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Li H, Wang J, Xu Q, Tian S, Yang W. Design and Evaluation of Glimepiride Hydrogel for Transdermal Delivery. Drug Dev Ind Pharm 2022; 48:397-405. [PMID: 36048002 DOI: 10.1080/03639045.2022.2120493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The solubility of glimepiride (GM) was improved from 1.6 μg/mL to 22.0 mg/mL when GM and meglumine (MU) complexes were prepared. Therefore, transdermal hydrogels of GM Carbopol (GM-CP) and GM hydroxypropyl methylcellulose pullulan (GM-HPMC-Pu) were prepared successfully utilizing the improved drug solubility by GM-MU. Based on single factor experiment and response surface methodology, two kinds of hydrogel formulations were optimized by drug release studies in vitro. The optimized GM-CP hydrogel was composed of GM, the mixture of azone and oleic acid (1:1, 2.6%, v/v) and carbopol 940 (1%, w/v). The GM-HPMC-Pu hydrogel was developed using GM, HPMC (3.5%, w/v), Pu (1.5%, w/v), glycerol (5%, v/v), azone (2.9%, v/v) and oleic acid (2.6%, v/v). The study of hydrogels in vivo was performed using rabbits. The results indicated that the drug could sustain release from GM-CP or GM-HPMC-Pu hydrogel and maintain the high plasma concentration for 48 h. Compared with commercial GM tablet, the relative bioavailability of GM-CP and GM-HPMC-Pu hydrogel reached up 48% and 133%, respectively. Moreover, the drug release in vitro could well predict its absorption in vivo. There was a good correlation (R2 ≥0.966) in GM hydrogel between the drug release in vitro and transdermal absorption in vivo. Therefore, a novel GM hydrogel dosage form may be considered to design.
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Affiliation(s)
- Haiying Li
- College of Pharmaceutical Sciences & Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Hebei University, Baoding 071002, PR China
| | - Jiajia Wang
- College of Pharmaceutical Sciences & Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Hebei University, Baoding 071002, PR China
| | - Qianru Xu
- College of Pharmaceutical Sciences & Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Hebei University, Baoding 071002, PR China
| | - Shuya Tian
- College of Pharmaceutical Sciences & Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Hebei University, Baoding 071002, PR China
| | - Wenzhi Yang
- College of Pharmaceutical Sciences & Key Laboratory of Pharmaceutical Quality Control of Hebei Province, Hebei University, Baoding 071002, PR China
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2
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Timergalieva VR, Gennari CGM, Cilurzo F, Moustafine RI. Interpolyelectrolyte complexes based on Carbopol and oppositely charged polymer as new carriers for oral controlled diclofenac delivery. POLYM ADVAN TECHNOL 2021. [DOI: 10.1002/pat.5256] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | | | - Francesco Cilurzo
- Department of Pharmaceutical Science University of Milan Milan Italy
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3
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Abstract
Abstract
The review presents current research results for Carbopol-based microgels as yield-stress materials, covering three aspects: chemical, physical and rheological. Such a joint three-aspect study has no analog in the literature. The chemical aspects of Carbopol polymers are presented in terms of a cross-linking polymerization of acrylic acid, their molecular structure, microgel formulation, polyacid dissociation and neutralization, osmotic pressure and associated immense microgel swelling. The physical characterization is focused on models of the shear-induced solid-to-liquid transition of microgels, which are formed of mesoscopic particles typical for soft matter materials. Models that describe interparticle effects are presented to explain the energy states of microgel particles at the mesoscale of scrutiny. Typical representatives of the models utilize attributes of jamming dispersions, micromechanical and polyelectrolyte reactions. Selected relationships that result from the models, such as scaling rules and nondimensional flow characteristics are also presented. The rheological part presents the discussion of problems of yield stress in 2D and 3D deformations, appearance and magnitude of the wall slip. The theory and characteristics of Carbopol microgel deformation in rotational rheometers are presented with graphs for the steady-state measurements, stress-controlled oscillation and two types of transient shear deformation. The review is concluded with suggestions for future research.
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Affiliation(s)
- Zdzisław Jaworski
- Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology , Aleja Piastow 42 , 71-065 , Szczecin , Poland
| | - Tadeusz Spychaj
- Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology , Aleja Piastow 42 , 71-065 , Szczecin , Poland
| | - Anna Story
- Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology , Aleja Piastow 42 , 71-065 , Szczecin , Poland
| | - Grzegorz Story
- Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology , Aleja Piastow 42 , 71-065 , Szczecin , Poland
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Ibrahim M, Naguib YW, Sarhan HA, Abdelkader H. Preformulation-Assisted Design and Characterization of Modified Release Gastroretentive Floating Extrudates Towards Improved Bioavailability and Minimized Side Effects of Baclofen. J Pharm Sci 2020; 110:1227-1239. [PMID: 33069710 DOI: 10.1016/j.xphs.2020.10.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/07/2020] [Accepted: 10/12/2020] [Indexed: 12/01/2022]
Abstract
Baclofen immediate release mode of administration exhibit sharp plasma peaking that results in the emergence of side effects like hypotension. This research employs preformulation studies to design an optimum dosage form for baclofen to enhance therapeutic outcomes. These studies include partition coefficient and ex-vivo permeation studies. Partition coefficient was found to be 1.27 at pH 7.4. Permeation studies confirmed the presence of specialized transport mechanism through the GIT. It was concluded that an ideal formulation of baclofen should provide slow-release of the drug to avoid sharp peaking. Modified-release floating extrudates of baclofen were prepared using Carbopol 934 and HPMC with different gas-forming agents. Different release-retarding materials (Eudragit L100, Eudragit RS100 and Cetyl alcohol) were used as ingredients in the binder solutions. The prepared extrudates were assessed for their drug content, floating ability, friability properties and in vitro release properties. The prepared extrudates recorded buoyance characteristics for 24 h with a floating lag time varying from 0 to 73.34 s. The optimized extrudates manifested extended baclofen release for up to 8 h compared to 0.2 h for marketed baclofen tablets. This approach was found efficient to provide greater bioavailability and minimize hypotension associated with commercial baclofen tablets.
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Affiliation(s)
- Mohamed Ibrahim
- Department of Pharmaceutics, Faculty of Pharmacy, Minia University, Minia, Egypt
| | - Youssef W Naguib
- Department of Pharmaceutics, Faculty of Pharmacy, Minia University, Minia, Egypt
| | - Hatem A Sarhan
- Department of Pharmaceutics, Faculty of Pharmacy, Minia University, Minia, Egypt
| | - Hamdy Abdelkader
- Department of Pharmaceutics, Faculty of Pharmacy, Minia University, Minia, Egypt; Department of Pharmaceutics, Faculty of Pharmacy, Deraya University, New Minia City, Minia, Egypt.
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5
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Géraud B, Jørgensen L, Ybert C, Delanoë-Ayari H, Barentin C. Structural and cooperative length scales in polymer gels. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2017; 40:5. [PMID: 28097479 DOI: 10.1140/epje/i2017-11490-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 12/01/2016] [Indexed: 06/06/2023]
Abstract
Understanding the relationship between the material structural details, the geometrical confining constraints, the local dynamical events and the global rheological response is at the core of present investigations on complex fluid properties. In the present article, this problem is addressed on a model yield stress fluid made of highly entangled polymer gels of Carbopol which follows at the macroscopic scale the well-known Herschel-Bulkley rheological law. First, performing local rheology measurements up to high shear rates ([Formula: see text] s-1)and under confinement, we evidence unambiguously the breakdown of bulk rheology associated with cooperative processes under flow. Moreover, we show that these behaviors are fully captured with a unique cooperativity length [Formula: see text] over the whole range of experimental conditions. Second, we introduce an original optical microscopy method to access structural properties of the entangled polymer gel in the direct space. Performing image correlation spectroscopy of fluorophore-loaded gels, the characteristic size D of carbopol gels microstructure is determined as a function of preparation protocol. Combining both dynamical and structural information shows that the measured cooperative length [Formula: see text] corresponds to 2-5 times the underlying structural size D, thus providing a strong grounding to the "Shear Transformation Zones" modeling approach.
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Affiliation(s)
- Baudouin Géraud
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, VILLEURBANNE, France
| | - Loren Jørgensen
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, VILLEURBANNE, France
| | - Christophe Ybert
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, VILLEURBANNE, France
| | - Hélène Delanoë-Ayari
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, VILLEURBANNE, France
| | - Catherine Barentin
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, F-69622, VILLEURBANNE, France.
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6
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Patel P, Madan P, Lin S. Formulation and evaluation of time-controlled triple-concentric mefenamic acid tablets for rheumatoid arthritis. Pharm Dev Technol 2014; 19:355-62. [PMID: 23611159 DOI: 10.3109/10837450.2013.788514] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A triple-concentric time-controlled release mefenamic acid (MA) tablet was developed using Carbopol and Ethocel polymers. The burst dose was programed to release immediately after an ingestion of tablet to be followed by a lag period of 2-4 h, and thereafter an 8 h controlled release of MA from core tablet. Core tablets were prepared using Carbopols 971P, 974P, 71G or 907 at various concentrations. The core tablet provided a controlled release of MA and the release rate decreased with increasing polymer concentration. Highly cross-linked Carbopol 974P released MA at a faster rate compared to release from Carbopol 971P with medium degree of cross-linking. Carbopols 71G and 971P exhibited essentially similar release rates. Carbopol 907, a linear polymer, showed fastest release of MA. The extent of uptake of dissolution medium by core tablets was inversely related to the rate of release of MA from the tablets. Compression coating of core tablet with Ethocel provided the lag period to delay release of MA from core tablet. Increase in lateral coating thickness decreased MA release and increased lag period. Compression forces applied during compression coating with Ethocel for lag period, and immediate-release MA coating for burst release did not affect the integrity of core tablet.
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Affiliation(s)
- Pooja Patel
- College of Pharmacy and Health Sciences, St. John's University , Queens, NY , USA
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Abdelbary A, El-Gendy NA, Hosny A. Microencapsulation Approach for Orally Extended Delivery of Glipizide: In vitro and in vivo Evaluation. Indian J Pharm Sci 2013; 74:319-30. [PMID: 23626387 PMCID: PMC3630727 DOI: 10.4103/0250-474x.107063] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Revised: 08/14/2012] [Accepted: 08/24/2012] [Indexed: 11/25/2022] Open
Abstract
Glipizide is an effective antidiabetic agent, however, it suffers from relatively short biological half-life. To solve this encumbrance, it is a prospective candidate for fabricating glipizide extended release microcapsules. Microencapsulation of glipizde with a coat of alginate alone or in combination with chitosan or carbomer 934P was prepared employing ionotropic gelation process. The prepared microcapsules were evaluated in vitro by microscopical examination, determination of the particle size, yield and microencapsulation efficiency. The filled capsules were assessed for content uniformity and drug release characteristics. Stability study of the optimised formulas was carried out at three different temperatures over 12 weeks. In vivo bioavailability study and hypoglycemic activity of C9 microcapsules were done on albino rabbits. All formulas achieved high yield, microencapsulation efficiency and extended t1/2. C9 and C19 microcapsules attained the most optimised results in all tests and complied with the dissolution requirements for extended release dosage forms. These two formulas were selected for stability studies. C9 exhibited longer shelf-life and hence was chosen for in vivo studies. C9 microcapsules showed an improvement in the drug bioavailability and significant hypoglycemic activity compared to immediate release tablets (Minidiab® 5 mg). The optimised microcapsule formulation developed was found to produce extended antidiabetic activity.
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Affiliation(s)
- A Abdelbary
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Cairo-11562, Egypt
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Mudhivarthi VK, Cole KS, Novak MJ, Kipphut W, Deshapriya IK, Zhou Y, Kasi RM, Kumar CV. Ultra-stable hemoglobin–poly(acrylic acid) conjugates. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm34434c] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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9
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Thilakarathne V, Briand VA, Zhou Y, Kasi RM, Kumar CV. Protein polymer conjugates: improving the stability of hemoglobin with poly(acrylic acid). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:7663-7671. [PMID: 21591719 DOI: 10.1021/la2015034] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The synthesis, characterization, and evaluation of a novel polymer-protein conjugate are reported here. The covalent conjugation of high-molecular weight poly(acrylic acid) (PAA) to the lysine amino groups of met-hemoglobin (Hb) resulted in the covalent conjugation of Hb to PAA (Hb-PAA conjugate), as confirmed by dialysis and electrophoresis studies. The retention of native-like structure of Hb in Hb-PAA was established from Soret absorption, circular dichroism studies, and the redox activity of the iron center in Hb-PAA. The peroxidase-like activities of the Hb-PAA conjugate further confirmed the retention of Hb structure and biological activity. Thermal denaturation of the conjugate was investigated by differential scanning calorimetry and steam sterilization studies. The Hb-PAA conjugate indicated an improved denaturation temperature (T(d)) when compared to that of the unmodified Hb. One astonishing observation was that polymer conjugation significantly enhanced the Hb-PAA storage stability at room temperature. After 120 h of storage at room temperature in phosphate-buffered saline (PBS) at pH 7.4, for example, Hb-PAA retained 90% of its initial activity and unmodified Hb retained <60% of its original activity under identical conditions of buffer, pH, and temperature. Our conjugate demonstrates the key role of polymers in enhancing Hb stability via a very simple, efficient, general route. Water-swollen, lightly cross-linked, stable Hb-polymer nanogels of 100-200 nm were produced quickly and economically by this approach for a wide variety of applications.
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Affiliation(s)
- Vindya Thilakarathne
- Department of Chemistry, U-3060, University of Connecticut, Storrs, Connecticut 06269-3060, USA
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10
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Karn PR, Vanić Z, Pepić I, Škalko-Basnet N. Mucoadhesive liposomal delivery systems: the choice of coating material. Drug Dev Ind Pharm 2010; 37:482-8. [DOI: 10.3109/03639045.2010.523425] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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11
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Dodou D, Breedveld P, Wieringa PA. Friction manipulation for intestinal locomotion. MINIM INVASIV THER 2009; 14:188-97. [PMID: 16754162 DOI: 10.1080/13645700510033985] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The importance of colonoscopies on the one hand and the drawbacks of the conventional instrumentation on the other have led to research into alternative colonoscopic devices. The main question for the development of such devices is the method of locomotion along the slippery and flaccid intestinal tube. This paper suggests a new intestinal locomotion method based on friction manipulation between the device and the intestinal wall. A new concept to manipulate friction is described. The concept is based on the active alterations of the friction between the device and the intestinal wall and it is inspired by the locomotion of biological species such as snails and starfish.
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Affiliation(s)
- Dimitra Dodou
- Man-Machine Systems Group, Faculty of Mechanical, Maritime and Material Engineering, Delft University of Technology, Delft, The Netherlands
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12
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Gad HA, El-Nabarawi MA, Abd El-Hady SS. Formulation and Evaluation of Secnidazole or Doxycycline Dento-Oral Gels. Drug Dev Ind Pharm 2008; 34:1356-67. [DOI: 10.1080/03639040802122944] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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13
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Qussi B, Suess WG. Investigation of the Effect of Various Shellac Coating Compositions Containing Different Water-Soluble Polymers on In Vitro Drug Release. Drug Dev Ind Pharm 2008; 31:99-108. [PMID: 15704861 DOI: 10.1081/ddc-44226] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In this study drug pellets were coated with aqueous shellac coating formulations containing different amounts of polyvinyl alcohol (PVA), hydroxypropyl methylcellulose (HPMC), and carbomer 940. The coating level needed for enteric coating was determined. The influence of different amounts of PVA, HPMC, and carbomer on drug release and mechanism; the porosity, and the stability of shellac coatings was investigated. The results show that the incorporation of different concentrations of HPMC into shellac coatings, due to the increasing of pores, could considerably increase the drug release from the pellets in purified water. Moreover, the swelling effect of carbomer 940 leads to much more diffusivity through shellac coatings in water. In addition, PVA results in small cracking in the films and much more diffusion of drug in water. Furthermore, all coating systems containing different hydrophilic polymers that were used in the present work could prevent the dissolution of drug in simulated gastric juice for 2 hours. On the other hand, a rapid and complete release of drug within 45 minutes was observed in simulated intestinal fluid. Drug release from shellac coated pellets and ones containing different amounts of carbomer was affected between 3-6 months, whereas shellac coatings containing different amounts of PVA or HPMC show the same dissolution profiles with small deviation after 12 months.
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Affiliation(s)
- Basel Qussi
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Leipzig, Leipzig, Germany
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Qussi B, Suess WG. The Influence of Different Plasticizers and Polymers on the Mechanical and Thermal Properties, Porosity and Drug Permeability of Free Shellac Films. Drug Dev Ind Pharm 2008; 32:403-12. [PMID: 16638678 DOI: 10.1080/03639040600559099] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The effect of triethyl citrate (TEC) and different molecular weights and concentrations of polyethylene glycol (PEG), in addition to the effect of different water-soluble polymers and dispersions at different levels, hydroxypropyl methylcellulose (HPMC), methylcellulose (MC), carbomer 940, polyvinyl alcohol (PVA), ethyl cellulose (EC), on the mechanical and thermal properties, drug permeability, and porosity of free shellac films were investigated. Shellac films were cast from aqueous solutions, and their mechanical properties were studied by tensile test. Thermal analyses were performed using differential scanning calorimetry (DSC). The results showed that the addition of plasticizer caused a decrease in both elastic modulus and glass transition temperature (T(g)) and an increase in elongation at break of free shellac films. This effect was related to the concentrations of plasticizers. Different molecular weights of PEGs have different plasticization mechanisms.Moreover, the incorporation of different amounts of HPMC, MC, or carbomer in free shellac films caused an increase in the flexibility, decrease in T(g), and a marked increase in drug permeability of free shellac films, whereas the addition of PVA caused a decrease in flexibility and drug permeability and an increase in T(g). Addition of EC resulted in a slight decrease of the elasticity and a small decrease in drug permeability. However it does not show a considerable effect on the T(g). In addition, it was found that the drug permeability is directly related to the mechanical properties and T(g) of shellac films.
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Affiliation(s)
- Basel Qussi
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Leipzig, Leipzig, Germany
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15
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Makhlof A, Werle M, Takeuchi H. Mucoadhesive drug carriers and polymers for effective drug delivery. J Drug Deliv Sci Technol 2008. [DOI: 10.1016/s1773-2247(08)50075-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Abstract
The main challenge in designing diagnostic devices able to move along the colon is their locomotion method. Manipulating friction with the colonic surface is a key requirement for their safe and atraumatic propagation. One possible solution is to generate friction by means of adhesive forces. For this purpose, a diagnostic device can be covered with mucoadhesive films that stick to the mucus layer of the colonic surface and generate high static friction. This paper investigates whether micropatterning the mucoadhesive films is able to enhance the grip with the colonic surface even more than flat mucoadhesive films. This idea is inspired by the sponge-form adhesive secretion of sea stars which is released by numerous tubular feet. Experiments in vitro showed that the frictional performance of mucoadhesive micropatterns exceed that of non-patterned mucoadhesive films. Moreover, the grip achieved by mucoadhesive micropatterns is far higher than the grip generated by non-mucoadhesive micropatterns made of an elastomeric material. Mucoadhesive micropatterned films also avoid the risk of damaging the colonic surface, since they interact only with the mucus layer and leave the colonic epithelium unaffected.
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Affiliation(s)
- Dimitra Dodou
- Department Arzt, Max-Planck-Institut fuer Metallforschung, Heisenbergstrasse 3, 70569 Stuttgart, Germany.
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17
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Abstract
The main challenge in designing diagnostic devices able to move along the colon is their locomotion method. Manipulating friction with the colonic surface is a key requirement for their safe and atraumatic propagation. One possible solution is to generate friction by means of adhesive forces. For this reason, a diagnostic device can be covered with mucoadhesive films that are able to stick on the colonic surface by generating high static friction. For a smooth transition from static to dynamic regime, the mucoadhesive films should unstick just before the initialisation of motion. Experiments have shown that promoting cohesive fracture of the films by controllable air introduction does not lead to friction reduction sufficient for smooth unsticking. Introducing water at the film-colon interface, however, reduces the static friction significantly, and makes the device to unstick and slide smoothly without leaving film fragments on the colonic surface behind. If unsticking is initiated by means of air or water introduction, a new film is required each time the device is required to restick. As an alternative, the possibility of coating the device with environmentally-sensitive mucoadhesive polymers that can respond reversibly to external stimuli and alter their properties is discussed.
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Affiliation(s)
- Dimitra Dodou
- Department of Bio-Mechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, Delft, The Netherlands.
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Taş C, Ozkan Y, Savaşer A, Baykara T. In Vitro and Ex Vivo Permeation Studies of Chlorpheniramine Maleate Gels Prepared by Carbomer Derivatives. Drug Dev Ind Pharm 2004; 30:637-47. [PMID: 15285337 DOI: 10.1081/ddc-120037665] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The antihistaminic chlorpheniramine maleate (CPM) is used for symptomatic relief of hypersensitivity reactions and in pruritic skin disorders. At present, the drug is marketed in tablet, capsule, syrup, cream, and injectable dosage forms. Chlorpheniramine maleate has some side effects when taken orally. Due to its first pass effect, only 25%-45% of the orally administered dose reaches the blood circulation. To bypass these disadvantages, we aimed to investigate percutaneous absorption of CPM from gel formulations prepared with different carbomer derivatives (Carbopol 934, 940, 941, 2984, 980, and 981; main differences are related to presence of a comonomer and cross-link density). Cellulose membrane was used as the diffusion barrier for all the formulations' drug-release studies. The release of active substance from carbopol derivatives, which have the least cross-linking density (Carbopol 941 and 981) was found to be numerically higher than the others. The formulation (F8; 1% Carbopol 941) that exhibited the maximum drug release through the cellulose membrane was further studied for drug release by using polyurethane membrane, excised rat skin, and human skin. The penetration of the active substance through different diffusion barriers was found to be statistically different (p<0.05) when compared. Of all the different diffusion barriers, rat skin gave the closest results to human skin. Thus topical application of CPM in the carbomer gel may be of potential use for local activity. The type and concentration of carbomers can affect drug release. The synthetic membranes are useful in assessments of formulations in quality assurance but they do not give definite indication of how a formulation will behave when it is used on skin.
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Affiliation(s)
- Cetin Taş
- Department of Pharmaceutical Technology, Gülhane Military Medical Academy, Etlik, Ankara, Turkey
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Wang LF, Chen WB, Chen TY, Lu SC. Effects of the preparation methods of hydroxypropyl methylcellulose/polyacrylic acid blended films on drug release. JOURNAL OF BIOMATERIALS SCIENCE. POLYMER EDITION 2003; 14:27-44. [PMID: 12635769 DOI: 10.1163/15685620360511128] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Hydroxypropyl methylcellulose (HPMC)/polyacrylic acid (PAA) blended films were prepared under different conditions (i.e. temperature, solvent, and cross-linking agent). The effects of hydrogen-bonding interactions or a chemical reaction between the two-component polymers in the blended films on drug release were studied. Two model drugs were used for comparison: a water-soluble drug, dl-propranolol hydrochloride, and a lipophilic drug, ketoprofen. The H-bonding interaction of HPMC/PAA was found to be stronger in the blended films prepared from H2O than that from H2O/EtOH. However, the H-bonding effect between HPMC and PAA on drug release is indistinct. Chemical esterification of the carboxylic acid groups of PAA with the hydroxyl groups of HPMC was proposed from the solid-state NMR, ESCA, and FTIR studies when the blended films were dried at 110 degrees C. This chemical reaction also resulted in insolubilization of the blended films.
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Affiliation(s)
- Li-Fang Wang
- School of Chemistry, Kaohsiung Medical University, 100 Shih-Chun 1st Road, Kaohsiung City 80708, Taiwan.
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20
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Abstract
AIM: To study the bioadhesive property of carbomer934 in dog alimentary tract.
METHODS: Carbomer934 and ethylcellulose were radiolabelled with technetium-99 m; and Gastrointestinal emptying rate of materials was measured using the technique of gamma scintigraphy.
RESULTS: After oral administration, the maximum intestinal radioactivity of non-bioadhesive granules and bioadhesive granules were observed in the second hour and the sixth hour respectively. Constants of stomach emptying rate of nonadhesive granules, bioadhesive granulesI and bioadhesive granulesII were 0.774 h-1,0.265 h-1 and 0.321 h-1 respectively on the base of gastric residual amount. Compared to nonadhesive material (ethylcellulose), the migration rate of adhesive material(carbomer934) was remarkably slower in dog alimentary canal.
CONCLUSION: It is concluded that, in the dog, interactions between gastrointestinal mucus layer and adhesive material or nonadhesive material were significantly different. Carbomer934 had stronger in vivo bioadhesive property than ethylcellulose.
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Affiliation(s)
- Jie Fu
- West China School of Pharmacy, Sichuan University.Chengdu, 610041, China
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