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8. Fate of Tableted Freeze-Dried siRNA Lipoplexes in Gastrointestinal Environment

Author

Asad Ur Rehman, Virginie Busignies, Marcela Coelho Silva Ribeiro, Nayara Almeida Lage, Pierre Tchoreloff, Virginie Escriou, and Christine Charrueau

Subjects
oral delivery, RNA interference, solid dosage form, gel electrophoresis, nanocarriers, Pharmacy and materia medica, RS1-441
Abstract

The incorporation of siRNA into nanocarriers is mandatory to facilitate its intracellular delivery, as siRNA itself cannot enter cells. However, the incorporation of these nanocarriers into oral, solid dosage forms and their fate in the gastrointestinal environment is yet to be explored. In the present work, the fate of, (i) naked siRNA, (ii) freshly prepared siRNA lipoplexes, and (iii) tableted siRNA lipoplexes, in simulated gastric and intestinal fluids was studied. The siRNA, either released from or protected within the lipoplexes, was quantified by gel electrophoresis and siRNA efficacy was assessed in cell transfection. The freshly prepared lipoplexes kept their siRNA load and transfection efficiency totally preserved during 1 h of incubation in simulated gastric fluid at 37 °C. However, in simulated intestinal fluid, despite no release of siRNA from lipoplexes after 6 h of incubation, gene silencing efficacy was dramatically decreased even after 1 h of exposure. The lipoplexes obtained from tablets efficiently protected siRNA in simulated gastric fluid, thus preserving the gene silencing efficacy, whereas their incubation in simulated intestinal fluid resulted in a marked siRNA release and decreased gene silencing efficacy. These results provided a detailed explanation for understanding the fate of siRNA in gastrointestinal conditions, when simply loaded in lipoplexes or formulated in the form of tablets.

Published
2021
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21. Mechanistic approach to stability studies as a tool for the optimization and development of new products based on L. rhamnosus Lcr35® in compliance with current regulations.

Author

Claudia Muller, Virginie Busignies, Vincent Mazel, Christiane Forestier, Adrien Nivoliez, and Pierre Tchoreloff

Subjects
Medicine, Science
Abstract

Probiotics are of great current interest in the pharmaceutical industry because of their multiple effects on human health. To beneficially affect the host, an adequate dosage of the probiotic bacteria in the product must be guaranteed from the time of manufacturing to expiration date. Stability test guidelines as laid down by the ICH-Q1A stipulate a minimum testing period of 12 months. The challenge for producers is to reduce this time. In this paper, a mechanistic approach using the Arrhenius model is proposed to predict stability. Applied for the first time to laboratory and industrial probiotic powders, the model was able to provide a reliable mathematical representation of the effects of temperature on bacterial death (R(2)>0.9). The destruction rate (k) was determined according to the manufacturing process, strain and storage conditions. The marketed product demonstrated a better stability (k = 0.08 months(-1)) than the laboratory sample (k = 0.80 months(-1)). With industrial batches, k obtained at 6 months of studies was comparable to that obtained at 12 months, evidence of the model's robustness. In addition, predicted values at 12 months were greatly similar (±30%) to those obtained by real-time assessing the model's reliability. This method could be an interesting approach to predict the probiotic stability and could reduce to 6 months the length of stability studies as against 12 (ICH guideline) or 24 months (expiration date).

Published
2013
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31. Impact des traitements physicochimiques sur la clarte des hydrogels de trois amidons natifs de Cote d’Ivoire. Impact of physico chemical treatments on clarity of hydrogels from tree native starches from Cote d’Ivoire

Author

Dally, LI, Lia, GJ, N'Guessan, AA, Koffi, AA, and Tchoreloff, P

Subjects
Hydrogels, clarté, tubercules, paramètres physicochimiques
Abstract

Justification : Les hydrogels ou excipients hydratés sont obtenus par transformation hydro thermiques des amidons ou autres polymères organiques et minéraux et ont de nombreuses applications en pharmacie. Dans le but de valoriser nos ressources locales naturelles pour un usage pharmaceutique et notamment dans la mise au point d’excipients pour des formes pharmaceutiques liquides et semi solides, nous avons utilisé les tubercules de trois plantes amylacées : l’Igname (Dioscorea cayenensis rotundata), le Taro (Xanthosoma sagitiffolium) et la Patate douce (Ipomea batatas). L’objectif est d’évaluer l’influence de quelques facteurs physicochimiques sur la clarté des hydrogels obtenus à partir de ces amidons qui sont connus pour altérer fortement la structure des hydrogels.Méthodes : La préparation est réalisée selon la méthode décrite par PINGNAULT utilisant 4% (P/P) d’amidon en base sèche.Sur les gels obtenu ont été déterminés successivement l’influence de la conservation au froid (4°C) par la méthode de CRAIG, de la longueur d’onde entre 400 et 700 nm, de la concentration en amidon sur des échantillons, des sucres selon la méthode décrite par BELLO-PEREZ et PAREDEZLOPEZ et celle du pH de formation (2,4,5,neutre, 9 et 10,3).Résultats : La clarté des hydrogels d’amidon est très variable. Elle est de 26,5 à 41,5% pour Dioscorea cayenensis-rotundata, 21,8 à 25,2% pour Xanthosoma sagitiffolium et de 26,1 à 26,3% pour Ipomea batatas, avec une moyenne globale entre 25 et 34% de transmittance. Stockés à 4°C la clarté chute brutalement au cours de la première semaine. Les amidons sont tous sensibles au pH acide .La viscosité à pH3 baisse de 33% en moyenne pour les ignames, 28% pour le taro et 14% pour la patate douce.Conclusion : Les amidons locaux pourraient servir d’épaississant dans certaines formes liquides et de bons stabilisants pour les formes pâteuses.Mots clés : Hydrogels, clarté, tubercules, paramètres physicochimiques.ABSTRACTJustification: The hydrogels or hydrated excipients are obtained by hydrothermal conversion of starches or other organic polymers and minerals and have many applications in pharmacy. In order to enhance our natural local resources for pharmaceutical use and in particular the development of excipients for liquid and semisolid dosage forms, we used three tubers of starchy plants: Yam (Dioscorea rotundata cayenensis), Taro (Xanthosoma sagitiffolium) and sweet potato (Ipomoea batatas). The objective is to evaluate the influence of some physicochemical factors on the clarity of the hydrogels obtained from these starches that are known to greatly alter the structure of hydrogels.Methods: The preparation is carried out according to the method described by PINGNAULT using 4% (w/w) of starch dry basis. On the gels obtained were determined successively the influence of the cold storage (4 °C) by CRAIG method, the wavelength between 400 and 700 nm, the starch concentration on samples, sugars as described by BELLO PEREZ-and-Paredez LOPEZ and that of the formation of pH (2, 4, 5, neutral, 9 and 10.3).Results: The clarity of starch hydrogels is highly variable. It is 26.5 to 41.5% for Dioscorea cayenensis rotundata, 21.8 to 25.2% for Xanthosoma sagitiffolium and 26.1 to 26.3% for Ipomoea batatas, with an overall average between 25 and 34% of transmittance. Stored at 4° C clarity drops sharply during the first week. Starches are sensitive to acidic pH .The viscosity at pH 3 down 33% on average for yams, taro for 28% and 14% for sweet potato.Conclusion: Local starches could be used as a thickener in some liquid forms and good stabilizers for paste forms.Keywords: Hydrogels, clarity, tubers, physicochemical parameters.

Published
2016

32. Compression of Vectors for Small Interfering RNAs Delivery: Toward Oral Administration of siRNA Lipoplexes in Tablet Forms

Author

Busignies, Virginie, Arruda, Danielle Campiol, Charrueau, Christine, Ribeiro, Marcela Coelho Silva, Lachagès, Anne-Marie, Malachias, Angelo, Finet, Stéphanie, Rehman, Asad Ur, Bigey, Pascal, Tchoreloff, Pierre, and Escriou, Virginie

Abstract

Currently, most nonviral nucleic acid vectors are in the form of colloidal suspensions administered primarily parenterally. This type of formulation and the mode of administration impose strong constraints such as the size of the administered vectors or the production of sterile preparations. The tablet form provides access to easy oral administration, well accepted by patients; As regards nucleic acid vectors, a dry form represents an advance in terms of stability. Using an optimized lipid-based small interfering RNA-delivery system, we studied the tabletability of a liquid suspension of these vectors. We optimized the conditions of freeze-drying by choosing excipients and process, allowing for the conservation of both the gene-silencing efficacy of the formulated siRNAs and the supramolecular structure of the lipid particulate system. Gene-silencing efficacy was assayed on luciferase-expressing cells and the structure of the siRNA vector in freeze-dried and tablet forms was examined using small-angle X-ray scattering (SAXS) synchrotron radiation. The freeze-dried powders were then mixed with excipients necessary for the good progress of the compression by allowing for a regular supply of the matrix and the reduction of friction. The compression was carried out using a rotary press simulator that allows for complete monitoring of the compression conditions. After compression, formulated siRNAs retained more than 60% of their gene-silencing efficacy. Within the tablets, a specific SAXS signal was detectable and the lamellar and cubic phases of the initial liquid suspension were restored after resuspension of siRNA vectors by disintegration of the tablets. These results show that the bilayer lipid structures of the particles were preserved despite the mechanical constraints imposed by the compression. If such a result could be expected after the freeze-drying step, it was never shown, to our knowledge, that siRNA-delivery systems could retain their efficacy and structure after mechanical stress such as compression. This opens promising perspectives to oral administration of siRNA as an alternative to parenteral administration.

Published
2020
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34. Mechanical properties of compacts made with binary mixtures of pharmaceutical excipients of three different kinds

Author

Busignies, V., Evesque, P., Porion, P., Leclerc, B., Tchoreloff, P., Groupe d'Etudes sur la Fonctionnalisation des Solides Divisés (GEFSOD), Université de Limoges (UNILIM), Laboratoire de mécanique des sols, structures et matériaux (MSSMat), CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche sur la Matière Divisée (CRMD), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Matériaux et produits de santé - Faculté de Pharmacie, and Université Paris-Sud - Paris 11 (UP11)

Subjects
[SPI.MECA.MSMECA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Materials and structures in mechanics [physics.class-ph], [PHYS.MECA.MSMECA]Physics [physics]/Mechanics [physics]/Materials and structures in mechanics [physics.class-ph]
Published
2009

35. Porous Structure of Pharmaceutical Tablets Studied Using PGSTE-NMR Technique

Author

Porion, P., Tchoreloff, P., Busignies, V., Leclerc, B., Evesque, P., Centre de Recherche sur la Matière Divisée (CRMD), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Matériaux et produits de santé - Faculté de Pharmacie, Université Paris-Sud - Paris 11 (UP11), Groupe d'Etudes sur la Fonctionnalisation des Solides Divisés (GEFSOD), Université de Limoges (UNILIM), Laboratoire de mécanique des sols, structures et matériaux (MSSMat), and CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.MECA.MSMECA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Materials and structures in mechanics [physics.class-ph], [PHYS.MECA.MSMECA]Physics [physics]/Mechanics [physics]/Materials and structures in mechanics [physics.class-ph]
Published
2009

36. Porous-Structure of Pharmaceutical Tablets Studied Using PGSTE NMR technique

Author

Poirion, P., Tchoreloff, P., Busignies, V., Leclerc, B., Evesque, P., Matériaux et produits de santé - Faculté de Pharmacie, Université Paris-Sud - Paris 11 (UP11), Laboratoire de mécanique des sols, structures et matériaux (MSSMat), and CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.MECA.MSMECA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Materials and structures in mechanics [physics.class-ph], [PHYS.MECA.MSMECA]Physics [physics]/Mechanics [physics]/Materials and structures in mechanics [physics.class-ph]
Published
2009

37. Can percolation model describe the evolution of mechanical properties of compacts of binary systems

Author

Evesque, P., Busignies, V., Tchoreloff, P., Leclerc, B., Porion, P., Laboratoire de mécanique des sols, structures et matériaux (MSSMat), CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Groupe d'Etudes sur la Fonctionnalisation des Solides Divisés (GEFSOD), Université de Limoges (UNILIM), Matériaux et produits de santé - Faculté de Pharmacie, Université Paris-Sud - Paris 11 (UP11), Centre de Recherche sur la Matière Divisée (CRMD), and Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)

Subjects
[SPI.MECA.MSMECA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Materials and structures in mechanics [physics.class-ph], [PHYS.MECA.MSMECA]Physics [physics]/Mechanics [physics]/Materials and structures in mechanics [physics.class-ph]
Published
2009

38. New application of PGSE-NMR technique to characterize the porous structure of pharmaceutical tablets

Author

Busignies, V., Poirion, P., Leclerc, B., Evesque, P., Tchoreloff, P., Groupe d'Etudes sur la Fonctionnalisation des Solides Divisés (GEFSOD), Université de Limoges (UNILIM), Laboratoire de mécanique des sols, structures et matériaux (MSSMat), CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Matériaux et produits de santé - Faculté de Pharmacie, Université Paris-Sud - Paris 11 (UP11), and Verrouil, Francoise

Subjects
[SPI.MECA.MSMECA] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Materials and structures in mechanics [physics.class-ph], [PHYS.MECA.MSMECA] Physics [physics]/Mechanics [physics]/Materials and structures in mechanics [physics.class-ph], [SPI.MECA.MSMECA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Materials and structures in mechanics [physics.class-ph], [PHYS.MECA.MSMECA]Physics [physics]/Mechanics [physics]/Materials and structures in mechanics [physics.class-ph]
Published
2008

39. Poudres, granulés et comprimés dans Pharmacie Galénique

Author

Busignies, V., Chulia, Dominique, Choisnard, L., de Challemaison, R., Geze, A., Stainmesse, S., Siepmann, J., Tchoreloff, P., Viana, Marylène, Wehrle, P., Wouessidjewe, D., Groupe d'Etudes sur la Fonctionnalisation des Solides Divisés (GEFSOD), Université de Limoges (UNILIM), Département de pharmacochimie moléculaire (DPM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Chaire des Techniques pharmaceutiques, Conservatoire National des Arts et Métiers [CNAM] (CNAM), Laboratoire de pharmacotechnie Industrielle - EJ 2401, Université de Lille, Droit et Santé, Matériaux et produits de santé - Faculté de Pharmacie, Université Paris-Sud - Paris 11 (UP11), Laboratoire de Pharmacie galénique et de pharmacotechnie, Faculté de Pharmacie, and Decout, Jean Luc

Subjects
[SDV.SP] Life Sciences [q-bio]/Pharmaceutical sciences, [SDV.SP]Life Sciences [q-bio]/Pharmaceutical sciences
Published
2007

40. Co-broyage de principes actifs pharmaceutiques pour ameliorer leur biodisponibilite

Author

Oudet, L., Tchoreloff, P., Guy Couarraze, Michel Baron, Dodds, John A., alain chamayou, Pakkanen, S., Larsen, J. O., Nachon, G., Poudres et procédés - Ecole des Mines Albi-Carmaux, IMT École nationale supérieure des Mines d'Albi-Carmaux (IMT Mines Albi), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), IMT École nationale supérieure des Mines d'Albi-Carmaux ( IMT Mines Albi ), and IMT Mines Albi, IMT Mines Albi

Subjects
[SPI]Engineering Sciences [physics], [SPI] Engineering Sciences [physics], [ SPI ] Engineering Sciences [physics], ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
1998

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