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Abdullah S, Bani-Jaber A, Alhakamy NA, Jamous YF, Al-Masud AA, Marzoog Al-Sharafa M. Preparation and in vitro/in vivo characterization of sustained-release ciprofloxacin-carrageenan complex. Eur J Pharm Biopharm 2023; 191:78-89. [PMID: 37619955 DOI: 10.1016/j.ejpb.2023.08.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 08/16/2023] [Accepted: 08/20/2023] [Indexed: 08/26/2023]
Abstract
The goal of the study was to look into drug-polyelectrolyte complexation between ciprofloxacin (Cipro) and λ-carrageenan (CRG), and to employ the complex as a sustained-release matrix. The maximum binding capacity of the complexation was determined using the dialysis bag method and employed to prepare the complex. In comparison to Cipro, CRG, and their physical mixing, the complex was examined using differential scanning calorimetry, Fourier infrared spectroscopy, powder X-ray diffraction, and scanning electron microscopy. Cipro-CRG matrices, manufactured as direct compression tablets based on the greatest binding capacity, were assessed for swelling, erosion and drug release in 0.1 M HCl, in comparison with those of CRG, Hydroxypropyl methylcellulose (HPMC) and Cipro-HPMC matrices. In vivo absorption study comparing the Cipro-CRG matrix to Cipro immediate-release tablet was also carried out. The greatest binding capacity of Cipro to CRG was 55% (w/w). Multiple interactions, including electrostatic interaction, Vander wall forces, and hydrogen bonding, have been proposed to be involved in complexation with drug amorphization. As a result of the complexation, the swelling and erosion properties of CRG changed, with Cipro-CRG matrix showing substantially less swelling and erosion than Cipro-free CRG matrix. Cipro-CRG matrix exhibited swelling and erosion similar to Cipro-HPMC matrix. However, the former matrix demonstrated Cipro release with significantly less burst impact and a significantly slower release rate. Furthermore, Cipro-CRG matrices in vivo demonstrated slow-prolonged oral drug absorption with consequent significant changes in pharmacokinetic parameters in comparison to those obtained for immediate-release tablets.
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Affiliation(s)
- Samaa Abdullah
- Health Sciences Research Centre, Princess Nourah bint Abdulrahman University, Riyadh 84428, Saudi Arabia.
| | - Ahmad Bani-Jaber
- Department of Pharmaceutics and Pharmaceutical Technology, School of Pharmacy, The University of Jordan, Amman, Jordan.
| | - Nabil A Alhakamy
- Department of Pharmaceutics, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia; Center of Excellence for Drug Research Pharmaceutical Industries, King Abdulaziz University, Jeddah, Saudi Arabia; Mohamed Saeed Tamer Chair for Pharmaceutical Industries, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Yahya F Jamous
- The National Centre of Vaccines and Bioprocessing, King Abdulaziz City for Science and Technology (KACST), Riyadh, Saudi Arabia
| | - Alaa A Al-Masud
- Tissue Banking Section, Research Department, Health Science Research Center, Princess Nourah bint Abdulrahman University, Riyadh 84428, Saudi Arabia
| | - Meshal Marzoog Al-Sharafa
- Tissue Banking Section, Research Department, Health Science Research Center, Princess Nourah bint Abdulrahman University, Riyadh 84428, Saudi Arabia
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2
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Tudu M, Samanta A. Natural polysaccharides: Chemical properties and application in pharmaceutical formulations. Eur Polym J 2022. [DOI: 10.1016/j.eurpolymj.2022.111801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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3
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Chaves PS, Dos Santos J, Pohlmann AR, Guterres SS, Beck RCR. Sublingual tablets containing spray-dried carvedilol-loaded nanocapsules: development of an innovative nanomedicine. Pharm Dev Technol 2020; 25:1053-1062. [DOI: 10.1080/10837450.2020.1785498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- P. S. Chaves
- Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - J. Dos Santos
- Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - A. R. Pohlmann
- Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Departamento de Química Orgânica, Instituto de Química, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - S. S. Guterres
- Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - R. C. R. Beck
- Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
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Diener M, Adamcik J, Mezzenga R. Formation of Higher Structural Levels in λ-Carrageenan Induced by the Antimalarial Drug Chloroquine. ACS Macro Lett 2020; 9:1310-1317. [PMID: 35638640 DOI: 10.1021/acsmacrolett.0c00501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The linear polysaccharide λ-carrageenan is the only one among the carrageenans not forming secondary, tertiary, and quaternary structures in the presence of inorganic ions. Chloroquine (CQ) is a well-established antimalaria drug also recently discussed in therapeutics against the COVID-19 pandemic. The interaction of this polysaccharide-ionic drug pair was investigated by combining UV-vis spectrophotometry and atomic force microscopy (AFM) imaging. A decrease of the UV peak assigned to free CQ and the occurrence of isosbestic points indicate the formation of complexes. High-resolution AFM height images revealed an increasing height of the single polysaccharide chains in the random coil state upon addition of CQ, indicating the formation of a secondary structure, followed by higher hierarchical aggregates. The disappearance of higher-ordered structures and the recovery of polysaccharide chains with primary structure were observed by introducing inorganic cations (Na+, K+, Ca2+), replacing the condensed CQ and paving the way to reversible ion-induced drug release.
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Affiliation(s)
- Michael Diener
- Department of Health Sciences and Technology, Swiss Federal Institute of Technology Zurich, 8092 Zurich, Switzerland
| | - Jozef Adamcik
- Department of Health Sciences and Technology, Swiss Federal Institute of Technology Zurich, 8092 Zurich, Switzerland
| | - Raffaele Mezzenga
- Department of Health Sciences and Technology, Swiss Federal Institute of Technology Zurich, 8092 Zurich, Switzerland.,Department of Materials, Swiss Federal Institute of Technology Zurich, 8092 Zurich, Switzerland
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5
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Zendeboodi F, Farahnaky A, Gholian MM. Structural changes and stress relaxation behavior of κ-carrageenan cold-processed gels: Effects of ultrasonication time and power. J Texture Stud 2019; 50:465-473. [PMID: 31206693 DOI: 10.1111/jtxs.12457] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 05/23/2019] [Accepted: 05/31/2019] [Indexed: 01/06/2023]
Abstract
Ultrasound has been used for cold gelation of κ-carrageenan hydrocolloid. In this work, the effect of ultrasound conditions such as power (50-150 W) and time (20-240 s) of sonication has been investigated. The application of ultrasound to hydrocolloid dispersion caused an increase in water solubility. The texture profile analysis test was used in order to evaluate the mechanical properties of gels. Textural parameters of κ-carrageenan gels, enhanced with increasing sonication time and power up to a certain level (usually 2.5 min) and longer sonication times had negative effects. In addition, intrinsic viscosities of sonicated specimens were measured to investigate the molecular characteristics of all samples. An increase in the process time and power reduced the intrinsic viscosity. The microstructural observation by scanning electron microscope determined that applying power ultrasound on κ-carrageenan dispersions influenced the formation of gel networks significantly.
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Affiliation(s)
- Fetemeh Zendeboodi
- Research Institute of Food Science and Technology (RIFST), Mashhad, Iran
| | - Asgar Farahnaky
- Department of Food Science and Technology, School of Agriculture, Shiraz University, Shiraz, Iran
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6
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pH-dependent release of antihypertensives from complexes with poly(carboxyalkyl methacrylamides). J Drug Deliv Sci Technol 2017. [DOI: 10.1016/j.jddst.2017.05.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Cunha L, Grenha A. Sulfated Seaweed Polysaccharides as Multifunctional Materials in Drug Delivery Applications. Mar Drugs 2016; 14:E42. [PMID: 26927134 PMCID: PMC4820297 DOI: 10.3390/md14030042] [Citation(s) in RCA: 272] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 02/10/2016] [Accepted: 02/15/2016] [Indexed: 02/07/2023] Open
Abstract
In the last decades, the discovery of metabolites from marine resources showing biological activity has increased significantly. Among marine resources, seaweed is a valuable source of structurally diverse bioactive compounds. The cell walls of marine algae are rich in sulfated polysaccharides, including carrageenan in red algae, ulvan in green algae and fucoidan in brown algae. Sulfated polysaccharides have been increasingly studied over the years in the pharmaceutical field, given their potential usefulness in applications such as the design of drug delivery systems. The purpose of this review is to discuss potential applications of these polymers in drug delivery systems, with a focus on carrageenan, ulvan and fucoidan. General information regarding structure, extraction process and physicochemical properties is presented, along with a brief reference to reported biological activities. For each material, specific applications under the scope of drug delivery are described, addressing in privileged manner particulate carriers, as well as hydrogels and beads. A final section approaches the application of sulfated polysaccharides in targeted drug delivery, focusing with particular interest the capacity for macrophage targeting.
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Affiliation(s)
- Ludmylla Cunha
- Centre for Marine Sciences, University of Algarve, 8005-139 Faro, Portugal.
- Drug Delivery Laboratory, Centre for Biomedical Research (CBMR), Faculty of Sciences and Technology, University of Algarve, Gambelas Campus, 8005-139 Faro, Portugal.
| | - Ana Grenha
- Centre for Marine Sciences, University of Algarve, 8005-139 Faro, Portugal.
- Drug Delivery Laboratory, Centre for Biomedical Research (CBMR), Faculty of Sciences and Technology, University of Algarve, Gambelas Campus, 8005-139 Faro, Portugal.
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Drug release kinetics and front movement in matrix tablets containing diltiazem or metoprolol/λ-carrageenan complexes. BIOMED RESEARCH INTERNATIONAL 2014; 2014:671532. [PMID: 25045689 PMCID: PMC4090483 DOI: 10.1155/2014/671532] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 05/08/2014] [Accepted: 05/28/2014] [Indexed: 11/17/2022]
Abstract
In this work we investigated the moving boundaries and the associated drug release kinetics in matrix tablets prepared with two complexes between λ-carrageenan and two soluble model drugs, namely, diltiazem HCl and metoprolol tartrate aiming at clarifying the role played by drug/polymer interaction on the water uptake, swelling, drug dissolution, and drug release performance of the matrix. The two studied complexes released the drug with different mechanism indicating two different drug/polymer interaction strengths. The comparison between the drug release behaviour of the complexes and the relevant physical mixtures indicates that diltiazem gave rise to a less soluble and more stable complex with carrageenan than metoprolol. The less stable metoprolol complex afforded an erodible matrix, whereas the stronger interaction between diltiazem and carrageenan resulted in a poorly soluble, slowly dissolving matrix. It was concluded that the different stability of the studied complexes affords two distinct drug delivery systems: in the case of MTP, the dissociation of the complex, as a consequence of the interaction with water, affords a classical soluble matrix type delivery system; in the case of DTZ, the dissolving/diffusing species is the complex itself because of the very strong interaction between the drug and the polymer.
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Buchholcz G, Kelemen A, Sovány T, Pintye-Hódi K. Matrix tablets based on a carrageenan with the modified-release of sodium riboflavin 5'-phosphate. Pharm Dev Technol 2014; 20:676-83. [PMID: 24758384 DOI: 10.3109/10837450.2014.910810] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The focus of this work was to produce modified-release monolithic matrix tablets containing sodium riboflavin 5'-phosphate (vitamin B2) as active pharmaceutical ingredient (API). Riboflavin 5'-phosphate is absorbed from the upper gastrointestinal tract by a specific transport mechanism. The aim of this work was the development of modified-release tablets from which most or the entire API can dissolve within 5 h. The dissolution was started in medium pH 1.2 (gastric juice) and finished in medium pH 4.5. The matrix former was iota-carrageenan combined with microcrystalline cellulose (MCC) and lactose in different ratios. Factorial design was used in this work so as to study the effects of the MCC/lactose ratio on the parameters of the tablets, and especially on the dissolution process. The dissolution data were subjected to statistical analysis, and the release profiles were fitted with different models. It was found that the MCC/lactose ratio influenced the quality of the tablets to a high degree. The Korsmeyer-Peppas model proved to characterize the total dissolution profile best, but fitting of the separate sections was also possible with a linear model.
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10
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Li L, Ni R, Shao Y, Mao S. Carrageenan and its applications in drug delivery. Carbohydr Polym 2014; 103:1-11. [DOI: 10.1016/j.carbpol.2013.12.008] [Citation(s) in RCA: 354] [Impact Index Per Article: 35.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 12/02/2013] [Accepted: 12/03/2013] [Indexed: 12/30/2022]
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11
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Enhanced bioavailability of poorly absorbed hydrophilic compounds through drug complex/in situ gelling formulation. Int J Pharm 2013; 457:63-70. [PMID: 24004566 DOI: 10.1016/j.ijpharm.2013.07.066] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 07/09/2013] [Accepted: 07/19/2013] [Indexed: 11/21/2022]
Abstract
BCS class III hydrophilic compounds are often associated with low oral bioavailability due to their poor epithelial permeability in the gastrointestinal tract. In this study, we reported an approach of incorporating a drug complex into an in situ gelling muco-adhesive carrier to achieve an improved bioavailability of a poorly absorbed hydrophilic compound. A new molecular entity (RWJ-445167) from Johnson and Johnson was used as a model compound. The compound was first complexed with sodium lauryl sulfate (SLS). The complex was then incorporated into an in situ gelling muco-adhesive carrier Cremophor for formulation characterization and rat pharmacokinetic (PK) studies. The study results showed that RWJ-445167 bound to SLS at a stoichiometric ratio. By complexing with SLS, the compound became lipophilic. The aqueous solubility of RWJ-445167 dropped to 0.58 mg/mL for the complex from 61 mg/mL for the free compound, while the partitioning coefficient of the complex increased to 7.59, compared with 0.05 of the free compound. In the rat PK study, with duodenal administration, the complex in the in situ-gelling formulation achieved 28.24% of bioavailability, compared to 4.26% of the free compound solution. The enhanced bioavailability was also significantly higher than those in the RWJ-445167/SLS physical mixture in Cremophor (14.91%), the complex in non-gelling carrier PEG 400 (9.95%) and the RWJ-445167/SLS physical mixture in PEG 400 carrier (8.60%). The study demonstrates that incorporation of a drug complex into an in situ gelling formulation provides a new approach to improving bioavailability of BCS class III drugs.
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12
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Avramoff A, Khan W, Mizrahi B, Domb AJ. Preparation and characterization of a novel once-daily formulation of diltiazem using arabinogalactan as a channeling agent. J Appl Polym Sci 2012. [DOI: 10.1002/app.36755] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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13
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Ku MS, Lu Q, Li W, Chen Y. Performance qualification of a new hypromellose capsule: Part II. Disintegration and dissolution comparison between two types of hypromellose capsules. Int J Pharm 2011; 416:16-24. [PMID: 21356291 DOI: 10.1016/j.ijpharm.2011.02.048] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Revised: 01/26/2011] [Accepted: 02/21/2011] [Indexed: 11/30/2022]
Abstract
This Part II paper describes the disintegration and dissolution aspects of the qualification of a new hypromellose capsule (HPMC Shell 2). This new capsule does not contain any gelling agent, and is manufactured by a thermal gelation process. Rupture time of the carrageenan-containing capsule (HPMC Shell 1) and HPMC Shell 2, as measured by an improved real-time detection method, showed only slight differences that did not manifest in vivo. The absence of a gelling agent appeared to give HPMC Shell 2 advantages in dissolution in acidic media and in buffers containing potassium ions. Slow drug release of HPMC Shell 1 in 0.1M HCl was attributed to the interaction of carrageenan with drug compounds; whereas the presence of potassium ions, a gelling promoter for carrageenan, caused delay in capsule opening and larger capsule-to-capsule variation. Disintegration and dissolution performances of both hypromellose capsules are comparable in other dissolution media tested. Based on the superior dissolution performances and quality attributes in terms of physical, mechanical and processability that were detailed in Paper I, the new hypromellose capsule was satisfactorily qualified and has since been used in nearly 20 investigational new drug (IND) compounds.
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Affiliation(s)
- M Sherry Ku
- Pharmaceutical Development, Wyeth Research, Pearl River, NY 10965, USA
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14
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Colombo P, Sonvico F, Colombo G, Bettini R. Novel platforms for oral drug delivery. Pharm Res 2009; 26:601-11. [PMID: 19132514 DOI: 10.1007/s11095-008-9803-0] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2008] [Accepted: 12/01/2008] [Indexed: 11/29/2022]
Abstract
The aim of this review is to provide the reader general and inspiring prospects on recent and promising fields of innovation in oral drug delivery. Nowadays, inventive drug delivery systems vary from geometrically modified and modular matrices, more close to "classic" pharmaceutical manufacturing processes, to futuristic bio micro-electro-mechanical systems (bioMEMS), based on manufacturing techniques borrowed from electronics and other fields. In these technologies new materials and creative solutions are essential designing intelligent drug delivery systems able to release the required drug at the proper body location with the correct release rate. In particular, oral drug delivery systems of the future are expected to have a significant impact on the treatment of diseases, such as AIDS, cancer, malaria, diabetes requiring complex and multi-drug therapies, as well as on the life of patients, whose age and/or health status make necessary a multiple pharmacological approach.
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Affiliation(s)
- P Colombo
- Dipartimento Farmaceutico, Università degli Studi di Parma, Viale G.P. Usberti 27/a, 43100, Parma, Italy.
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15
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Vadlapatla R, Fifer EK, Kim CJ, Alexander KS. Drug–Organic Electrolyte Complexes as Controlled Release Systems. Drug Dev Ind Pharm 2009; 35:1-11. [DOI: 10.1080/03639040701842469] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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16
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AlKhatib HS, Aiedeh KM, Bustanji Y, Hamed S, Mohammad M, AlKhalidi B, Najjar S. Modulation of buspirone HCl release from hypromellose matrices using chitosan succinate: Implications for pH-independent release. Eur J Pharm Biopharm 2008; 70:804-12. [DOI: 10.1016/j.ejpb.2008.06.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2008] [Revised: 06/17/2008] [Accepted: 06/18/2008] [Indexed: 10/21/2022]
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17
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Bonferoni MC, Sandri G, Rossi S, Ferrari F, Caramella C, Aguzzi C, Viseras C. Polyelectrolyte–Drug Complexes of Lambda Carrageenan and Basic Drugs: Relevance of Particle Size and Moisture Content on Compaction and Drug Release Behavior. Drug Dev Ind Pharm 2008; 34:1188-95. [DOI: 10.1080/03639040801974337] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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18
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Bari MM, Kim CJ. Noncross-Linked Copolymers of Dimethylaminoethyl Methacrylate and Methacrylic Acid as Oral Drug Carriers. Drug Dev Ind Pharm 2008; 32:531-8. [PMID: 16720408 DOI: 10.1080/03639040600599939] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The purpose of this study was to synthesize new water-soluble ampholytic copolymers consisting of tertiary amine and carboxylic acid pendent groups for oral drug carriers. The polymers were prepared with a 1:1 molar ratio of dimethylaminoethyl methacrylate and methacrylic acid by free radical polymerization. After polymerization, polymer rods were recovered, dissolved (or swollen) in de-ionized water, and freeze-dried before obtaining fine powders. Drug release experiments with various drugs, representing a variety of drug solubility and types of amine, were carried out with compressed tablets (total weight of 600 mg) containing a variety of basic drugs in pH's of 1.5 and 7. Surprisingly, zero-order release kinetics even from a tablet geometry has been obtained with drug loading ranging from 20-50%. Drug release in pH 7 maintains a zero-order rate up to 80-85% release after a slight initial burst, whereas in pH 1.5 one may not find the initial burst and zero-order kinetics is extended up to 90-95% release. Drug release becomes faster in pH 1.5 than pH 7 due to the faster rate of protonation of the tertiary amine in acidic conditions. The release of basic drugs in pH 1.5 is not significantly different even with varying solubility and types of amine (primary, secondary, and tertiary). However, different drug release profiles in pH 7 are observed with different types of amine and solubility.
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Affiliation(s)
- Mohammad M Bari
- School of Pharmacy, Temple University, Philadelphia, PA, USA
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19
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Dai WG, Dong LC, Song YQ. Nanosizing of a drug/carrageenan complex to increase solubility and dissolution rate. Int J Pharm 2007; 342:201-7. [PMID: 17560055 DOI: 10.1016/j.ijpharm.2007.04.032] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2007] [Revised: 04/23/2007] [Accepted: 04/24/2007] [Indexed: 11/28/2022]
Abstract
In this study, we present a novel approach of nanosizing a drug/polymeric complex to increase both solubility and dissolution rate of poorly water-soluble compounds. A hydrophilic polymer, lambda-carrageenan, was first complexed with a model poorly water-soluble compound to increase the compound's aqueous solubility. The compound/carrageenan complex was further nanosized by wet-milling to enhance the dissolution rate. By complexing with carrageenan, the compound became amorphous in the complex. Using additional carrageenan as a stabilizer for nanosizing, a nanosuspension of a compound/carrageenan complex with a median particle size of about 0.3 microm was successfully developed. The particle size of the nanosuspension did not increase significantly during the lyophilization process and was stable for at least 39 days at room temperature after lyophilization. This approach of nanosizing a drug/carrageenan complex increased the aqueous solubility of the compound from less than 1 microg/mL to 39 microg/mL. In addition to increasing aqueous solubility, a nanosized compound/carrageenan complex had a faster dissolution rate than the complex, the free compound, and the nanosuspension of the free compound.
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Affiliation(s)
- Wei-Guo Dai
- ALZA Corporation, 1900 Charleston Road, Mountain View, CA 94039, USA.
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20
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Bonferoni MC, Giunchedi P, Scalia S, Rossi S, Sandri G, Caramella C. Chitosan gels for the vaginal delivery of lactic acid: relevance of formulation parameters to mucoadhesion and release mechanisms. AAPS PharmSciTech 2007; 7:104. [PMID: 17285750 PMCID: PMC2750341 DOI: 10.1208/pt0704104] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The aim of this work was to assess the effect of formulation parameters of a mucoadhesive vaginal gel based on chitosan and lactic acid, and to highlight its release mechanisms. Two molecular weight chitosans were used to prepare gels with 2 lactic acid concentrations. Both chitosan molecular weight and lactic acid concentration had a significant and mutually dependent influence on mucoadhesion, measured on pig vaginal mucosa. Similarly, the lactate release profiles were found to be dependent on lactic acid content and polymer molecular weight. One gel formulation based on the stoichiometric lactate to chitosan ratio was subjected to release test in media with 2 different counterions and increasing ionic strength. This test demonstrated that the lactate release is mainly due to ionic displacement.
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Hrubý M, Subr V, Kucka J, Kozempel J, Lebeda O, Sikora A. Thermoresponsive polymers as promising new materials for local radiotherapy. Appl Radiat Isot 2005; 63:423-31. [PMID: 15996473 DOI: 10.1016/j.apradiso.2005.05.043] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2005] [Revised: 05/15/2005] [Accepted: 05/18/2005] [Indexed: 11/26/2022]
Abstract
We describe a novel thermoresponsive polymeric drug delivery system based on poly(N-isopropylacrylamide) with isotopically labellable end groups [l-tyrosinamide or diethylenetriaminepentaacetic acid (DTPA)] designed for local radiotherapy. The polymers are readily soluble in isotonic aqueous sodium chloride at room temperature and the phase separation is complete at body temperature as proved by DSC measurements. Sufficent binding capacity for radionuclides and chemical stability are demonstrated on 125I and 90Y-labelled polymers.
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Affiliation(s)
- M Hrubý
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovského Sq. 2, 162 06 Prague 6, Czech Republic.
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