying temperature and process time were investigated. Furthermore, several samples of each experiment stored at different temperature and relative humidity conditions were evaluated. Chemometrics using Principal Component Analysis (PCA) and Partial Least Squares (PLS) were used to evaluate the process variations and to determine the water content, respectively. NIR is capable to differentiate between different lyophilization process conditions, based on chemometrics. Robust calibration NIR model for water determination was generated against KF independent on lyophilization process parameters and formulation composition. NIR is suitable and robust method for drug product development of freeze-dried formulation. [less ▲]

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See detailRaman Hyperspectral Imaging: An essential tool in the pharmaceutical field
Sacre, Pierre-Yves ULiege; Netchacovitch, Lauranne ULiege; Dumont, Elodie ULiege et al

E-print/Working paper (2017)

Resulting from the combination of Raman spectroscopy and optical microscopy, Raman hyperspectral imaging has proven to be an indispensable tool in the pharmaceutical field. This article will broach a ... [more ▼]

Resulting from the combination of Raman spectroscopy and optical microscopy, Raman hyperspectral imaging has proven to be an indispensable tool in the pharmaceutical field. This article will broach a number of Raman hyperspectral imaging applications that were developed in our laboratory, in order to demonstrate the significance of the technique. [less ▲]

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See detailGlobal approach for the validation of an in-line Raman spectroscopic method to determine the API content in real-time during a hot-melt extrusion process
Netchacovitch, Lauranne ULiege; Thiry, Justine ULiege; De Bleye, Charlotte ULiege et al

in Talanta (2017), 171

Since the Food and Drug Administration (FDA) published a guidance based on the Process Analytical Technology (PAT) approach, real-time analyses during manufacturing processes are in real expansion. In ... [more ▼]

Since the Food and Drug Administration (FDA) published a guidance based on the Process Analytical Technology (PAT) approach, real-time analyses during manufacturing processes are in real expansion. In this study, in-line Raman spectroscopic analyses were performed during a Hot-Melt Extrusion (HME) process to determine the Active Pharmaceutical Ingredient (API) content in real-time. The method was validated based on a univariate and a multivariate approach and the analytical performances of the obtained models were compared. Moreover, on one hand, in-line data were correlated with the real API concentration present in the sample quantified by a previously validated off-line confocal Raman microspectroscopic method. On the other hand, in-line data were also treated in function of the concentration based on the weighing of the components in the prepared mixture. The importance of developing quantitative methods based on the use of a reference method was thus highlighted. The method was validated according to the total error approach fixing the acceptance limits at ± 15% and the α risk at ± 5%. This method reaches the requirements of the European Pharmacopeia norms for the uniformity of content of single-dose preparations. The validation proves that future results will be in the acceptance limits with a previously defined probability. Finally, the in-line validated method was compared with the off-line one to demonstrate its ability to be used in routine analyses. [less ▲]

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See detailRaman Hyperspectral Imaging: An essential tool in the pharmaceutical field
Sacre, Pierre-Yves ULiege; De Bleye, Charlotte ULiege; Netchacovitch, Lauranne ULiege et al

Conference given outside the academic context (2017)

Raman hyperspectral imaging results from the powerful combination of spatial (imaging) and spectral (Raman) information. It is increasingly used both in R&D and in the industry because it allows the ... [more ▼]

Raman hyperspectral imaging results from the powerful combination of spatial (imaging) and spectral (Raman) information. It is increasingly used both in R&D and in the industry because it allows the investigation of many characteristics of solid samples. This technique provides an accurate tool for qualitative and quantitative analysis of a pharmaceutical solid formulation. In this webinar, Assoc. Prof. Ziemons will present fundamental concepts of hyperspectral imaging data analysis and key applications in pharmaceutical and biomedical field. [less ▲]

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See detailLe fléau des faux médicaments
Marini Djang'Eing'A, Roland ULiege; Ziemons, Eric ULiege; Sacre, Pierre-Yves ULiege et al

Conference given outside the academic context (2017)

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See detailDevelopment of an analytical method for crystalline content determination in amorphous solid dispersions produced by Hot-Melt Extrusion using transmission Raman spectroscopy: A feasibility study.
Netchacovitch, Lauranne ULiege; Dumont, Elodie ULiege; Cailletaud, Johan ULiege et al

in International Journal of Pharmaceutics (2017), 530(1-2), 249-255

The development of a quantitative method determining the crystalline percentage in an amorphous solid dispersion is of great interest in the pharmaceutical field. Indeed, the crystalline Active ... [more ▼]

The development of a quantitative method determining the crystalline percentage in an amorphous solid dispersion is of great interest in the pharmaceutical field. Indeed, the crystalline Active Pharmaceutical Ingredient transformation into its amorphous state is increasingly used as it enhances the solubility and bioavailability of Biopharmaceutical Classification System class II drugs. One way to produce amorphous solid dispersions is the Hot-Melt Extrusion (HME) process. This study reported the development and the comparison of the analytical performances of two techniques, based on backscattering and transmission Raman spectroscopy, determining the crystalline remaining content in amorphous solid dispersions produced by HME. Principal Component Analysis (PCA) and Partial Least Squares (PLS) regression were performed on preprocessed data and tended towards the same conclusions: for the backscattering Raman results, the use of the DuoScan™ mode improved the PCA and PLS results, due to a larger analyzed sampling volume. For the transmission Raman results, the determination of low crystalline percentages was possible and the best regression model was obtained using this technique. Indeed, the latter acquired spectra through the whole sample volume, in contrast with the previous surface analyses performed using the backscattering mode. This study consequently highlighted the importance of the analyzed sampling volume. [less ▲]

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See detailOptimization and validation of a fast Supercritical Fluid Chromatography method for the quantitative determination of vitamin D3 and its related impurities.
Andri, Bertyl ULiege; Lebrun, Pierre ULiege; Dispas, Amandine ULiege et al

in Journal of Chromatography. A (2017)

In the uprising context of green analytical chemistry, Supercritical Fluid Chromatography (SFC) is often suggested as an alternative to Normal Phase Liquid Chromatography. Indeed, SFC provides fast ... [more ▼]

In the uprising context of green analytical chemistry, Supercritical Fluid Chromatography (SFC) is often suggested as an alternative to Normal Phase Liquid Chromatography. Indeed, SFC provides fast, efficient and green separations. In this report, the quantitative performances of SFC were challenged on a real-life case study: the Quality Control (QC) of vitamin D3. A rapid and green SFC method was optimized thanks to the Design of Experiments–Design Space (DoE–DS) methodology. It provided robust and high quality separation of the compounds within a 2 min timeframe, using a gradient of ethanol as co-solvent of the carbon dioxide. The analytical method was fully validated according to the total error approach, demon- strating the compliance of the method to the specifications of U.S. Pharmacopeia (USP: 97.0–103.0%) and European Pharmacopeia (EP: 97.0–102.0%) for an interval of [50–150%] of the target concentration. In order to allow quantification of impurities using vitamin D3 as an external standard in SFC-UV, correction factors were determined and verified during method validation. Thus, accurate quantification of impu- rities was demonstrated at the specified levels (0.1 and 1.0% of the main compound) for a 70.0–130.0% dosing range. This work demonstrates the validity of an SFC method for the QC of vitamin D3 raw material and its application to real samples. Therefore, it supports the switch to a greener and faster separative technique as an alternative to NPLC in the pharmaceutical industry. [less ▲]

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See detailContinuous Production of Itraconazole-based Solid Dispersions by Hot Melt Extrusion: Preformulation, Optimization and Design Space Determination.
Thiry, Justine ULiege; Lebrun, Pierre; Vinassa, Chloé et al

in International Journal of Pharmaceutics (2016), 515(1-2), 114-124

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See detailSFC: A green alternative for quantitative analysis in the pharmaceutical field?
Dispas, Amandine ULiege; Lebrun, Pierre ULiege; Ziemons, Eric ULiege et al

Conference (2016, October 07)

Detailed reference viewed: 37 (6 ULiège)