1
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Preparation and Characterization of Bioadhesive Monoolein Cubosomes as Carriers for Captopril. J Pharm Innov 2022. [DOI: 10.1007/s12247-022-09618-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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2
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Enck K, Rajan SP, Aleman J, Castagno S, Long E, Khalil F, Hall AR, Opara EC. Design of an Adhesive Film-Based Microfluidic Device for Alginate Hydrogel-Based Cell Encapsulation. Ann Biomed Eng 2020; 48:1103-1111. [PMID: 31933001 PMCID: PMC11071058 DOI: 10.1007/s10439-020-02453-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 01/07/2020] [Indexed: 01/02/2023]
Abstract
To support the increasing translational use of transplanted cells, there is a need for high-throughput cell encapsulation technologies. Microfluidics is a particularly promising candidate technology to address this need, but conventional polydimethylsiloxane devices have encountered challenges that have limited their utility, including clogging, leaking, material swelling, high cost, and limited scalability. Here, we use a rapid prototyping approach incorporating patterned adhesive thin films to develop a reusable microfluidic device that can produce alginate hydrogel microbeads with high-throughput potential for microencapsulation applications. We show that beads formed in our device have high sphericity and monodispersity. We use the system to demonstrate effective cell encapsulation of mesenchymal stem cells and show that they can be maintained in culture for at least 28 days with no measurable reduction in viability. Our approach is highly scalable and will support diverse translational applications of microencapsulated cells.
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Affiliation(s)
- Kevin Enck
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157, USA
- Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157, USA
| | - Shiny Priya Rajan
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157, USA
- Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157, USA
| | - Julio Aleman
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157, USA
| | | | - Emily Long
- Wake Forest Institute for Regenerative Medicine Summer Undergraduate Research Program, Wake Forest School of Medicine, Medical Center, Winston-Salem, NC, 27157, USA
| | - Fatma Khalil
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157, USA
| | - Adam R Hall
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157, USA
- Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157, USA
| | - Emmanuel C Opara
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157, USA.
- Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157, USA.
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3
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Banks SR, Enck K, Wright M, Opara EC, Welker ME. Chemical Modification of Alginate for Controlled Oral Drug Delivery. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:10481-10488. [PMID: 31433940 PMCID: PMC6905053 DOI: 10.1021/acs.jafc.9b01911] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Here, we report two methods that chemically modify alginate to achieve neutral-basic pH sensitivity of the resultant hydrogel. The first method involves direct amide bond formation between alginate and 4-(2-aminoethyl)benzoic acid. The second method that arose out of the desire to achieve better control of the degradation rate of the alginate hydrogel involves reductive amination of oxidized alginate. The products of both methods result in a hydrogel vehicle for targeted delivery of encapsulated payload under physiological conditions in the gastrointestinal tract. Two-dimensional diffusion-ordered spectroscopy and internal and coaxial external nuclear magnetic resonance standards were used to establish chemical bonding and percent incorporation of the modifying groups into the alginate polymer. The hydrogel made with alginate modified by each method was found to be completely stable under acidic pH conditions while disintegrating within minutes to hours in neutral-basic pH conditions. We found that, while alginate oxidation did not affect the β-d-mannuronate/α-l-guluronate ratio of alginate, the rate of disintegration of the hydrogel made with oxidized alginate was dependent upon the degree of oxidation.
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Affiliation(s)
- Surya R Banks
- Department of Chemistry , Wake Forest University , 455 Vine Street , Winston-Salem , North Carolina 27101 , United States
| | - Kevin Enck
- Wake Forest Institute for Regenerative Medicine , Wake Forest School of Medicine , Medical Center Boulevard Winston-Salem , North Carolina 27101 , United States
- Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences , Wake Forest School of Medicine , Medical Center Boulevard , Winston-Salem , North Carolina 27157 , United States
| | - Marcus Wright
- Department of Chemistry , Wake Forest University , 455 Vine Street , Winston-Salem , North Carolina 27101 , United States
| | - Emmanuel C Opara
- Wake Forest Institute for Regenerative Medicine , Wake Forest School of Medicine , Medical Center Boulevard Winston-Salem , North Carolina 27101 , United States
- Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences , Wake Forest School of Medicine , Medical Center Boulevard , Winston-Salem , North Carolina 27157 , United States
| | - Mark E Welker
- Department of Chemistry , Wake Forest University , 455 Vine Street , Winston-Salem , North Carolina 27101 , United States
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4
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Gioumouxouzis CI, Chatzitaki AT, Karavasili C, Katsamenis OL, Tzetzis D, Mystiridou E, Bouropoulos N, Fatouros DG. Controlled Release of 5-Fluorouracil from Alginate Beads Encapsulated in 3D Printed pH-Responsive Solid Dosage Forms. AAPS PharmSciTech 2018; 19:3362-3375. [PMID: 29948989 DOI: 10.1208/s12249-018-1084-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/24/2018] [Indexed: 11/30/2022] Open
Abstract
Three-dimensional printing is being steadily deployed as manufacturing technology for the development of personalized pharmaceutical dosage forms. In the present study, we developed a hollow pH-responsive 3D printed tablet encapsulating drug loaded non-coated and chitosan-coated alginate beads for the targeted colonic delivery of 5-fluorouracil (5-FU). A mixture of Eudragit® L100-55 and Eudragit® S100 was fabricated by means of hot-melt extrusion (HME) and the produced filaments were printed utilizing a fused deposition modeling (FDM) 3D printer to form the pH-responsive layer of the tablet with the rest comprising of a water-insoluble poly-lactic acid (PLA) layer. The filaments and alginate particles were characterized for their physicochemical properties (thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction), their surface topography was visualized by scanning electron microscopy and the filaments' mechanical properties were assessed by instrumented indentation testing and tensile testing. The optimized filament formulation was 3D printed and the structural integrity of the hollow tablet in increasing pH media (pH 1.2 to pH 7.4) was assessed by means of time-lapsed microfocus computed tomography (μCT). In vitro release studies demonstrated controlled release of 5-FU from the alginate beads encapsulated within the hollow pH-sensitive tablet matrix at pH values corresponding to the colonic environment (pH 7.4). The present study highlights the potential of additive manufacturing in fabricating controlled-release dosage forms rendering them pertinent formulations for further in vivo evaluation.
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Wong CY, Al-Salami H, Dass CR. Microparticles, microcapsules and microspheres: A review of recent developments and prospects for oral delivery of insulin. Int J Pharm 2017; 537:223-244. [PMID: 29288095 DOI: 10.1016/j.ijpharm.2017.12.036] [Citation(s) in RCA: 153] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 12/17/2017] [Indexed: 01/02/2023]
Abstract
Diabetes mellitus is a chronic metabolic health disease affecting the homeostasis of blood sugar levels. However, subcutaneous injection of insulin can lead to patient non-compliance, discomfort, pain and local infection. Sub-micron sized drug delivery systems have gained attention in oral delivery of insulin for diabetes treatment. In most of the recent literature, the terms "microparticles" and "nanoparticle" refer to particles where the dimensions of the particle are measured in micrometers and nanometers respectively. For instance, insulin-loaded particles are defined as microparticles with size larger than 1 μm by most of the research groups. The size difference between nanoparticles and microparticles proffers numerous effects on the drug loading efficiency, aggregation, permeability across the biological membranes, cell entry and tissue retention. For instance, microparticulate drug delivery systems have demonstrated a number of advantages including protective effect against enzymatic degradation, enhancement of peptide stability, site-specific and controlled drug release. Compared to nanoparticulate drug delivery systems, microparticulate formulations can facilitate oral absorption of insulin by paracellular, transcellular and lymphatic routes. In this article, we review the current status of microparticles, microcapsules and microspheres for oral administration of insulin. A number of novel techniques including layer-by-layer coating, self-polymerisation of shell, nanocomposite microparticulate drug delivery system seem to be promising for enhancing the oral bioavailability of insulin. This review draws several conclusions for future directions and challenges to be addressed for optimising the properties of microparticulate drug formulations and enhancing their hypoglycaemic effects.
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Affiliation(s)
- Chun Y Wong
- School of Pharmacy and Biomedical Science, Curtin University, Bentley 6102, Australia; Curtin Health Innovation Research Institute, Bentley 6102, Australia
| | - Hani Al-Salami
- School of Pharmacy and Biomedical Science, Curtin University, Bentley 6102, Australia; Curtin Health Innovation Research Institute, Bentley 6102, Australia
| | - Crispin R Dass
- School of Pharmacy and Biomedical Science, Curtin University, Bentley 6102, Australia; Curtin Health Innovation Research Institute, Bentley 6102, Australia.
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6
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Xue W, Chen Y, Chen H, Xia Y. Mechanical properties and drug release of microcapsules containing quaternized-chitosan-modified reduced graphene oxide in the capsular wall. J Appl Polym Sci 2016. [DOI: 10.1002/app.44549] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Wuzi Xue
- School of Materials Science and Engineering; Wuhan University of Technology; Wuhan 430070 China
| | - Yanjun Chen
- School of Materials Science and Engineering; Wuhan University of Technology; Wuhan 430070 China
| | - Hao Chen
- School of Materials Science and Engineering; Wuhan University of Technology; Wuhan 430070 China
| | - Yuanling Xia
- School of Materials Science and Engineering; Wuhan University of Technology; Wuhan 430070 China
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7
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Sen Gupta S, Ghosh M. Synthesis, characterization, stability evaluation and release kinetics of fiber-encapsulated carotene nano-capsules. GRASAS Y ACEITES 2015. [DOI: 10.3989/gya.0226151] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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8
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Sarwar A, Katas H, Samsudin SN, Zin NM. Regioselective Sequential Modification of Chitosan via Azide-Alkyne Click Reaction: Synthesis, Characterization, and Antimicrobial Activity of Chitosan Derivatives and Nanoparticles. PLoS One 2015; 10:e0123084. [PMID: 25928293 PMCID: PMC4415788 DOI: 10.1371/journal.pone.0123084] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Accepted: 02/27/2015] [Indexed: 12/19/2022] Open
Abstract
Recently, the attention of researchers has been drawn toward the synthesis of chitosan derivatives and their nanoparticles with enhanced antimicrobial activities. In this study, chitosan derivatives with different azides and alkyne groups were synthesized using click chemistry, and these were further transformed into nanoparticles by using the ionotropic gelation method. A series of chitosan derivatives was successfully synthesized by regioselective modification of chitosan via an azide-alkyne click reaction. The amino moieties of chitosan were protected during derivatization by pthaloylation and subsequently unblocked at the end to restore their functionality. Nanoparticles of synthesized derivatives were fabricated by ionic gelation to form complexes of polyanionic penta-sodium tripolyphosphate (TPP) and cationic chitosan derivatives. Particle size analysis showed that nanoparticle size ranged from 181.03 ± 12.73 nm to 236.50 ± 14.32 nm and had narrow polydispersity index and positive surface charge. The derivatives and corresponding nanoparticles were evaluated in vitro for antibacterial and antifungal activities against three gram-positive and gram-negative bacteria and three fungal strains, respectively. The minimum inhibitory concentration (MIC) of all derivatives ranged from 31.3 to 250 µg/mL for bacteria and 188 to1500 µg/mL for fungi and was lower than that of native chitosan. The nanoparticles with MIC ranging from 1.56 to 25 µg/mLfor bacteria and 94 to 750 µg/mL for fungi exhibited higher activity than the chitosan derivatives. Chitosan O-(1-methylbenzene) triazolyl carbamate and chitosan O-(1-methyl phenyl sulfide) triazolyl carbamate were the most active against the tested bacterial and fungal strains. The hemolytic assay on erythrocytes and cell viability test on two different cell lines (Chinese hamster lung fibroblast cells V79 and Human hepatic cell line WRL68) demonstrated the safety; suggesting that these derivatives could be used in future medical applications. Chitosan derivatives with triazole functionality, synthesized by Huisgen 1,3-dipolar cycloaddition, and their nanoparticles showed significant enhancement in antibacterial and antifungal activities in comparison to those associated with native, non-altered chitosan.
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Affiliation(s)
- Atif Sarwar
- Centre for Drug Delivery Research, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Kuala Lumpur Campus, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia
| | - Haliza Katas
- Centre for Drug Delivery Research, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Kuala Lumpur Campus, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia
| | - Siti Noradila Samsudin
- Centre for Drug Delivery Research, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Kuala Lumpur Campus, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia
| | - Noraziah Mohamad Zin
- Novel Antibiotic Research Group, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Kuala Lumpur Campus, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia
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9
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Vashist A, Vashist A, Gupta YK, Ahmad S. Recent advances in hydrogel based drug delivery systems for the human body. J Mater Chem B 2014; 2:147-166. [DOI: 10.1039/c3tb21016b] [Citation(s) in RCA: 320] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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10
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Affiliation(s)
- Samaneh Khanlari
- Department of Chemical and Biological Engineering; Centre for Catalysis Research and Innovation; University of Ottawa; 161 Louis Pasteur Pvt. Ottawa ON, Canada K1N 6N5
| | - Marc A. Dubé
- Department of Chemical and Biological Engineering; Centre for Catalysis Research and Innovation; University of Ottawa; 161 Louis Pasteur Pvt. Ottawa ON, Canada K1N 6N5
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11
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Xu R, Feng X, Li W, Xin S, Wang X, Deng H, Xu L. Novel Polymer-Layered Silicate Intercalated Composite Beads for Drug Delivery. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2012; 24:1-14. [DOI: 10.1163/156856211x619630] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Ruifen Xu
- a Key Laboratory of Biomedical Information Engineering of Education Ministry, School of Life Science and Technology, Xi’an Jiaotong University , Xi’an , 710049 , P. R. China
- b Department of Anesthesiology , School of Stomatology, Fourth Military Medical University , Xi’an , 710032 , P. R. China
| | - Xuyang Feng
- c Department of Cardiology , Xijing Hospital, Fourth Military Medical University , Xi’an , 710032 , P. R. China
| | - Wei Li
- d College of Food Science and Technology, Huazhong Agricultural University , No. 1 Shizishan Road, Wuhan , 430070 , P. R. China
| | - Shangjing Xin
- d College of Food Science and Technology, Huazhong Agricultural University , No. 1 Shizishan Road, Wuhan , 430070 , P. R. China
| | - Xiaoying Wang
- e State Key Laboratory of Pulp and Paper Engineering, School of Light Industry and Food, South China University of Technology , Guangzhou , 510640 , P. R. China
| | - Hongbing Deng
- d College of Food Science and Technology, Huazhong Agricultural University , No. 1 Shizishan Road, Wuhan , 430070 , P. R. China
| | - Lixian Xu
- b Department of Anesthesiology , School of Stomatology, Fourth Military Medical University , Xi’an , 710032 , P. R. China
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12
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13
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Sahoo D, Sahoo S, Mohanty P, Sasmal S, Nayak PL. Chitosan: a New Versatile Bio-polymer for Various Applications. Des Monomers Polym 2012. [DOI: 10.1163/138577209x12486896623418] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Debasish Sahoo
- a Institute of Nanobiotechnology, 53/A, Keshpur, Po-CRRI, Cuttack-753006, Orissa, India
| | - Sarmila Sahoo
- b Institute of Nanobiotechnology, 53/A, Keshpur, Po-CRRI, Cuttack-753006, Orissa, India
| | - Priyanka Mohanty
- c Institute of Nanobiotechnology, 53/A, Keshpur, Po-CRRI, Cuttack-753006, Orissa, India
| | - S. Sasmal
- d Central Rice Research Institute, Bidyadharpur, Cuttack-753006, Orissa, India
| | - P. L. Nayak
- e Institute of Nanobiotechnology, 53/A, Keshpur, Po-CRRI, Cuttack-753006, Orissa, India
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14
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Zhang R, Li W, Möhwald H, Sui W, Wang Z, Gao C. Shell modulation by tailoring substituents in chitosan for LbL-assembled microcapsules. J Colloid Interface Sci 2012; 372:40-4. [DOI: 10.1016/j.jcis.2012.01.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 01/09/2012] [Accepted: 01/11/2012] [Indexed: 11/16/2022]
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15
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Zarate J, Virdis L, Orive G, Igartua M, Hernández R, Pedraz J. Design and characterization of calcium alginate microparticles coated with polycations as protein delivery system. J Microencapsul 2011; 28:614-20. [DOI: 10.3109/02652048.2011.599439] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- J. Zarate
- NanoBioCel Group, Laboratory of Pharmaceutics, School of Pharmacy, University of the Basque Country,
Vitoria, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN),
Vitoria, Spain
| | - L. Virdis
- NanoBioCel Group, Laboratory of Pharmaceutics, School of Pharmacy, University of the Basque Country,
Vitoria, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN),
Vitoria, Spain
| | - G. Orive
- NanoBioCel Group, Laboratory of Pharmaceutics, School of Pharmacy, University of the Basque Country,
Vitoria, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN),
Vitoria, Spain
| | - M. Igartua
- NanoBioCel Group, Laboratory of Pharmaceutics, School of Pharmacy, University of the Basque Country,
Vitoria, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN),
Vitoria, Spain
| | - R.M. Hernández
- NanoBioCel Group, Laboratory of Pharmaceutics, School of Pharmacy, University of the Basque Country,
Vitoria, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN),
Vitoria, Spain
| | - J.L. Pedraz
- NanoBioCel Group, Laboratory of Pharmaceutics, School of Pharmacy, University of the Basque Country,
Vitoria, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN),
Vitoria, Spain
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17
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Schellekens RCA, Baltink JH, Woesthuis EM, Stellaard F, Kosterink JGW, Woerdenbag HJ, Frijlink HW. Film coated tablets (ColoPulse technology) for targeted delivery in the lower intestinal tract: influence of the core composition on release characteristics. Pharm Dev Technol 2010; 17:40-7. [PMID: 20923321 DOI: 10.3109/10837450.2010.513986] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The design of a film coating technology which allows a tablet to deliver the drug in the ileocolonic segment would offer new treatment possibilities. The objective is to develop a platform technology that is suitable for a broad range of drug compounds. We developed a coated tablet with a delayed, pulsatile release profile based on a pH-sensitive coating technology (ColoPulse). The production process was validated, and the effect of core composition on the in vitro release and water uptake investigated. The release profile of the standard tablet core composition, based on the use of cellulose as a filler, was independent of the coat thickness in a range of 9.0-13.2 mg/cm(2). The release profile of a coated tablet was strongly influenced when cellulose was partly replaced by the model substance glucose (loss of sigmoidal release), citric acid (stabilization), sodium bicarbonate (destabilization) or sodium benzoate (destabilization). The film coating takes up water when below the pH-threshold. However, this did not cause early disintegration of the coating. The ColoPulse technology is successfully applied on tablets. The in vitro release characteristics of the coated tablets are influenced by the composition of the core.
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Affiliation(s)
- Reinout C A Schellekens
- Department of Hospital and Clinical Pharmacy, University Medical Center Groningen, The Netherlands.
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19
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Bhopatkar D, Anal AK, Stevens WF. Ionotropic alginate beads for controlled intestinal protein delivery: Effect of chitosan and barium counter-ions on entrapment and release. J Microencapsul 2008; 22:91-100. [PMID: 16019894 DOI: 10.1080/02652040400026434] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Alginate beads containing the model protein haemoglobin (Hb) were prepared by coagulation with various counter-ions to improve the controlled release of the protein. The effect of Ba(2+) and Ca(2+) ions and of the polycationic polysaccharide chitosan was investigated. Coagulation with Ba(2+), Ca(2+) and/or chitosan showed differences in the swelling index of the beads, in the encapsulation efficiency of Hb entrapment and in the release of the entrapped protein. Chitosan in the coagulation fluid markedly enhanced the encapsulation efficiency of the Hb. Release studies were conducted in simulated gastric fluid (SGF pH approximately or equal to 1.2) and subsequently in simulated intestinal fluid (SIF ) at 37 degrees C. Beads were stable in the gastric fluid but released their protein upon transfer to intestinal fluid. The release coincides with the burst and disintegration of beads. Rate of protein release from the beads was affected by the Ba(2+) and chitosan concentration in coagulation fluid.
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Affiliation(s)
- D Bhopatkar
- Asian Institute of Technology, Klong Luang, Bangkok, Thailand
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20
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Sodium lauryl sulfate impedes drug release from zinc-crosslinked alginate beads: Switching from enteric coating release into biphasic profiles. Int J Pharm 2008; 350:291-300. [DOI: 10.1016/j.ijpharm.2007.09.010] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2007] [Revised: 08/16/2007] [Accepted: 09/05/2007] [Indexed: 10/22/2022]
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21
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Harish Prashanth K, Tharanathan R. Chitin/chitosan: modifications and their unlimited application potential—an overview. Trends Food Sci Technol 2007. [DOI: 10.1016/j.tifs.2006.10.022] [Citation(s) in RCA: 532] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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22
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Reis CP, Ribeiro AJ, Houng S, Veiga F, Neufeld RJ. Nanoparticulate delivery system for insulin: design, characterization and in vitro/in vivo bioactivity. Eur J Pharm Sci 2007; 30:392-7. [PMID: 17280820 DOI: 10.1016/j.ejps.2006.12.007] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2006] [Revised: 12/21/2006] [Accepted: 12/29/2006] [Indexed: 01/07/2023]
Abstract
Insulin-loaded alginate-dextran nanospheres were prepared by nanoemulsion dispersion followed by triggered in situ gelation. Nanospheres were characterized for mean size and distribution by laser diffraction spectroscopy and for shape by transmission electron microscopy. Insulin encapsulation efficiency and in vitro release were determined by Bradford protein assay and bioactivity determined in vitro using a newly developed Western blot immunoassay and in vivo using Wistar diabetic rats. Nanospheres ranged from 267 nm to 2.76 microm in diameter and demonstrated a unimodal size distribution. Insulin encapsulation efficiency was 82.5%. Alginate-dextran particles suppressed insulin release in acidic media and promoted a sustained release at near neutral conditions. Nanoencapsulated insulin was bioactive, demonstrated through both in vivo and in vitro bioassays.
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MESH Headings
- Alginates/chemistry
- Animals
- Blood Glucose/drug effects
- Blotting, Western
- Cells, Cultured
- Chemistry, Pharmaceutical
- Dextran Sulfate/chemistry
- Diabetes Mellitus, Experimental/blood
- Drug Carriers
- Drug Compounding
- Drug Stability
- Glucuronic Acid/chemistry
- Hexuronic Acids/chemistry
- Hydrogen-Ion Concentration
- Hypoglycemic Agents/administration & dosage
- Hypoglycemic Agents/chemistry
- Hypoglycemic Agents/pharmacology
- Injections, Subcutaneous
- Insulin/administration & dosage
- Insulin/chemistry
- Insulin/pharmacology
- Lasers
- Male
- Microscopy, Electron, Transmission
- Myoblasts/drug effects
- Myoblasts/metabolism
- Nanoparticles
- Particle Size
- Rats
- Rats, Wistar
- Scattering, Radiation
- Solubility
- Technology, Pharmaceutical
- Time Factors
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Affiliation(s)
- Catarina Pinto Reis
- Laboratory of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Rua do Norte, 3000-295 Coimbra, Portugal.
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23
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Reis CP, Ribeiro AJ, Neufeld RJ, Veiga F. Alginate microparticles as novel carrier for oral insulin delivery. Biotechnol Bioeng 2007; 96:977-89. [PMID: 17001630 DOI: 10.1002/bit.21164] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Alginate microparticles produced by emulsification/internal gelation were investigated as a promising carrier for insulin delivery. The procedure involves the dispersion of alginate solution containing insulin protein, into a water immiscible phase. Gelation is triggered in situ by instantaneous release of ionic calcium from carbonate complex via gentle pH adjustment. Particle size is controlled through the emulsification parameters, yielding insulin-loaded microparticles. Particle recovery was compared using several washing protocols. Recovery strategies are proposed and the influence on particle mean size, morphology, recovery yield (RY), encapsulation efficiency, insulin release profile, and structural integrity of released insulin were evaluated. Spherical micron-sized particles loaded with insulin were produced. The recovery process was optimized, improving yield, and ensuring removal of residual oil from the particle surface. The optimum recovery strategy consisted in successive washing with a mixture of acetone/hexane/isopropanol coupled with centrifugation. This strategy led to small spherical particles with an encapsulation efficiency of 80% and a RY around 70%. In vitro release studies showed that alginate itself was not able to suppress insulin release in acidic media; however, this strategy preserves the secondary structure of insulin. Particles had a mean size lower than the critical diameter necessary to be orally absorbed through the intestinal mucosa followed by their passage to systemic circulation and thus can be considered as a promising technology for insulin delivery.
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Affiliation(s)
- Catarina Pinto Reis
- Laboratory of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
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Borges O, Borchard G, Verhoef JC, de Sousa A, Junginger HE. Preparation of coated nanoparticles for a new mucosal vaccine delivery system. Int J Pharm 2006; 299:155-66. [PMID: 15998569 DOI: 10.1016/j.ijpharm.2005.04.037] [Citation(s) in RCA: 173] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2004] [Revised: 04/13/2005] [Accepted: 04/23/2005] [Indexed: 11/20/2022]
Abstract
It has been found that the adsorption of antigens onto chitosan particles is an easy and unique mild loading process suitable to be used with vaccines. In order to increase the stability of this particles and to prevent an immediate desorption in gastrointestinal fluids, a coating process with sodium alginate was developed. One of the challenges of this developing process was to keep the particles in the nanosized range in order to be taken up by M-cells of the Peyer's patches. The observed inversion of the particles' zeta potential values after coating suggested the presence of an alginate coating layer. These results were confirmed by FTIR and DSC techniques. Additionally, in vitro release studies showed that the presence of the alginate layer around the particles was able to prevent a burst release of loaded ovalbumin and to improve the stability of the nanoparticles in simulated intestinal fluid at 37 degrees C. The optimisation of the coating process resulted in 35% (w/w) for the loading capacity of the coated particles. SEM investigations confirmed a suitable size of the coated nanoparticles for the uptake by M-cells.
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Affiliation(s)
- Olga Borges
- Leiden/Amsterdam Center for Drug Research, Division of Pharmaceutical Technology, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
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Wang W, Liu X, Xie Y, Zhang H, Yu W, Xiong Y, Xie W, Ma X. Microencapsulation using natural polysaccharides for drug delivery and cell implantation. ACTA ACUST UNITED AC 2006. [DOI: 10.1039/b603595g] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Adams G, Wang N, Cui Y. Future alternative therapies in a quest to halt aberrations in diabetes mellitus. Biomed Pharmacother 2005; 59:296-301. [PMID: 15939570 DOI: 10.1016/j.biopha.2005.05.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2005] [Indexed: 11/16/2022] Open
Abstract
Under normal physiological conditions, euglycaemia is maintained principally by the homeostatic balance of insulin and glucagon which are secreted from the pancreas. In both type 1 and type 2 diabetes mellitus there is a substantial and chronic increase in the circulating glucose concentration. This elevation in glucose levels is accompanied by a plethora of other biochemical disturbances, including disruption of carbohydrate, fat and protein metabolism. Clinical manifestations of diabetes, which arise from the metabolic disturbances vary between individuals but are often a serious threat to quality and length of life. Pancreas transplantation (Tx) and islet modifications are methods used to restore endogenous insulin secretion in insulin-dependent diabetic patients. In order for this to be achieved successfully, however, some of the problems such as hyperglycemia states (> 150 mg/dl), which may harm pancreatic graft beta cells, immunorejection, the effects of immunosuppression, for example, must be overcome. Considering these problems, therefore, it seems logical that the replacement of the islet tissue itself, either by transplanting a vascularised pancreatic allograft or by transplanting modified pancreatic islet cells, provides a better alternative therapeutic approach than simply replacing insulin that has been lost. This review will show the recent development in the use of pancreatic islets and their modification in a quest to halt the aberrations seen in diabetes mellitus.
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Affiliation(s)
- Gary Adams
- Insulin Diabetes Experimental Research Group, Faculty of Medicine and Health Science, University of Nottingham, Clifton Boulevard, Nottingham NG7 2UH, UK.
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Kumar MNVR, Muzzarelli RAA, Muzzarelli C, Sashiwa H, Domb AJ. Chitosan chemistry and pharmaceutical perspectives. Chem Rev 2005; 104:6017-84. [PMID: 15584695 DOI: 10.1021/cr030441b] [Citation(s) in RCA: 1764] [Impact Index Per Article: 92.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- M N V Ravi Kumar
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research, Sector 67, S. A. S. Nagar, Mohali, Punjab-160 062, India.
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Abstract
Controlled release drug delivery employs drug-encapsulating devices from which therapeutic agents may be released at controlled rates for long periods of time, ranging from days to months. Such systems offer numerous advantages over traditional methods of drug delivery, including tailoring of drug release rates, protection of fragile drugs and increased patient comfort and compliance. Polymeric microspheres are ideal vehicles for many controlled delivery applications due to their ability to encapsulate a variety of drugs, biocompatibility, high bioavailability and sustained drug release characteristics. Research discussed in this review is focused on improving large-scale manufacturing, maintaining drug stability and enhancing control of drug release rates. This paper describes methods of microparticle fabrication and the major factors controlling the release rates of encapsulated drugs. Furthermore, recent advances in the use of polymer microsphere-based systems for delivery of single-shot vaccines, plasmid DNA and therapeutic proteins are discussed, as well as some future directions of microsphere research.
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Affiliation(s)
- Neelesh K Varde
- Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, IL 61801, USA
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Abstract
It has now been conclusively proven that adequate control of blood glucose delays or prevents the progression of diabetic complications. In order to achieve the suggested targets for glycaemic control necessary to reduce the incidence of diabetic complications, it has been established that a more intensive insulin regimen requiring multiple insulin injections is required for patients with type 1 diabetes mellitus. For patients with type 2 diabetes, oral antidiabetic therapy is generally used initially, but given the natural history of type 2 diabetes and the need to achieve improved glycaemic control, earlier use of insulin has been promoted. However, the use of insulin in more intensive regimens for the patient with type 1 diabetes or for earlier treatment of the patient with type 2 diabetes is not routine. Many factors are responsible for this observation. Nevertheless, available device options such as insulin pens or insulin pumps are routinely available for implementation of intensive insulin therapy. However, a major limitation for advancing to intensive insulin therapy is that the only viable way to administer insulin is through injection. Delivery options that use dermal, nasal and oral approaches have been explored. The oral approach may include gastrointestinal, buccal or pulmonary uptake. Recent evidence shows that delivery of insulin via the oral cavity with uptake occurring in the pulmonary alveoli may be the most viable clinical option in the future.
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Affiliation(s)
- William T Cefalu
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, Louisiana 70808, USA.
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Sinha VR, Singla AK, Wadhawan S, Kaushik R, Kumria R, Bansal K, Dhawan S. Chitosan microspheres as a potential carrier for drugs. Int J Pharm 2004; 274:1-33. [PMID: 15072779 DOI: 10.1016/j.ijpharm.2003.12.026] [Citation(s) in RCA: 569] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2002] [Revised: 12/02/2003] [Accepted: 12/12/2003] [Indexed: 11/30/2022]
Abstract
Chitosan is a biodegradable natural polymer with great potential for pharmaceutical applications due to its biocompatibility, high charge density, non-toxicity and mucoadhesion. It has been shown that it not only improves the dissolution of poorly soluble drugs but also exerts a significant effect on fat metabolism in the body. Gel formation can be obtained by interactions of chitosans with low molecular counterions such as polyphosphates, sulphates and crosslinking with glutaraldehyde. This gelling property of chitosan allows a wide range of applications such as coating of pharmaceuticals and food products, gel entrapment of biochemicals, plant embryo, whole cells, microorganism and algae. This review is an insight into the exploitation of the various properties of chitosan to microencapsulate drugs. Various techniques used for preparing chitosan microspheres and evaluation of these microspheres have also been reviewed. This review also includes the factors that affect the entrapment efficiency and release kinetics of drugs from chitosan microspheres.
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Affiliation(s)
- V R Sinha
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh 160014, India.
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Anal AK, Bhopatkar D, Tokura S, Tamura H, Stevens WF. Chitosan-alginate multilayer beads for gastric passage and controlled intestinal release of protein. Drug Dev Ind Pharm 2003; 29:713-24. [PMID: 12889789 DOI: 10.1081/ddc-120021320] [Citation(s) in RCA: 141] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Chitosan-alginate beads loaded with a model protein, bovine serum albumin (BSA) were investigated to explore the temporary protection of protein against acidic and enzymatic degradation during gastric passage. Optimum conditions were established for preparation of homogenous, spherical, and smooth chitosan-alginate beads loaded with BSA. Multilayer beads were prepared by additional treatment with either chitosan or alginate or both. The presence of chitosan in the coagulation bath during bead preparation resulted in increased entrapment of BSA. During incubation in simulated gastric fluid (SGF pH 1.2), the beads showed swelling and started to float but did not show any sign of erosion. Inclusion of pepsin in the gastric fluid did not show a further effect on the properties of the beads. Release studies were done in simulated gastric fluid (SGF pH 1.2) and subsequently in simulated intestinal fluid (SIF pH 7.5) to mimic the physiological gastrointestinal conditions. After transfer to intestinal fluid, the beads were found to erode, burst, and release the protein. Microscopic and macroscopic observations confirmed that the release of protein was brought about by the burst of beads. Chitosan-reinforced calcium-alginate beads showed delay in the release of BSA. The multilayer beads disintegrated very slowly. The enzymes pepsin and pancreatin did not change the characteristics of BSA-loaded chitosan-alginate beads. Single layer chitosan-alginate beads released 80-90% of the model protein within 12h while multilayer beads released only 40-50% in the same period of time. The release from chitosan-alginate beads and multilayer beads in SIF was further delayed without prior incubation in SGF. It is concluded that alginate beads reinforced with chitosan offer an excellent perspective for controlled gastrointestinal passage of protein drugs.
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Affiliation(s)
- Anil K Anal
- Bioprocess Technology Program, Asian Institute of Technology, Klong Luang, Bangkok, Thailand
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Shilpa A, Agrawal SS, Ray AR. Controlled Delivery of Drugs from Alginate Matrix. ACTA ACUST UNITED AC 2003. [DOI: 10.1081/mc-120020160] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
Adequate control of blood sugar has been repeatedly shown to translate into reductions in diabetic complications. Although insulin therapy in patients with type 2 diabetes can achieve and maintain near-normal glycemic goals associated with reductions in microvascular and macrovascular end points, it is often reserved for the later stages of management of these patients because of real or perceived concerns; these include fear and anxiety about worsening diabetes, failure of self-management, loss of quality of life, the pain of self-injection, and the possibility of multiple daily injections. Risks of hypoglycemia, weight gain, and cardiovascular disease may be concerns of physicians, but these risks are either manageable or, in the case of cardiovascular disease, unfounded. Taken together, the barriers to insulin therapy frequently compel physicians to consider it a treatment of last resort. Some of the more common barriers have been addressed through device options such as insulin pens and jet injectors, which may improve convenience but do not alleviate pain and discomfort. Transdermal delivery options using iontophoresis or ultrasound are in early stages of development, but methods based on transmucosal delivery-including buccal, nasal, and pulmonary routes-are further advanced. In particular, recent evidence shows that pulmonary forms of insulin are as safe and effective as rapid-acting injected insulin, and are well accepted by patients even over long-term periods of use. These innovative delivery systems may help overcome the barriers to insulin use.
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Affiliation(s)
- William T Cefalu
- University of Vermont College of Medicine, Burlington, Vermont 05401, USA.
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Shu XZ, Zhu KJ. The release behavior of brilliant blue from calcium-alginate gel beads coated by chitosan: the preparation method effect. Eur J Pharm Biopharm 2002; 53:193-201. [PMID: 11880003 DOI: 10.1016/s0939-6411(01)00247-8] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The aim of this study is to reveal how the release behavior of a model drug (brilliant blue, BB) from chitosan coating calcium-alginate gel beads (CCAGB) was influenced by the preparation methods. The CCAGB were prepared by dropping alginate solution into CaCl(2)/chitosan solution (method 1(a)), or into chitosan solution then gelled by CaCl(2) (method 1(b)), or into CaCl(2) solution then coated by chitosan (method 2). Scanning electron microscopy was used for morphology observation, and elemental analysis was applied to determine the chitosan content bound on calcium-alginate gel beads (CAGB). Compared to CAGB, the dried CCAGB had poorer shape and rougher surface morphology especially in methods 1(a) and (b); moreover, CCAGB was found to be more instable in 0.9% NaCl and serious burst of beads occurred when high concentration of alginate (3.0 and 5.0% w/v) was used. The influence on BB release from the beads by chitosan coating was not only related to the chitosan density on bead surface, but also preparation method and other factors. Under un-dried bead state in method 1(a), the increase of chitosan content prolonged BB release in 0.9% (w/v) NaCl; while in method 2, the increase of chitosan concentration over 0.1% (w/v) (3.0% (w/v) alginate concentration was used) resulted in more serious burst of beads and hence facilitated BB release. Furthermore, in both methods 1(a) and 2, the increase of alginate from 1.5 to 3.0 or 5.0% (w/v) usually resulted in the significant burst of beads and accelerated BB release when 0.3 or 0.5% (w/v) chitosan was used for coating. Drying process greatly influenced BB release profile due to the destroying of alginate-chitosan film. The acceleration of BB release from CCAGB by drying process was more significant in the case of method 1 than of method 2.
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Affiliation(s)
- X Z Shu
- Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, People's Republic of China
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Dornish M, Kaplan D, Skaugrud O. Standards and guidelines for biopolymers in tissue-engineered medical products: ASTM alginate and chitosan standard guides. American Society for Testing and Materials. Ann N Y Acad Sci 2001; 944:388-97. [PMID: 11797688 DOI: 10.1111/j.1749-6632.2001.tb03850.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The American Society for Testing and Materials (ASTM) is making a concerted effort to establish standards and guidelines for the entire field of tissue-engineered medical products (TEMPS). Safety, consistency, and functionality of biomaterials used as matrices, scaffolds, and immobilizing agents in TEMPS are a concern. Therefore, the ASTM has established a number of task groups to produce standards and guidelines for such biomaterials. Alginate is a naturally occurring biomaterial used for immobilizing living cells to form an artificial organ, such as encapsulated pancreatic islets. In order to aid in successful clinical applications and to help expedite regulatory approval, the alginate used must be fully documented. The ASTM alginate guide gives information on selection of testing methodologies and safety criteria. Critical parameters such as monomer content, molecular weight, and viscosity, in addition to more general parameters, such as dry matter content, heavy metal content, bioburden, and endotoxin content are described in the ASTM document. In a like manner, the characterization parameters for chitosan, a bioadhesive polycationic polysaccharide, are described in a separate guide. For chitosan, the degree of deacetylation is of critical importance. Control of protein content and, hence, potential for hypersensitivity, endotoxin content, and total bioburden are important in chitosan preparations for TEMPS. Together these two guides represent part of the effort on behalf of the ASTM and other interested parties to ensure quality and standardization in TEMPS.
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Affiliation(s)
- M Dornish
- Pronova Biomedical a.s, Oslo, Norway.
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Literature alerts. J Microencapsul 2000; 17:117-25. [PMID: 10702047 DOI: 10.1080/026520400288607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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