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Lombardo R, Ruponen M, Rautio J, Ghelardini C, Di Cesare Mannelli L, Calosi L, Bani D, Lampinen R, Kanninen KM, Koivisto AM, Penttilä E, Löppönen H, Pignatello R. Development of Lyophilised Eudragit ® Retard Nanoparticles for the Sustained Release of Clozapine via Intranasal Administration. Pharmaceutics 2023; 15:pharmaceutics15051554. [PMID: 37242796 DOI: 10.3390/pharmaceutics15051554] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/12/2023] [Accepted: 05/17/2023] [Indexed: 05/28/2023] Open
Abstract
Clozapine (CZP) is the only effective drug in schizophrenia resistant to typical antipsychotics. However, existing dosage forms (oral or orodispersible tablets, suspensions or intramuscular injection) show challenging limitations. After oral administration, CZP has low bioavailability due to a large first-pass effect, while the i.m. route is often painful, with low patient compliance and requiring specialised personnel. Moreover, CZP has a very low aqueous solubility. This study proposes the intranasal route as an alternative route of administration for CZP, through its encapsulation in polymeric nanoparticles (NPs) based on Eudragit® RS100 and RL100 copolymers. Slow-release polymeric NPs with dimensions around 400-500 nm were formulated to reside and release CZP in the nasal cavity, where it can be absorbed through the nasal mucosa and reach the systemic circulation. CZP-EUD-NPs showed a controlled release of CZP for up to 8 h. Furthermore, to reduce mucociliary clearance and increase the residence time of NPs in the nasal cavity to improve drug bioavailability, mucoadhesive NPs were formulated. This study shows that the NPs already exhibited strong electrostatic interactions with mucin at time zero due to the presence of the positive charge of the used copolymers. Furthermore, to improve the solubility, diffusion and adsorption of CZPs and the storage stability of the formulation, it was lyophilised using 5% (w/v) HP-β-CD as a cryoprotectant. It ensured the preservation of the NPs' size, PDI and charge upon reconstitution. Moreover, physicochemical characterisation studies of solid-state NPs were performed. Finally, toxicity studies were performed in vitro on MDCKII cells and primary human olfactory mucosa cells and in vivo on the nasal mucosa of CD-1 mice. The latter showed non-toxicity of B-EUD-NPs and mild CZP-EUD-NP-induced tissue abnormalities.
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Affiliation(s)
- Rosamaria Lombardo
- Laboratory of Drug Delivery Technology, Department of Drug and Health Sciences, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Marika Ruponen
- School of Pharmacy, University of Eastern Finland, Yliopistonranta 1C, 70210 Kuopio, Finland
| | - Jarkko Rautio
- School of Pharmacy, University of Eastern Finland, Yliopistonranta 1C, 70210 Kuopio, Finland
| | - Carla Ghelardini
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA)-Pharmacology and Toxicology Section, University of Florence, 50139 Florence, Italy
| | - Lorenzo Di Cesare Mannelli
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA)-Pharmacology and Toxicology Section, University of Florence, 50139 Florence, Italy
| | - Laura Calosi
- Platform of Imaging, Department of Experimental & Clinical Medicine, University of Florence, 50139 Florence, Italy
| | - Daniele Bani
- Platform of Imaging, Department of Experimental & Clinical Medicine, University of Florence, 50139 Florence, Italy
| | - Riikka Lampinen
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, 70210 Kuopio, Finland
| | - Katja M Kanninen
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, 70210 Kuopio, Finland
| | - Anne M Koivisto
- Brain Research Unit, Department of Neurology, School of Medicine, University of Eastern Finland, 70200 Kuopio, Finland
- Department of Neurology, Neuro Centre, Kuopio University Hospital, 70210 Kuopio, Finland
- Department of Neurology and Geriatrics, Helsinki University Hospital and Neurosciences, Faculty of Medcine, University of Helsinki, 00290 Helsinki, Finland
| | - Elina Penttilä
- Department of Otorhinolaryngology, University of Eastern Finland, Kuopio University Hospital, 70210 Kuopio, Finland
| | - Heikki Löppönen
- Department of Otorhinolaryngology, University of Eastern Finland, Kuopio University Hospital, 70210 Kuopio, Finland
| | - Rosario Pignatello
- Laboratory of Drug Delivery Technology, Department of Drug and Health Sciences, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
- NANOMED-Research Centre on Nanomedicine and Pharmaceutical Nanotechnology, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
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Encapsulation of Large-Size Plasmids in PLGA Nanoparticles for Gene Editing: Comparison of Three Different Synthesis Methods. NANOMATERIALS 2021; 11:nano11102723. [PMID: 34685164 PMCID: PMC8541650 DOI: 10.3390/nano11102723] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 10/07/2021] [Accepted: 10/08/2021] [Indexed: 12/12/2022]
Abstract
The development of new gene-editing technologies has fostered the need for efficient and safe vectors capable of encapsulating large nucleic acids. In this work we evaluate the synthesis of large-size plasmid-loaded PLGA nanoparticles by double emulsion (considering batch ultrasound and microfluidics-assisted methodologies) and magnetic stirring-based nanoprecipitation synthesis methods. For this purpose, we characterized the nanoparticles and compared the results between the different synthesis processes in terms of encapsulation efficiency, morphology, particle size, polydispersity, zeta potential and structural integrity of loaded pDNA. Our results demonstrate particular sensibility of large pDNA for shear and mechanical stress degradation during double emulsion, the nanoprecipitation method being the only one that preserved plasmid integrity. However, plasmid-loaded PLGA nanoparticles synthesized by nanoprecipitation did not show cell expression in vitro, possibly due to the slow release profile observed in our experimental conditions. Strong electrostatic interactions between the large plasmid and the cationic PLGA used for this synthesis may underlie this release kinetics. Overall, none of the methods evaluated satisfied all the requirements for an efficient non-viral vector when applied to large-size plasmid encapsulation. Further optimization or alternative synthesis methods are thus in current need to adapt PLGA nanoparticles as delivery vectors for gene editing therapeutic technologies.
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Curcio C, Greco AS, Rizzo S, Saitta L, Musumeci T, Ruozi B, Pignatello R. Development, Optimization and Characterization of Eudraguard ®-based Microparticles for Colon Delivery. Pharmaceuticals (Basel) 2020; 13:ph13060131. [PMID: 32599861 PMCID: PMC7344638 DOI: 10.3390/ph13060131] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/12/2020] [Accepted: 06/15/2020] [Indexed: 01/16/2023] Open
Abstract
Development of pH-dependent systems for colon delivery of natural active ingredients is an attractive area of research in the field of nutraceutical products. This study was focused on Eudraguard® resins, that are methacrylate copolymers approved as “food grade” by European Commission and useful for the production of food supplements. In particular, Eudraguard® Biotic (EUG-B), characterized by a pH-dependent solubility and Eudraguard® Control (EUG-C), whose chemical properties support a prolonged release of the encapsulated compounds, were tested. To obtain EUG microparticles, different preparation techniques were tested, in order to optimize the preparation method and observe the effect upon drug encapsulation and specific colonic release. Unloaded microparticles were initially produced to evaluate the influence of polymer characteristics on the formulation process; subsequently microparticles loaded with quercetin (QUE) as a low solubility model drug were prepared. The characterization of microparticles in the solid-state (FT-IR spectroscopy, differential scanning calorimetry and X-ray diffractometry) indicated that QUE was uniformly dispersed in a non-crystalline state in the polymeric network, without strong signs of chemical interactions. Finally, to assess the ability of EUG-C and EUG-B to control the drug release in the gastric environment, and to allow an increased release at a colonic level, suitable in vitro release tests were carried out by simulating the pH variations along the gastro-intestinal tract. Among the evaluated preparation methods, those in which an aqueous phase was not present, and in particular the emulsion-solvent evaporation method produced the best microparticle systems. The in vitro tests showed a limited drug release at a gastric level and a good specific colon release.
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Affiliation(s)
- Claudia Curcio
- Department of Drug Sciences, Section of Pharmaceutical Technology, University of Catania, 95125 Catania, Italy; (C.C.); (A.S.G.); (S.R.); (T.M.)
| | - Antonio S. Greco
- Department of Drug Sciences, Section of Pharmaceutical Technology, University of Catania, 95125 Catania, Italy; (C.C.); (A.S.G.); (S.R.); (T.M.)
| | - Salvatore Rizzo
- Department of Drug Sciences, Section of Pharmaceutical Technology, University of Catania, 95125 Catania, Italy; (C.C.); (A.S.G.); (S.R.); (T.M.)
| | - Lorena Saitta
- Department of Civil Engineering and Architecture (DICAR), University of Catania, 95125 Catania, Italy;
| | - Teresa Musumeci
- Department of Drug Sciences, Section of Pharmaceutical Technology, University of Catania, 95125 Catania, Italy; (C.C.); (A.S.G.); (S.R.); (T.M.)
| | - Barbara Ruozi
- Department of Life Sciences, University of Modena and Reggio Emilia, 41100 Modena, Italy;
| | - Rosario Pignatello
- Department of Drug Sciences, Section of Pharmaceutical Technology, University of Catania, 95125 Catania, Italy; (C.C.); (A.S.G.); (S.R.); (T.M.)
- Correspondence:
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Steering the Clinical Translation of Delivery Systems for Drugs and Health Products. Pharmaceutics 2020; 12:pharmaceutics12040350. [PMID: 32294939 PMCID: PMC7238002 DOI: 10.3390/pharmaceutics12040350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 03/17/2020] [Indexed: 11/21/2022] Open
Abstract
Besides the feasibility for industrial scale-up, accelerating the translation from bench to bedside of new technological strategies for controlled delivery and targeting of drugs and other actives relevant for health management, such as medical devices and nutraceuticals, would benefit from an even earlier evaluation in pre-clinical models and clinical settings. At the same time, translational medicine also performs in the opposite direction, incorporating clinical needs and observations into scientific hypotheses and innovative technological proposals. With these aims, the sessions proposed for the 2019 CRS Italy Chapter Workshop will introduce the experience of Italian and worldwide researchers on how to foster the actual work in controlled release and drug delivery towards a reliable pre-clinical and clinical assessment.
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Adibkia K, Selselehjonban S, Emami S, Osouli-Bostanabad K, Barzegar-Jalali M. Electrosprayed polymeric nanobeads and nanofibers of modafinil: preparation, characterization, and drug release studies. ACTA ACUST UNITED AC 2019; 9:179-188. [PMID: 31508333 PMCID: PMC6726752 DOI: 10.15171/bi.2019.22] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 11/20/2018] [Accepted: 11/27/2018] [Indexed: 12/03/2022]
Abstract
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Introduction: Modafinil (MDF) is used orally for the treatment of attention-deficit/hyperactivity disorder and narcolepsy. It holds low solubility and high permeability; therefore, improving its dissolution properties by preparing nanoformulations can be a promising approach to enhance its oral absorption. Our aims were to prepare and characterize MDF-Eudragit® RS100 (MDF-ERS) nanoparticles by electrospray technique.
Methods: Electrosprayed nanoparticles were fabricated by varying MDF to ERS ratios and concentrations. The formulations were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and Fourier-transform infrared spectroscopy (FTIR). Release studies were performed on nanoparticles, physical mixtures, and raw MDF. The release data were fitted to different models to understand the mechanism of the drug release.
Results: Electrospraying of MDF and ERS solution resulted in the preparation of nonobeads or nanofibers, and the particulate characteristics of the obtained products were largely controlled by the polymer amount in the solution. PXRD and thermal analyses showed that MDF was an amorphous phase in the structures of nanoparticles. Using FTIR, no interaction was observed between MDF and ERS in nanoparticles. Nanoparticles showed biphasic release profiles and the order of dissolution rates was: nanofibers>MDF>nanobeads. The well-fitted model was Weibull model, indicating a Fickian diffusion as the main mechanism of release.
Conclusion: The results suggest that by optimization of variables such as solution concentration of MDF-ERS nanofibers and nanobeads with higher dissolution rates can be made by electrospray. Electrospray deposition as a simple, continuous, and surfactant free method is an excellent choice for preparation of drug loaded polymeric nanoparticles.
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Affiliation(s)
- Khosro Adibkia
- Research Center for Pharmaceutical Nanotechnology and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Sevil Selselehjonban
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.,Drug Applied Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Shahram Emami
- Department of Pharmaceutics, School of Pharmacy, Urmia University of Medical Sciences, Urmia, Iran
| | - Karim Osouli-Bostanabad
- Research Center for Pharmaceutical Nanotechnology and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.,Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Barzegar-Jalali
- Drug Applied Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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Pignatello R, Pecora TMG, Cutuli GG, Catalfo A, De Guidi G, Ruozi B, Tosi G, Cianciolo S, Musumeci T. Antioxidant activity and photostability assessment of trans-resveratrol acrylate microspheres. Pharm Dev Technol 2018; 24:222-234. [PMID: 29565215 DOI: 10.1080/10837450.2018.1455697] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Trans-resveratrol (RSV) was microencapsulated in Eudragit® RS100 and RL100 resin blends. Lyophilized microspheres were characterized in the solid state for their micromeritic properties and drug loading. FT-IR, PXRD, and DSC analyzes suggested that RSV formed an intimate microcrystalline dispersion within the polymer network, also confirmed by SEM analysis. This produced a reduced degradation of RSV after storage at 40 °C, compared to the neat drug, and a protection of the drug from UV light-induced trans-cis isomerization (60% intact drug was found after 60 s irradiation at 350 nm, compared to 37% for the pure drug). Solubility and in vitro dissolution studies indicated that microencapsulation did not improve the dissolution pattern of RSV in simulated gastric and intestinal aqueous fluids. Evaluation of the in vitro antioxidant activity showed that, compared to the neat drug in aqueous solution, RSV loaded in the microspheres retained for a longer time, up to 22 days of incubation, the initial ORAC capacity. The present study thus demonstrated that Eudragit® Retard resins can be used to easily produce micro-sized solid dispersions with RSV, for potential oral administration, contributing to ameliorate the physico-chemical stability and antioxidant activity of this compound.
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Affiliation(s)
- Rosario Pignatello
- a Section of Pharmaceutical Technology, Department of Drug Sciences , University of Catania , Catania , Italy
| | - Tiziana M G Pecora
- b Department of Health Sciences , University "Magna Graecia" , Catanzaro , Italy
| | - Giuseppa G Cutuli
- a Section of Pharmaceutical Technology, Department of Drug Sciences , University of Catania , Catania , Italy
| | - Alfio Catalfo
- c Department of Chemical Sciences , University of Catania , Catania , Italy
| | - Guido De Guidi
- c Department of Chemical Sciences , University of Catania , Catania , Italy.,d Centro di ricerca per l'analisi, il monitoraggio e le metodologie di minimizzazione del rischio ambientale (CRAM3RA) , Università di Catania , Catania, Italy
| | - Barbara Ruozi
- e Nanotech Lab of TeFarTI group, Department of Life Sciences , University of Modena and Reggio Emilia , Modena , Italy
| | - Giovanni Tosi
- e Nanotech Lab of TeFarTI group, Department of Life Sciences , University of Modena and Reggio Emilia , Modena , Italy
| | - Simona Cianciolo
- a Section of Pharmaceutical Technology, Department of Drug Sciences , University of Catania , Catania , Italy
| | - Teresa Musumeci
- a Section of Pharmaceutical Technology, Department of Drug Sciences , University of Catania , Catania , Italy
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Jafari-Aghdam N, Adibkia K, Payab S, Barzegar-Jalali M, Parvizpur A, Mohammadi G, Sabzevari A. Methylprednisolone acetate–Eudragit®RS100 electrospuns: Preparation and physicochemical characterization. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2014; 44:497-503. [DOI: 10.3109/21691401.2014.965309] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Jelvehgari M, Barghi L, Barghi F. Preparation of Chlorpheniramine Maleate-loaded Alginate/Chitosan Particulate Systems by the Ionic Gelation Method for Taste Masking. Jundishapur J Nat Pharm Prod 2014; 9:39-48. [PMID: 24644438 PMCID: PMC3957142 DOI: 10.17795/jjnpp-12530] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 10/06/2013] [Accepted: 10/22/2013] [Indexed: 11/25/2022] Open
Abstract
Background: Chlorpheniramine maleate (CM) is widely used as an antihistaminic drug but it is very bitter and as yet no mouth dissolving/disintegrating taste-masked preparation that might be useful for pediatric and geriatric patients is available in the market. Objectives: The purpose of this research was to mask the bitter taste of CM by formulating microspheres of the taste-masked drug. Materials and Methods: This work was done to develop alginate/chitosan particles prepared by ionic gelation (Ca2+ and Al3+) for the CM release. The effect of different chitosan and Ca2+ concentrations on taste masking and the characteristics of the microspheres were investigated. Ca2+ and Al3+ alginates microspheres of CM were prepared using cross-linked insoluble complexes that precipitate, incorporating the drug. Formulations were characterized for particle size and shape, entrapment efficiency, fourier transform spectroscopy (FTIR), x-ray diffraction (XRD), and differential scanning calorimetry (DSC), bitter taste threshold and in vitro drug release in simulated gastrointestinal fluids. Results: FTIR, XRD and DSC demonstrated unstable characters of CM in the drug-loaded microspheres and revealed an amorphous form. Also, the peak of alginate microparticles (Ca2+ and Al3+ ions) in all formulations remained the same, with low intensity of spectrum. The results of DSC, X-ray diffraction and FTIR showed the presence of several CM chemical interactions with alginate and ions (Ca2+ and Al3+). The microsphere formulations showed desirable drug entrapment efficiencies (62.2-94.2%). Calcium/aluminum alginate retarded the release of CM at low pH = 1.2 and released the drug from microspheres slowly at pH = 6.8, simulating intestine pH. The drug release duration and the release kinetics were dependent on the nature of the polymers, the cation concentrations, and valences (Ca2+ and Al3+). The drug release rate was decreased by an increase in chitosan and cation concentrations. Conclusions: The results of the present study indicated that oral preparation of CM with an acceptable taste is feasible.
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Affiliation(s)
- Mitra Jelvehgari
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, IR Iran ; Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, IR Iran
| | - Leila Barghi
- Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, IR Iran
| | - Farhad Barghi
- Student Research committee, Tabriz University of Medical Sciences, Tabriz, IR Iran
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Shah S, Madan S, Agrawal SS. Formulation and evaluation of microsphere based oro dispersible tablets of itopride hcl. Daru 2012; 20:24. [PMID: 23351176 PMCID: PMC3555840 DOI: 10.1186/2008-2231-20-24] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 07/10/2012] [Indexed: 11/17/2022] Open
Abstract
UNLABELLED BACKGROUND The purpose of the present work is to mask the intensely bitter taste of Itopride HCl and to formulate an Oro dispersible tablet (ODT) of the taste-masked drug by incorporation of microspheres in the tablets for use in specific populations viz. pediatrics, geriatrics and patients experiencing difficulty in swallowing. METHODS With this objective in mind, microspheres loaded with Itopride HCl were prepared by solvent evaporation method using acetone as solvent for pH-sensitive polymer, Eudragit EPO and light liquid paraffin as the encapsulating medium. The prepared microspheres were characterized with regard to yield, drug content, flow properties, particle size and size distribution, surface features, in vitro drug release and taste. The ODTs so prepared from these microspheres were evaluated for hardness, thickness, weight variation, friability, disintegration time, drug content, wetting time, water absorption ratio, moisture uptake, in vitro dispersion, in vitro disintegration, in vitro drug release and stability. RESULTS The average size of microspheres was found to be satisfactory in terms of the size and size distribution. Microspheres prepared were of a regular spherical shape. Comparison of the dissolution profiles of microspheres in different pH media showed that microspheres having drug: polymer ratio of 1:2 produced a retarding effect in simulated salivary fluid (pH 6.8) and were further used for formulation into ODTs after addition of suitable amounts of excipients such as superdisintegrant, diluent, sweetener and flavor of directly compressible grade. CONCLUSIONS Effective taste-masking was achieved for Itopride HCl by way of preparation of microspheres and ODTs of acceptable characteristics.
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Affiliation(s)
- Sanjay Shah
- Delhi Institute of Pharmaceutical Sciences & Research (Formerly College of Pharmacy), University of Delhi, Pushp Vihar, Sector III, New Delhi, 110017, India
| | - Sarika Madan
- Delhi Institute of Pharmaceutical Sciences & Research (Formerly College of Pharmacy), University of Delhi, Pushp Vihar, Sector III, New Delhi, 110017, India
| | - SS Agrawal
- Delhi Institute of Pharmaceutical Sciences & Research (Formerly College of Pharmacy), University of Delhi, Pushp Vihar, Sector III, New Delhi, 110017, India
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Jelvehgari M, Nokhodchi A, Rezapour M, Valizadeh H. Effect of formulation and processing variables on the characteristics of tolmetin microspheres prepared by double emulsion solvent diffusion method. Indian J Pharm Sci 2011; 72:72-8. [PMID: 20582193 PMCID: PMC2883230 DOI: 10.4103/0250-474x.62251] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2009] [Revised: 10/17/2009] [Accepted: 12/28/2009] [Indexed: 12/03/2022] Open
Abstract
The aim of this study was to evaluate microencapsulated controlled release preparations of tolmetin sodium using ethylcellulose as a retardant material. Microspheres were prepared by using water-in-oil-in-oil (W/O1/O2) double-emulsion solvent diffusion method, using different ratios of ethylcellulose to tolmetin sodium. Span 80 was used as the droplet stabilizer and n-hexane was added to harden the microspheres. The prepared microspheres were characterized for their micromeritic properties, drug content, loading efficiency, production yield, and particle size. Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray powder diffractometry and scanning electron microscopy were used to characterize microparticles. The in vitro release studies were performed in pH 1.2 and 7.4. The prepared microspheres were spherical in shape. The drug-loaded microspheres showed near to the theoretical of entrapment and release was extended up to 24. The X-ray diffractogram and differential scanning thermographs showed amorphous state of the drug in the microspheres. It was shown that the drug: polymer ratio, stirring rate, volume of dispersing medium and surfactant influenced the drug loading, particle size and drug release behavior of the formed microparticles. The results showed that, generally, an increase in the ratio of drug: polymer (0.5:1) resulted in a reduction in the release rate of the drug which may be attributed to the hydrophobic nature of the polymer. The in vitro release profile could be modified by changing various processing and formulation parameters to give a controlled release of drug from the microparticules. The release of tolmetin was influenced by the drug to polymer ratio and particle size and was found to be diffusion and erosion controlled. The best-fit release kinetic was achieved with Peppas model.
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Affiliation(s)
- M Jelvehgari
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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Jelvehgari M, Barar J, Nokhodchi A, Shadrou S, Valizadeh H. Effects of process variables on micromeritic properties and drug release of non-degradable microparticles. Adv Pharm Bull 2011; 1:18-26. [PMID: 24312752 DOI: 10.5681/apb.2011.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 07/05/2011] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION The purpose of this investigation was to evaluate microencapsulated controlled release preparation of theophylline using Eudragit RS 100 as the retardant material with high entrapment efficiency. METHODS Microspheres were prepared by the emulsion-solvent evaporation method. A mixed solvent system consisting of methanol and acetone and light liquid paraffin as oily phase were chosen. Sucrose stearate was used as the surfactant to stabilize the emulsification process. The prepared microspheres were characterized by drug loading, Fourier-transform infrared spectroscopy (FTIR), differential scanning colorimetry (DSC) and scanning electron microscopy (SEM). The in vitro release studies were performed at pH 1.2 and 7.4 aqueous medium. RESULTS Increasing the concentration of emulsifier, sucrose fatty acid ester F-70, decreased the particle size which contributed to increased drug release rate. The drug loading microparticle Eudragit RS100(1:6) showed 60-75% of entrapment and mean particle size 205.93-352.76 μm.The results showed that, an increase in the ratio of polymer: drug (F5, 6: 1) resulted in a reduction in the release rate of the drug which may be attributed to the hydrophobic nature of the polymer. CONCLUSION The release of theophylline is influenced by the drug to polymer ratio and particle size. Drug release is controlled by diffusion and the best-fit release kinetic is Higuchi model.
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Affiliation(s)
- Mitra Jelvehgari
- Faculty of Pharmacy, Tabriz University of Medical Sciences, Iran. ; Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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Hussein A, Fetih G. Novel optimization of shape, swelling and release behaviors of tolmetin sodium loaded alginate microbeads. J Drug Deliv Sci Technol 2011. [DOI: 10.1016/s1773-2247(11)50018-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Jelvehgari M, Valizadeh H, Rezapour M, Nokhodchi A. Control of encapsulation efficiency in polymeric microparticle system of tolmetin. Pharm Dev Technol 2010; 15:71-9. [PMID: 19505209 DOI: 10.3109/10837450903002173] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Ethylcellulose microparticles containing tolmetin sodium, an anti-inflammatory drug, were prepared by a solvent diffusion method based on the formation of multiple W/O(1)/O(2)-emulsion. The drug used was TOL, which is water-soluble and n-hexane was used as the non-solvent. Important parameters in the evaluation of a microencapsulation technique are actual drug loading, the encapsulation efficiency, the yield, solvent systems, dispersed phase to continuous phase ratio (DP/CP ratio), composition of continuous phase, drug distribution in microparticles and stability of primary emulsion. A small volume of internal aqueous phase and volume of organic solvent were favorable to achieve high drug encapsulation efficiencies. Since drug release during the initial stages depends mostly on the diffusion escape of the drug, major approaches to prevent the initial burst have focused on efficient encapsulation of the drug within the microparticles. For this reason, control of efficiency and the extent of initial burst are based on common formulation parameters. Most parameters affect encapsulation efficiency and initial burst by modifying solidification rate of dispersed phase. In order to prevent many unfavorable events such as pore formation, drug loss, and drug migration that occur while the dispersed phase is in the semi-solid state, it is important to understand and optimize these variables.
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Affiliation(s)
- Mitra Jelvehgari
- Department of Pharmaceutics, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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Jelvehgari M, Zakeri-Milani P, Siahi-Shadbad MR, Loveymi BD, Nokhodchi A, Azari Z, Valizadeh H. Development of pH-sensitive insulin nanoparticles using Eudragit L100-55 and chitosan with different molecular weights. AAPS PharmSciTech 2010; 11:1237-42. [PMID: 20686881 DOI: 10.1208/s12249-010-9488-7] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Accepted: 07/23/2010] [Indexed: 11/30/2022] Open
Abstract
Insulin is a polypeptide hormone and usually administered for treatment of diabetic patients subcutaneously. The aim of this study was to investigate the efficiency of enteric nanoparticles for oral delivery of insulin. Nanoparticles were formed by complex coacervation method using chitosan of various molecular weights. Nanoparticles were characterized by drug loading efficiency determination, particle size analysis, Scanning Electron Microscopy (SEM), Zeta potential and CD spectroscopy (Circular Dichrosim). The in vitro release studies were performed at pH 1.2 and 7.4. The drug loaded nanoparticles showed 3.38% of entrapment, loading efficiency of 30.56% and mean particle size of 199 nm. SEM studies showed that the nanoparticles are non-spherical. Zeta potential increased with increasing molecular weight of chitosan. The CD spectroscopy profiles indicated that the nano-encapsulation process did not significantly disrupt the internal structure of insulin; additionally, pH-sensitivity of nanoparticles was preserved and the insulin release was pH-dependent. These results suggest that the complex coacervation process using chitosan and Eudragit L100-55 polymers may provide a useful approach for entrapment of hydrophilic polypeptides without affecting their conformation.
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Micromeritics and release behaviours of cellulose acetate butyrate microspheres containing theophylline prepared by emulsion solvent evaporation and emulsion non-solvent addition method. Arch Pharm Res 2009; 32:1019-28. [PMID: 19641883 DOI: 10.1007/s12272-009-1707-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Revised: 05/26/2009] [Accepted: 06/10/2009] [Indexed: 10/20/2022]
Abstract
The present research work compares the effect of microsphere preparation technique on micromeritics and release behaviors of theophylline microspheres. Microspheres were prepared by oil-in oil (O(1)/O(2)) emulsion solvent evaporation method (ESE) using different ratios of anhydrous theophylline to cellulose acetate butyrate (CAB). Cyclohexane was used as non-solvent to modify the ESE technique (MESE method) and the effect of non-solvent volume on properties of microspheres was investigated. The obtained microspheres were analyzed in terms of drug content, particle size and encapsulation efficiency. The morphology of microsphere was studied using scanning electron microscope. The solid state of microspheres, theophylline and CAB were investigated using X-ray, FT-IR and DSC. The drug content of microspheres prepared by MESE method was significantly lower (15.54% +/- 0.46) than microspheres prepared by ESE method (41.08 +/- 0.40%). The results showed that as the amount of cyclohexane was increased from 2 mL to 6 mL the drug content of microspheres was increased from 15.54% to 28.71%. Higher encapsulation efficiencies were obtained for microspheres prepared by ESE method (95.87%) in comparison with MESE method (64.71%). Mean particle size of microsphere prepared by ESE method was not remarkably affected by drug to polymer ratio, whereas in MSES method when the volume of cyclohexane was increased the mean particle size of microsphere was significantly decreased. The ratio of drug to polymer significantly changed the rate of drug release from microspheres and the highest drug release was obtained for the microsphere with high drug to polymer ratio. The amount of cyclohexane did not significantly change the drug release. Although, x-ray showed a small change in crystallinity of theophylline in microspheres, DSC results proved that theophylline in microspheres is in amorphous state. No major chemical interaction between the drug and polymer was reported during the encapsulation process.
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Şengel-Türk CT, HasÇİÇek C, Gönül N. Microsphere-based once-daily modified release matrix tablets for oral administration in angina pectoris. J Microencapsul 2008; 25:257-66. [DOI: 10.1080/02652040801967228] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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Adibkia K, Omidi Y, Siahi MR, Javadzadeh AR, Barzegar-Jalali M, Barar J, Maleki N, Mohammadi G, Nokhodchi A. Inhibition of Endotoxin-Induced Uveitis by Methylprednisolone Acetate Nanosuspension in Rabbits. J Ocul Pharmacol Ther 2007; 23:421-32. [PMID: 17900230 DOI: 10.1089/jop.2007.0039] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE In this study, nanoformulations of methylprednisolone acetate (MPA) were formulated by using a copolymer of poly(ethylacrylate, methyl-methacrylate and chlorotrimethyl-ammonioethyl methacrylate) to study their impacts on the inhibition of inflammatory symptoms in rabbits with endotoxin-induced uveitis (EIU). METHODS A modified quasiemulsion solvent diffusion technique was used for the preparation of the nanoparticles. The drug-release profiles and physicochemical characteristics of the nanoformulations were studied by means of X-ray crystallography, differential scanning calorimetry, and Fourier transform infrared spectroscopy. Particle-size analysis yielded mean diameters of approximately 380, 460, and 580 (nm) for copolymer nanoparticles at the ratios of 1:2.5, 1:5, and 1:10, respectively. Major clinical symptoms of EIU (e.g., morphologic changes, leukocytes numbers, and protein levels within the aqueous humor) were examined. RESULTS Upon the physicochemical characterizations, no crystal changes or chemical interactions were observed for the copolymer nanoparticles. The 1:2.5 ratio of drug polymer resulted in the most controlled release of MPA. The in vivo examinations revealed that the endotoxin-induced inflammation can be inhibited by the copolymer nanosuspension more significantly than by the microsuspension of MPA itself in the rabbits with EIU. CONCLUSIONS Based on our findings, we suggest that the copolymer nanosuspension may favor the localized, controlled ocular delivery of MPA for the prevention of inflammatory symptoms in ocular diseases.
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Affiliation(s)
- Khosro Adibkia
- Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences, Tabriz, Iran
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Hombreiro-Pérez M, Siepmann J, Zinutti C, Lamprecht A, Ubrich N, Hoffman M, Bodmeier R, Maincent P. Non-degradable microparticles containing a hydrophilic and/or a lipophilic drug: preparation, characterization and drug release modeling. J Control Release 2003; 88:413-28. [PMID: 12644367 DOI: 10.1016/s0168-3659(03)00030-0] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Non-degradable microparticles based on ammonio methacrylate copolymers (Eudragit RS:RL 4:1 blends) containing the hydrophilic drug propranolol HCl and/or the lipophilic drug nifedipine were prepared with an oil-in-water (O/W) and a water-in-oil-in-water (W/O/W) solvent evaporation technique. Both drugs were successfully incorporated separately as well as simultaneously. In all cases, the resulting release rate(s) of the drug(s) was/were found to be controlled over periods of at least 8 h. To elucidate the underlying mass transport mechanisms, the microparticles were thoroughly characterized by X-ray powder diffractometry, differential scanning calorimetry, particle size analysis, and determination of the actual drug loading(s). Analytical solutions of Fick's second law of diffusion considering non-steady state conditions were used to describe the release of propranolol HCl. Interestingly, the resistance for drug release within the unstirred liquid boundary layers on the surfaces of the microparticles was found to be negligible compared to the diffusional resistance within the polymeric devices. Importantly, the mathematical theories could be used to normalize the experimentally determined in vitro drug release with respect to the microparticle size. Thus, the effect of the type of preparation method (O/W vs. W/O/W) and device composition (polymer blend plus one drug only vs. polymer blend plus drug combination) on the diffusional resistance within the microparticles could be studied. In addition, further insight into the occurring mass transport processes was gained. For example, the time-dependent evolution of the drug concentration profiles within the microparticles upon exposure to the release medium could be calculated. An interesting practical application of the mathematical theories is the possibility to predict the effect of different formulation parameters on the resulting drug release patterns, e.g. the effect of the microparticle size.
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Affiliation(s)
- M Hombreiro-Pérez
- Laboratoire de Pharmacie Galénique et Biopharmacie, Université de Nancy I, 5 rue A Lebrun, BP 403, 54001 Nancy, Cedex, France
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Pignatello R, Bucolo C, Spedalieri G, Maltese A, Puglisi G. Flurbiprofen-loaded acrylate polymer nanosuspensions for ophthalmic application. Biomaterials 2002; 23:3247-55. [PMID: 12102196 DOI: 10.1016/s0142-9612(02)00080-7] [Citation(s) in RCA: 184] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Polymeric nanoparticle suspensions were prepared from Eudragit RS100R and RL100R polymer resins and loaded with flurbiprofen (FLU), with the aim at improving the availability of the drug at an intra-ocular level for the prevention of the myosis induced during extracapsular cataract surgery. Nanosuspensions were prepared by a quasi-emulsion solvent diffusion technique using different formulation parameters (drug-to-polymer ratio, initial polymer concentration, agitation speed, etc.). The resulting nanoparticles showed mean sizes around 100 nm and a fixed positive charge (zeta-potential around +40/+60 mV). Stability tests after mid-time storage (4 degrees C or room temperature) or freeze-drying were carried out to optimise a possible final pharmaceutical preparation. In vitro, dissolution tests showed a controlled release profile of FLU from the nanoparticles. In vivo anti-inflammatory efficacy was assessed in the rabbit eye after induction of an ocular trauma (paracentesis). FLU-loaded nanosuspensions did not show toxicity on ocular tissues. Moreover, an inhibition of the miotic response to the surgical trauma comparable to a control eye-drop formulation was obtained, even though an actual lower concentration of free drug in the conjunctival sac was achieved from the nanoparticle system. Drug levels in the aqueous humour were also higher after application of the nanosuspensions.
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Affiliation(s)
- R Pignatello
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Catania, Città Universitaria, Itay.
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Pignatello R, Bucolo C, Ferrara P, Maltese A, Puleo A, Puglisi G. Eudragit RS100 nanosuspensions for the ophthalmic controlled delivery of ibuprofen. Eur J Pharm Sci 2002; 16:53-61. [PMID: 12113891 DOI: 10.1016/s0928-0987(02)00057-x] [Citation(s) in RCA: 238] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Topical application of non-steroidal anti-inflammatory drugs on the eye is a common treatment used to contrast the miosis induced by surgical traumas, such as cataract extraction. With the aim of improving the availability of sodium ibuprofen (IBU) at the intraocular level, IBU-loaded polymeric nanoparticle suspensions were made from inert polymer resins (Eudragit RS100). The nanosuspensions were prepared by a modification of the quasi-emulsion solvent diffusion technique using variable formulation parameters (drug-to-polymer ratio, total drug and polymer amount, stirring speed). Nanosuspensions had mean sizes around 100 nm and a positive charge (zeta-potential of +40/+60 mV), this makes them suitable for ophthalmic applications. Stability tests (up to 24 months storage at 4 degrees C or at room temperature) or freeze-drying were carried out to optimize a suitable pharmaceutical preparation. In vitro dissolution tests indicated a controlled release profile of IBU from nanoparticles. In vivo efficacy was assessed on the rabbit eye after induction of an ocular trauma (paracentesis). An inhibition of the miotic response to the surgical trauma was achieved, comparable to a control aqueous eye-drop formulation, even though a lower concentration of free drug in the conjunctival sac was reached from the nanoparticle system. Drug levels in the aqueous humour were also higher after application of the nanosuspensions; moreover, IBU-loaded nanosuspensions did not show toxicity on ocular tissues.
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Affiliation(s)
- Rosario Pignatello
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Catania, Città Universitaria, viale A. Doria, 6 - 95125, Catania, Italy.
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Pignatello R, Ferro M, Puglisi G. Preparation of solid dispersions of nonsteroidal anti-inflammatory drugs with acrylic polymers and studies on mechanisms of drug-polymer interactions. AAPS PharmSciTech 2002; 3:E10. [PMID: 12916947 PMCID: PMC2750312 DOI: 10.1208/pt030210] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
This work studied the mechanisms of interaction between Eudragit RS100 (RS) and RL100 (RL) polymers with 3 nonsteroidal anti-inflammatory drugs: diflunisal (DIF), flurbiprofen (FLU), and piroxicam (PIR). Solid dispersions of polymers and drugs at different weight ratios were prepared by coevaporation of their ethanol solutions. The resulting coevaporates were characterized in the solid state (Fourier-transformed infrared spectroscopy (FT-IR) IR, differential scanning calorimetry, powder-x-ray diffractometry) as well as by studying the in vitro drug release in a gastroenteric environment. Absorption tests from drug solutions to the solid polymers were also performed to better explain the mechanism of interactions between them. The preparative conditions did not induce changes in the crystalline state of the drugs (amorphization or polymorphic change). Drugs strongly interacted with the ammonium groups present in polymers, giving an electrostatic interaction that reinforced the mere physical dispersion of drug molecules within polymer networks. Such interactions are related to the chemical structure of the drugs and to their dissociated or undissociated state. The dispersion of drugs in the polymer matrices strongly influenced their dissolution rate, which appeared slower and more gradual than those of the pure drugs, when polymer ratios were increased. RL coevaporates usually displayed higher dissolution rates. The kinetic evaluation of the dissolution profile, however, suggested that both the drug solubility in the external medium and its diffusion capacity within the polymer network are involved. In the sorption experiments, RL showed a greater adsorptive capacity than RS, in relation to the greater number of quaternary ammonium functions, which behave as activity sites for the electrostatic interactions. In the presence of Tris-HCl buffer (pH 7.4), drug adsorption was reduced, as a consequence of the competition of the chloride ions with drug anions for the polymer binding sites. In general, DIF and FLU displayed a similar interaction with RS and RL active sites; PIR's was different. The different molecular structures of these agents can justify such findings. The presence of a carboxyl group (instead of another dissociable acidic moiety, like the hydroxy-enolic one in the PIR molecule) could help explain the strong interaction with RS and RL polymers' quaternary ammonium centers. Preliminary studies like ours are important in helping develop better forecasting and increasing the understanding of the incorporation/release behavior of drugs from particulate delivery systems that can be made from these polymers.
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Affiliation(s)
- Rosario Pignatello
- Dipartimento di Scienze Farmaceutiche, Universita di Catania, viale A. Doria, 6-I-95125 Catania, Italy.
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Pignatello R, Amico D, Chiechio S, Spadaro C, Puglisi G, Giunchedi P. Preparation and analgesic activity of Eudragit RS100 microparticles containing diflunisal. Drug Deliv 2001; 8:35-45. [PMID: 11280442 DOI: 10.1080/107175401300002748] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
Two different techniques, the quasi-emulsion solvent diffusion method and spray drying that provide polar and nonpolar preparation environments, were used to prepare microspheres from Eudragit RS100 (RS) (acrylic/methacrylic copolymer) incorporating the nonsteroidal anti-inflammatory drug diflunisal. The effects of pH on the preparation medium and drug/polymer ratio on production yield and drug incorporation, as well as on the in vitro drug release at pH 1.2 and 6.8 from tabletted microparticles, were evaluated. The drug-polymer interactions and the effect of diflunisal incorporation in the polymer matrix on drug crystallinity have been evaluated by using differential scanning calorimetry, IR and ultraviolet spectroscopy, x-ray diffraction, and microscopy analysis. A preliminary biological assay confirmed that diflunisal maintains its analgesic activity after intraperitoneal administration to rats.
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Affiliation(s)
- R Pignatello
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Catania, Italy.
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Literature alerts. J Microencapsul 2000; 17:789-99. [PMID: 11063426 DOI: 10.1080/02652040050161783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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