1
|
Behera SK, Mohapatra M. Exploring the interaction of dietary fiber hydroxypropyl methylcellulose and biosurfactant sodium deoxycholate. Colloid Polym Sci 2022. [DOI: 10.1007/s00396-022-05025-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
2
|
Patel RK, Jonnalagadda S, Gupta PK. Use of Flory-Huggins Interaction Parameter and Contact Angle Values to Predict the Suitability of the Drug-Polymer System for the Production and Stability of Nanosuspensions. Pharm Res 2022; 39:1001-1017. [PMID: 35505262 DOI: 10.1007/s11095-022-03269-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 04/21/2022] [Indexed: 11/30/2022]
Abstract
PURPOSE Use of Flory-Huggins interaction parameter and contact angle values to predict the suitability of the drug-polymer system for the production and stability of nanosuspensions. MATERIAL AND METHODS Melting point depression of the drug was measured using differential scanning calorimetry. Interaction parameter, χ, was calculated using the melting point depression data to elucidate the drug-polymer interaction strength to predict the suitability of the drug-polymer system for the production and stability of nanosuspensions. Contact angle of the drug films were measured with purified water and 0.1%w/w polymer solutions to predict polymer's suitability for the production and stability of nanosuspension. Nanosuspensions were manufactured to validate the application of the melting point depression approach along with surface property information. RESULTS All three polymers, HPMC, Soluplus®, and poloxamer exhibited a negative interaction parameter with naproxen and budesonide. Higher negative interaction parameter values for the naproxen-polymer system indicated stronger drug-polymer interactions, while smaller negative interaction parameter values for the budesonide-polymer system indicated weaker drug-polymer interactions. Interaction parameter was not obtained for fenofibrate with HPMC and Soluplus®, and similarly, no interaction parameter was obtained for carvedilol with HPMC, most likely due to weaker drug-polymer interactions. All three polymers provided lower equilibrium contact angle values when compared to purified water, indicating an affinity for polymers. CONCLUSIONS Successful production and stability of several nanosuspensions were correlated with Flory-Huggins's interaction parameter and contact angle values. In the absence of melting point depression, contact angle values can also be used predict the agglomeration tendencies as we have shown for this study.
Collapse
Affiliation(s)
- Rakesh K Patel
- University of the Sciences in Philadelphia, 600 S 43rd Street, Philadelphia, PA, 19104, USA.
| | | | - Pardeep K Gupta
- University of the Sciences in Philadelphia, 600 S 43rd Street, Philadelphia, PA, 19104, USA
| |
Collapse
|
3
|
Impact of polymers on the aggregation of wet-milled itraconazole particles and their dissolution from spray-dried nanocomposites. ADV POWDER TECHNOL 2018. [DOI: 10.1016/j.apt.2018.09.039] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
4
|
Impact of dispersants on dissolution of itraconazole from drug-loaded, surfactant-free, spray-dried nanocomposites. POWDER TECHNOL 2018. [DOI: 10.1016/j.powtec.2018.08.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
5
|
Premathasan N, Taylor SE. Viscometric analysis of the hydration of a surface cross-linked EM-HEC polymer. Eur Polym J 2018. [DOI: 10.1016/j.eurpolymj.2018.03.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
6
|
Teruya K, Oguma A, Nishizawa K, Kamitakahara H, Doh-ura K. Pyrene conjugation and spectroscopic analysis of hydroxypropyl methylcellulose compounds successfully demonstrated a local dielectric difference associated with in vivo anti-prion activity. PLoS One 2017; 12:e0185357. [PMID: 28934337 PMCID: PMC5608368 DOI: 10.1371/journal.pone.0185357] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 09/11/2017] [Indexed: 11/18/2022] Open
Abstract
Our previous study on prion-infected rodents revealed that hydroxypropyl methylcellulose compounds (HPMCs) with different molecular weights but similar composition and degree of substitution have different levels of long-lasting anti-prion activity. In this study, we searched these HPMCs for a parameter specifically associated with in vivo anti-prion activity by analyzing in vitro chemical properties and in vivo tissue distributions. Infrared spectroscopic and thermal analyses revealed no differences among HPMCs, whereas pyrene conjugation and spectroscopic analysis revealed that the fluorescence intensity ratio of peak III/peak I correlated with anti-prion activity. This correlation was more clearly demonstrated in the anti-prion activity of the 1-year pre-infection treatment than that of the immediate post-infection treatment. In addition, the intensity ratio of peak III/peak I negatively correlated with the macrophage uptake level of HPMCs in our previous study. However, the in vivo distribution pattern was apparently not associated with anti-prion activity and was different in the representative tissues. These findings suggest that pyrene conjugation and spectroscopic analysis are powerful methods to successfully demonstrate local dielectric differences in HPMCs and provide a feasible parameter denoting the long-lasting anti-prion activity of HPMCs in vivo.
Collapse
Affiliation(s)
- Kenta Teruya
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Ayumi Oguma
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Keiko Nishizawa
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Hiroshi Kamitakahara
- Division of Forest and Biomaterials Science, Kyoto University Graduate School of Agriculture, Kyoto, Kyoto, Japan
| | - Katsumi Doh-ura
- Department of Neurochemistry, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- * E-mail:
| |
Collapse
|
7
|
Patel SG, Bummer PM. Thermodynamics of aggregate formation between a non-ionic polymer and ionic surfactants: An isothermal titration calorimetric study. Int J Pharm 2016; 516:131-143. [PMID: 27789368 DOI: 10.1016/j.ijpharm.2016.10.053] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 10/13/2016] [Accepted: 10/23/2016] [Indexed: 10/20/2022]
Abstract
This report examines the energetics of aggregate formation between hydroxypropyl methylcellulose (HPMC) and model ionic surfactants including sodium dodecyl sulfate (SDS) at pharmaceutically relevant concentrations using the isothermal titration calorimetry (ITC) technique and a novel treatment of calorimetric data that accounts for the various species formed. The influence of molecular weight of HPMC, temperature and ionic strength of solution on the aggregate formation process was explored. The interaction between SDS and HPMC was determined to be an endothermic process and initiated at a critical aggregation concentration (CAC). The SDS-HPMC interactions were observed to be cooperative in nature and dependent on temperature and ionic strength of the solution. Molecular weight of HPMC significantly shifted the interaction parameters between HPMC and SDS such that at the highest molecular weight (HPMC K-100M;>240kDa), although the general shape of the titration curve (enthalpogram) was observed to remain similar, the critical concentration parameters (CAC, polymer saturation concentration (Csat) and critical micelle concentration (CMC)) were significantly altered and shifted to lower concentrations of SDS. Ionic strength was also observed to influence the critical concentration parameters for the SDS-HPMC aggregation and decreased to lower SDS concentrations with increasing ionic strength for both anionic and cationic surfactant-HPMC systems. From these data, other thermodynamic parameters of aggregation such as ΔHagg°, ΔGagg°, Hagg°, ΔSagg°, and ΔCp were calculated and utilized to postulate the hydrophobic nature of SDS-HPMC aggregate formation. The type of ionic surfactant head group (anionic vs. cationic i.e., dodecyltrimethylammonium bromide (DTAB)) was found to influence the strength of HPMC-surfactant interactions wherein a distinct CAC signifying the strength of HPMC-DTAB interactions was not observed. The interpretation of the microcalorimetric data at different temperatures and ionic strengths while varying properties of polymer and surfactant was a very effective tool in investigating the nature and energetics of HPMC and ionic surfactant interactions.
Collapse
Affiliation(s)
- Salin Gupta Patel
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, United States.
| | - Paul M Bummer
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, United States
| |
Collapse
|
8
|
Nanomilling of Drugs for Bioavailability Enhancement: A Holistic Formulation-Process Perspective. Pharmaceutics 2016; 8:pharmaceutics8020017. [PMID: 27213434 PMCID: PMC4932480 DOI: 10.3390/pharmaceutics8020017] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 05/13/2016] [Accepted: 05/13/2016] [Indexed: 11/17/2022] Open
Abstract
Preparation of drug nanoparticles via wet media milling (nanomilling) is a very versatile drug delivery platform and is suitable for oral, injectable, inhalable, and buccal applications. Wet media milling followed by various drying processes has become a well-established and proven formulation approach especially for bioavailability enhancement of poorly water-soluble drugs. It has several advantages such as organic solvent-free processing, tunable and relatively high drug loading, and applicability to a multitude of poorly water-soluble drugs. Although the physical stability of the wet-milled suspensions (nanosuspensions) has attracted a lot of attention, fundamental understanding of the process has been lacking until recently. The objective of this review paper is to present fundamental insights from available published literature while summarizing the recent advances and highlighting the gap areas that have not received adequate attention. First, stabilization by conventionally used polymers/surfactants and novel stabilizers is reviewed. Then, a fundamental understanding of the process parameters, with a focus on wet stirred media milling, is revealed based on microhydrodynamic models. This review is expected to bring a holistic formulation-process perspective to the nanomilling process and pave the way for robust process development scale-up. Finally, challenges are indicated with a view to shedding light on future opportunities.
Collapse
|
9
|
Bilgili E, Li M, Afolabi A. Is the combination of cellulosic polymers and anionic surfactants a good strategy for ensuring physical stability of BCS Class II drug nanosuspensions? Pharm Dev Technol 2015; 21:499-510. [DOI: 10.3109/10837450.2015.1022788] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
10
|
Szafraniec J, Janik M, Odrobińska J, Zapotoczny S. Nanocapsules templated on liquid cores stabilized by graft amphiphilic polyelectrolytes. NANOSCALE 2015; 7:5525-5536. [PMID: 25737427 DOI: 10.1039/c5nr00064e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A surfactant-free method of preparation of nanocapsules templated on liquid cores using amphiphilic graft polyelectrolytes was developed. A model photoactive copolymer, poly(sodium 2-acrylamido-2-methyl-1-propanesulfonate) with grafted poly(vinylnaphthalene) chains (PAMPS-graft-PVN) was used to stabilize toluene droplets in an aqueous emulsion. The macromolecules, due to their amphiphilic character and the presence of strong ionic groups, tend to undergo intramolecular aggregation in water but at the water-oil interface less compact conformation is preferred with PVN grafts anchoring in the oil phase and the charged PAMPS main chains residing in the aqueous phase, thus stabilizing the nanoemulsion droplets. Formation of such nanocapsules was confirmed by dynamic light scattering measurements as well as SEM and cryo-TEM imaging. Grafting density and content of the chromophores in the graft copolymers were varied in order to achieve high stability of the coated nanodroplets. It was shown that the capsules are better stabilized by the copolymers with many short hydrophobic grafts than with fewer but longer ones. Use of photoactive polyelectrolytes enabled spectroscopic investigation of the relationship between conformation of the macromolecules and stabilization of the oil-core nanocapsules. Long-term stability of the nanocapsules was achieved and further increased by multilayer shell formation using polyelectrolytes deposited via the layer-by-layer approach. The obtained capsules served as efficient nanocontainers for a hydrophobic fluorescent probe. The proposed strategy of nanocapsule preparation may be easily extended to biologically relevant polymers and applied to fabricate liquid core nanodelivery systems without the need of using low molecular weight additives which may have adverse effects in numerous biomedical applications.
Collapse
Affiliation(s)
- Joanna Szafraniec
- Jagiellonian University, Faculty of Chemistry, Ingardena 3, 30-060 Krakow, Poland.
| | | | | | | |
Collapse
|
11
|
Hong C, Dang Y, Lin G, Yao Y, Li G, Ji G, Shen H, Xie Y. Effects of stabilizing agents on the development of myricetin nanosuspension and its characterization: an in vitro and in vivo evaluation. Int J Pharm 2014; 477:251-60. [PMID: 25445518 DOI: 10.1016/j.ijpharm.2014.10.044] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 09/27/2014] [Accepted: 10/15/2014] [Indexed: 01/18/2023]
Abstract
Although myricetin has various pharmacological applications, it shows low oral bioavailability (<10%) in rats due to its poor aqueous solubility. To overcome this issue, myricetin nanosuspensions were developed and the effects of stabilizers were investigated. Based on the particle size and zeta potential, stabilizers soya lecithin, TPGS, HP-β-CD, and/or a combination thereof were used. The prepared nanosuspensions were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray powder diffraction (XRD). The resulting myricetin nanosuspensions contained particles in the size range of 300-500 nm and were physically stable. Myricetin was partially transformed from crystalline to amorphous forms in the presence of different excipients after the nanosizing process. The solubility and in vitro dissolution of all myricetin nanosuspensions were greatly increased compared with those of the myricetin powder. Consequently, the relative bioavailability in rats were 2.44, 3.57, 1.61, and 2.96 for nanosuspensions stabilized with TPGS, soya lecithin, soya lecithin+TPGS, and HP-β-CD+TPGS, respectively, relative to that of the coarse myricetin. This research demonstrated that nanosuspension is a promising strategy for delivering poor water-soluble drugs such as myricetin and that stabilizers played a critical role in the formulation design of myricetin nanosuspensions.
Collapse
Affiliation(s)
- Chao Hong
- Research Center for Health and Nutrition, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, China
| | - Yang Dang
- Research Center for Health and Nutrition, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, China
| | - Guobei Lin
- Research Center for Health and Nutrition, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, China
| | - Yashu Yao
- Research Center for Health and Nutrition, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, China; Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Guowen Li
- Pharmacy Department, Shanghai TCM-integrated Hospital, Shanghai 200082, China
| | - Guang Ji
- Institute of Digestive Diseases, Long Hua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200032, China
| | - Hongyi Shen
- Research Center for Health and Nutrition, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, China
| | - Yan Xie
- Research Center for Health and Nutrition, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, China.
| |
Collapse
|
12
|
Afolabi A, Akinlabi O, Bilgili E. Impact of process parameters on the breakage kinetics of poorly water-soluble drugs during wet stirred media milling: A microhydrodynamic view. Eur J Pharm Sci 2014; 51:75-86. [DOI: 10.1016/j.ejps.2013.09.002] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 08/02/2013] [Accepted: 09/02/2013] [Indexed: 11/25/2022]
|
13
|
Knieke C, Azad M, Davé R, Bilgili E. A study of the physical stability of wet media-milled fenofibrate suspensions using dynamic equilibrium curves. Chem Eng Res Des 2013. [DOI: 10.1016/j.cherd.2013.02.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
14
|
Ali MS, Rub MA, Khan F, Al-Lohedan HA. Thermodynamic, interfacial and hydrodynamic aspects of interaction of cationic drug amitriptyline hydrochloride with anionic and nonionic polymers. J Mol Liq 2013. [DOI: 10.1016/j.molliq.2013.01.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
15
|
Ali MS, Al-Lohedan HA. Interaction of biocompatible polymers with amphiphilic phenothiazine drug chlorpromazine hydrochloride. J Mol Liq 2013. [DOI: 10.1016/j.molliq.2012.10.037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
16
|
Bilgili E, Afolabi A. A combined microhydrodynamics–polymer adsorption analysis for elucidation of the roles of stabilizers in wet stirred media milling. Int J Pharm 2012; 439:193-206. [DOI: 10.1016/j.ijpharm.2012.09.040] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Revised: 08/20/2012] [Accepted: 09/17/2012] [Indexed: 11/30/2022]
|
17
|
Cerdeira AM, Werner IA, Mazzotti M, Gander B. Simultaneous quantification of polymeric and surface active stabilizers of nanosuspensions by using near-infrared spectroscopy. Drug Dev Ind Pharm 2012; 38:1360-70. [DOI: 10.3109/03639045.2011.650864] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
18
|
Li Y, Chen X, Zhang X, Zhu F, Zhu Y. Complexation behaviour of cellulose derivative/surfactant mixtures investigated by nonlinear enhanced Rayleigh scattering. Colloid Polym Sci 2011. [DOI: 10.1007/s00396-011-2390-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
19
|
Chen L, Chen DH, Wu CL. Studying flocculation mechanism of chitosan with pyrene-fluorescence probe method. CHINESE J CHEM 2010. [DOI: 10.1002/cjoc.20030210924] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
20
|
Lee MK, Kim S, Ahn CH, Lee J. Hydrophilic and hydrophobic amino acid copolymers for nano-comminution of poorly soluble drugs. Int J Pharm 2009; 384:173-80. [PMID: 19788919 DOI: 10.1016/j.ijpharm.2009.09.041] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2009] [Revised: 09/02/2009] [Accepted: 09/22/2009] [Indexed: 11/17/2022]
Abstract
Nano-comminution has successfully brought nanoparticle formulations of poorly soluble drugs to our daily life. The key for the successful nano-comminution of a drug is the choice of a proper polymeric steric stabilizer. To systematically elucidate the rationale of stabilizer selection, two types of helical amino acid copolymers, relatively hydrophilic and hydrophobic copolymers, were used in nano-comminution. The hydrophilic copolymers had lysine as their major component. The addition of relatively hydrophobic leucine and phenylalanine to them could not make significant changes in particle size. However, when a small amount of hydrophilic glutamic acid or lysine was added into elastin-like hydrophobic copolymers of valine, glycine, and proline, significant composition dependence was found. Therefore, specific interactions between the functional groups of polymers and drug surfaces seem to be important for successful nano-comminution. The stimuli responsive behavior of the hydrophobic copolymer induced the temperature dependence of particle size.
Collapse
Affiliation(s)
- M K Lee
- Department of Chemical Engineering and Materials Science, Chung-Ang University, 221 Heukseok-dong, Dongjak-gu, Seoul 156-756, South Korea
| | | | | | | |
Collapse
|
21
|
Choi JY, Park CH, Lee J. Effect of Polymer Molecular Weight on Nanocomminution of Poorly Soluble Drug. Drug Deliv 2008; 15:347-53. [DOI: 10.1080/10717540802039113] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
|
22
|
Thompson CJ, Ding C, Qu X, Yang Z, Uchegbu IF, Tetley L, Cheng WP. The effect of polymer architecture on the nano self-assemblies based on novel comb-shaped amphiphilic poly(allylamine). Colloid Polym Sci 2008. [DOI: 10.1007/s00396-008-1925-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
23
|
John Bosco S, Zettl H, Crassous JJ, Ballauff M, Krausch G. Interactions between Methyl Cellulose and Sodium Dodecyl Sulfate in Aqueous Solution Studied by Single Molecule Fluorescence Correlation Spectroscopy. Macromolecules 2006. [DOI: 10.1021/ma0616920] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S. John Bosco
- Physikalische Chemie II, Universität Bayreuth, 95440, Bayreuth, Germany, and Physikalische Chemie I, Universität Bayreuth, 95440, Bayreuth, Germany
| | - H. Zettl
- Physikalische Chemie II, Universität Bayreuth, 95440, Bayreuth, Germany, and Physikalische Chemie I, Universität Bayreuth, 95440, Bayreuth, Germany
| | - J. J. Crassous
- Physikalische Chemie II, Universität Bayreuth, 95440, Bayreuth, Germany, and Physikalische Chemie I, Universität Bayreuth, 95440, Bayreuth, Germany
| | - M. Ballauff
- Physikalische Chemie II, Universität Bayreuth, 95440, Bayreuth, Germany, and Physikalische Chemie I, Universität Bayreuth, 95440, Bayreuth, Germany
| | - G. Krausch
- Physikalische Chemie II, Universität Bayreuth, 95440, Bayreuth, Germany, and Physikalische Chemie I, Universität Bayreuth, 95440, Bayreuth, Germany
| |
Collapse
|
24
|
Lee J, Cheng Y. Critical freezing rate in freeze drying nanocrystal dispersions. J Control Release 2006; 111:185-92. [PMID: 16430987 DOI: 10.1016/j.jconrel.2005.12.003] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2005] [Revised: 11/09/2005] [Accepted: 12/12/2005] [Indexed: 10/25/2022]
Abstract
Recent advances in nanoparticle technologies have significantly enhanced the oral and parenteral delivery of poorly water-soluble active pharmaceutical ingredients (APIs). However, reports have been limited on the various drying procedures to convert a liquid nanocrystal dispersions into solid dosage forms. The solid dosage form should consist of nanocrystals that can readily reconstitute into their original size upon dissolution in water. Herein, the freeze drying process of nanocrystal dispersions was examined at varying freezing rates (speed of freezing interface). As freezing rate decreases, more particle-particle aggregation developed. A critical freezing rate, below which the dried nanocrystals cannot be re-dispersed, was identified based on the plot of the particle size of reconstituted nanocrystals versus freezing rate. Freeze drying at a freezing rate near the critical value produces dry powders of bimodal particle size distribution after re-dispersion. In addition, API concentration was found to significantly affect the critical freezing rate and therefore the re-dispersibility of dry powders. The concept of critical freezing rate is critical for the development of solid dosage forms of liquid nanocrystal dispersions.
Collapse
Affiliation(s)
- Jonghwi Lee
- Department of Chemical Engineering and Materials Science, Chung-Ang University, 221 Heukseok-dong, Dongjak-gu, Seoul 156-756, Korea (South).
| | | |
Collapse
|
25
|
Wittgren B, Stefansson M, Porsch B. Interactions between sodium dodecyl sulphate and non-ionic cellulose derivatives studied by size exclusion chromatography with online multi-angle light scattering and refractometric detection. J Chromatogr A 2005; 1082:166-75. [PMID: 16035358 DOI: 10.1016/j.chroma.2005.05.047] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The novel approach described allows to characterise the surfactant-polymer interaction under several sodium dodecyl sulphate (SDS) concentrations (0-20 mM) using size exclusion chromatography (SEC) with online multi-angle light scattering (MALS) and refractometric (RI) detection. Three different cellulose derivatives, hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC) and hydroxyethyl cellulose (HEC), have been studied in solution containing 10 mM NaCl and various concentrations of sodium dodecyl sulphate. It is shown that this approach is well suited for successful application of both Hummel-Dreyer and multi-component light scattering principles and yields reliable molecular masses of both the polymer complex and the polymer itself within the complex, the amount of surfactant bound into the complex as well as appropriate values of the refractive index increment (dn/dc)micro, of both the complex and the polymer in question. The more hydrophobic derivatives HPC and HPMC adsorbed significantly more SDS than HEC. The inter-chain interactions close to critical aggregation concentration (cac) were clearly seen for HPC and HPMC as an almost two-fold average increase in polymer molecular mass contained in the complex.
Collapse
|
26
|
Lee J, Lee SJ, Choi JY, Yoo JY, Ahn CH. Amphiphilic amino acid copolymers as stabilizers for the preparation of nanocrystal dispersion. Eur J Pharm Sci 2005; 24:441-9. [PMID: 15784334 DOI: 10.1016/j.ejps.2004.12.010] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2004] [Revised: 12/22/2004] [Accepted: 12/27/2004] [Indexed: 10/25/2022]
Abstract
The recent advance of particle size engineering in nanometer ranges has widened the formulation opportunities of relatively water-insoluble drugs. However, the 'nanoformulation' suffers from a lack of systematic understanding about the requirements of polymeric stabilizers. Furthermore, the polymers that can be used for the preparation of nanocrystals are so limited that finding a proper stabilizer for a given formulation is often difficult. In this study, amino acid copolymers whose properties can systematically be tailored are developed, and their morphological and compositional effects are investigated. Copolymers containing lysine (K) as their hydrophilic segments, and phenylalanine (F) or leucine (L) as their hydrophobic segments successfully produce stable nanocrystals (200-300 nm) in water, while copolymers of K and alanine (A) could not generate nanosized particles. Not the morphology but the hydrophobicity of copolymers seems to be a critical parameter in the preparation of drug nanocrystals by wet comminution. The effective stabilization performance of copolymers requires the hydrophobic moiety content to be higher than 15 mol%. Comminution for only 5 min is long enough for nanocrystal preparation, and the crystallinity of drug is found intact after the processing.
Collapse
Affiliation(s)
- Jonghwi Lee
- Department of Nano Science and Engineering, Biomaterials Research Group, Sejong University, Kwang-Jin-Gu, Gun-Ja-Dong 98, Seoul, South Korea
| | | | | | | | | |
Collapse
|
27
|
Silvério CA, Okano LT. Laser flash photolysis and time-resolved fluorescence measurements of the aggregation number of SDS–biopolymer complexes. Colloids Surf B Biointerfaces 2004; 38:41-6. [PMID: 15465303 DOI: 10.1016/j.colsurfb.2004.08.015] [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: 07/09/2004] [Revised: 08/19/2004] [Accepted: 08/20/2004] [Indexed: 10/26/2022]
Abstract
Aqueous solutions of 0.5% sodium carboxymethyl cellulose, NaCMC, and 2-hydroxyethyl cellulose, HEC, and variable concentration of sodium dodecyl sulfate, SDS, were studied by the intensities ratio of pyrene fluorescence bands (I/III and monomer/excimer) and conductance measurements to determine the critical aggregation concentration, cac, and the degree of micellar dissociation, alpha, respectively. The cac of these systems is close to 2-4 x 10(-3)M and values of alpha are consistent with the formation of SDS micelles adsorbed cooperatively to the polymer backbone. Laser flash photolysis (LFP) and time-resolved fluorescence (TRF) techniques were employed to determine the micellar aggregation number, N, using the probes flavone and pyrene, respectively. The obtained N for HEC/SDS and NaCMC/SDS were 48 and 68, respectively. The presence of the counterions at the NaCMC backbone is the main factor responsible for this number. Besides, the transient spectra of flavone and present in 0.5% HEC or NaCMC with and in absence of SDS are discussed. Flavone triplet state exit rate constant from the biopolymer/SDS complexes showed that these systems are completely different from a pure SDS micelle.
Collapse
Affiliation(s)
- Cristina A Silvério
- Departamento de Química da Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto-USP, Av. dos Bandeirantes, 3900 Ribeirão Preto, SP 14040-901, Brazil
| | | |
Collapse
|
28
|
Ridell A, Evertsson H, Nilsson S. Influence of Counterion on the Interaction of Dodecyl Sulfates and Cellulose Ethers. J Colloid Interface Sci 2002; 247:381-8. [PMID: 16290478 DOI: 10.1006/jcis.2001.8151] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2000] [Accepted: 12/10/2001] [Indexed: 11/22/2022]
Abstract
Fluorescence probe techniques together with microcalorimetry and dye solubilization were used to study the interaction between nonionic polymers and anionic surfactants with different monovalent counterions in order to examine the effects of the counterion. The polymers used were the cellulose ethers hydroxypropyl methyl cellulose (HPMC) and ethyl hydroxyethyl cellulose (EHEC). The surfactants were dodecyl sulfates with potassium, sodium, and lithium as counterions (KDS, NaDS, LiDS). The counterion influenced the interaction start concentration as well as the nature of the mixed aggregates formed. The interaction start, according to surfactant concentration, was found to be in the order KDS < NaDS < LiDS for both polymers as well as in aqueous solution. From fluorescence measurements it was found that the KDS-polymer aggregates shield pyrene from water better than the other surfactants, indicating larger aggregates with a more fluid interior. The microcalorimetry measurements confirm that the adsorption of the surfactants onto the polymer is endothermic and entropy driven at the start and as more clusters are formed on the polymer chains the process converts to being exothermic and driven by both enthalpy and entropy.
Collapse
Affiliation(s)
- Annika Ridell
- Physical Pharmaceutical Chemistry, Uppsala Biomedical Centre, Uppsala University, Box 580, Uppsala, S-751 23, Sweden.
| | | | | |
Collapse
|
29
|
Interactions of a hydrophobically modified cationic cellulose ether derivative with amphiphiles of like charge in an aqueous environment. Carbohydr Polym 2001. [DOI: 10.1016/s0144-8617(00)00254-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
30
|
Ruiz CC. Fluorescence Anisotropy of Probes Solubilized in Micelles of Tetradecyltrymethylammonium Bromide: Effect of Ethylene Glycol Added. J Colloid Interface Sci 2000; 221:262-267. [PMID: 10631029 DOI: 10.1006/jcis.1999.6555] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This paper deals with the effect of ethylene glycol on the micelle formation of tetradecyltrimethylammonium bromide. The effect of ethylene glycol addition on the fluorescence anisotropy of several probe molecules residing in different regions of the micelle was investigated to address the solvent penetration in the micelle structure. Fluorescence depolarization measurements were carried out on micellar systems containing two different hydrophobic dyes, namely, perylene and diphenylbutadiene, and a hydrophilic one, fluorescein. The steady-state anisotropy values obtained in these experiments were used to estimate the microviscosity of the corresponding micellar regions. It is observed that the microviscosity in the hydrophobic regions of micelles were roughly constant with EG addition, indicating that the micellar interior does not undergo significant structural changes by the presence of cosolvent in the solution. However, the microviscosity at the micellar surface, as determined by using fluorescein as a probe, is found to increase with EG addition. This perturbation of the micellar surface is ascribed to the solvent penetration in this region of the micelle, where there is probably participation in the solvation layer of the micelle headgroups. Copyright 2000 Academic Press.
Collapse
Affiliation(s)
- CC Ruiz
- Departamento de Física Aplicada II, Escuela Universitaria Politécnica, Universidad de Málaga, Campus de El Ejido, Málaga, 29013, Spain
| |
Collapse
|
31
|
Microstructures formed in aqueous solutions of a hydrophobically modified nonionic cellulose derivative and sodium dodecyl sulfate: a fluorescence probe investigation. Carbohydr Polym 1999. [DOI: 10.1016/s0144-8617(99)00065-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
32
|
Ridell A, Evertsson H, Nilsson S, Sundelöf LO. Amphiphilic association of ibuprofen and two nonionic cellulose derivatives in aqueous solution. J Pharm Sci 1999; 88:1175-81. [PMID: 10564067 DOI: 10.1021/js990092u] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The aqueous interaction of the sodium salt of ibuprofen with the cellulose ethers ethyl hydroxyethyl cellulose, EHEC, and hydroxypropyl methyl cellulose, HPMC, has been investigated in the concentration range 0-500 mM ibuprofen and 0.1-1% (w/w) polymer, by cloud point, capillary viscometry, equilibrium dialysis, and fluorescence probe techniques. Ibuprofen forms micelles in pure water, with the critical micelle concentration, cmc, at 180 mM. A combination of time-resolved and static fluorescence quenching shows that micelle-like ibuprofen aggregates are formed in the solution. The average aggregation number of pure ibuprofen micelles in water is about 40. In the presence of EHEC or HPMC the aggregation numbers decrease. The interaction of ibuprofen with cellulose ethers is similar to the normally accepted model for polymer-surfactant interaction, although more complex. Ibuprofen adsorbs to the polymer in the form of mixed polymer-drug micelles, noncooperatively up to cmc and cooperatively when cmc is passed. The interaction starts below 50 mM ibuprofen as monitored by the fluorescent probes pyrene and 1,3-di(1-pyrenyl)propane, P3P, with a maximum in microviscosity below cmc, corresponding to polymer-dense mixed micelles. The study illustrates the importance of a precise apprehension of the aggregation behavior as a background for transport studies in drug-polymer systems.
Collapse
Affiliation(s)
- A Ridell
- Physical Pharmaceutical Chemistry, Uppsala University, Uppsala Biomedical Centre, Box 574, S-751 23, Uppsala, Sweden
| | | | | | | |
Collapse
|
33
|
Persson B, Nilsson S, Bergman R. Dynamic Surface Tension of Dilute Aqueous Solutions of Nonionic Cellulose Derivatives in Relation to Other Macromolecular Characterization Parameters. J Colloid Interface Sci 1999; 218:433-441. [PMID: 10502375 DOI: 10.1006/jcis.1999.6449] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The dynamic surface tension of 10 nonionic water soluble cellulose derivatives with molecular weights (M(w)) in the range 100,000-1,300,000 has been measured by the pendant drop method at the water/air interface. The surface tension measured after 11.7 h, gamma*, was taken as an apparent steady state surface tension. The gamma* at the highest concentration, 500 ppm, gamma*(500), showed values from 63 to 37 mN/m, and the value of gamma*(500) depends on the hydrophilic/hydrophobic balance of the polymer. The aim of the present work was to discuss the dynamic surface tension in relation to some other characterization parameters, like M(w), diffusion coefficient, intrinsic viscosity ([eta]), cloud point, and degree of hydrophilic/hydrophobic substitution. Dynamic surface tension was shown in a concentration range of 2-10 ppm. The time to reach (gamma(H2O)-gamma*)/2, defined as t(1/2), was found to be inversely correlated both to the diffusion coefficient and to the square of the bulk concentration, which can be expected for a diffusion controlled process. The time t(1/2) showed an approximately linear relationship against [eta](1/3). The pendant drop was found to decrease in volume with time due to the high vapor pressure caused by the curvature of the drop (DeltaP = 2gamma/r(drop)). Copyright 1999 Academic Press.
Collapse
Affiliation(s)
- B Persson
- Physical Pharmaceutical Chemistry, Uppsala University, Uppsala, S-751 23, Sweden
| | | | | |
Collapse
|
34
|
Hugerth A, Nilsson S, Sundelöf LO. Gel--sol transition in kappa-carrageenan systems: microviscosity of hydrophobic microdomains, dynamic rheology and molecular conformation. Int J Biol Macromol 1999; 26:69-76. [PMID: 10520958 DOI: 10.1016/s0141-8130(99)00065-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The effect of gel-sol transition in kappa-carrageenan systems on the microviscosity of hydrophobic microdomains, as well as its relation to macroscopic rheology and molecular conformation, was studied in kappa-carrageenan systems. The microdomains were probed by 1,3-di(-1-pyrenyl)propane (P3P) for which the excimer intensity (Ie) provides relative measures of the microviscosity in the immediate probe surroundings. In particular the applicability of P3P to monitor the gel--sol transition was proved, the results showing a dramatic decrease in microviscosity in the vicinity of the transition point. The corresponding changes in rheological properties and carrageenan conformation were investigated by dynamic viscometry (DV) and optical rotation (OR), respectively. The temperature of onset of the transition as indicated by the microviscosity data (T0) was found to correlate well with the OR and DV-results. The application of microviscosity and OR-measurements allowed an estimation of the helical content at T0 to be determined. P3P-data indicate a microenvironment viscosity for the probe sites in the kappa-carrageenan system comparable to that found in SDS micelles.
Collapse
Affiliation(s)
- A Hugerth
- Physical Pharmaceutical Chemistry, Faculty of Pharmacy, Uppsala University, Uppsala Biomedical Center, Sweden
| | | | | |
Collapse
|
35
|
Persson B, Evertsson H, Bergman R, Sundelöf LO. Multivariate parameter evaluation of pharmaceutically important cellulose ethers. J Pharm Sci 1999; 88:767-74. [PMID: 10430540 DOI: 10.1021/js9804922] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A set of nonionic cellulose ethers with varying hydrophobicity and molecular weight has been investigated by principal component analysis (PCA). Several experimental variables such as dynamic surface tension, diffusion coefficient, microviscosity as monitored by a fluorescence probe technique, and intrinsic viscosity are included in the analysis. The experimental variables and observations (polymer fractions) are analyzed in models with good predictive capacities. The apparent equilibrium surface tension correlates to the cloud point and to the critical aggregation concentration in the presence of surfactant. The microviscosity is shown to be a predictive parameter for the degree of hydrophobic substitution. The irreversible process of dynamic surface tension is dependent on the diffusion coefficient but to an even larger degree on the polymer concentration, which is well illustrated by the PCA models.
Collapse
Affiliation(s)
- B Persson
- Physical Pharmaceutical Chemistry, Uppsala University, Uppsala Biomedical Centre, Box 574, 751 23 Uppsala, Sweden, and SPOC, UF3A1, Pharmacia & Upjohn, 751 82 Uppsala
| | | | | | | |
Collapse
|
36
|
Zana R. Microviscosity of Aqueous Surfactant Micelles: Effect of Various Parameters. J Phys Chem B 1999. [DOI: 10.1021/jp990347s] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- R. Zana
- Institut C. Sadron, CNRSULP, 6 rue Boussingault, 67000 Strasbourg, France
| |
Collapse
|
37
|
Singh SK, Nilsson S. Thermodynamics of Interaction between Some Cellulose Ethers and SDS by Titration Microcalorimetry. J Colloid Interface Sci 1999; 213:133-151. [PMID: 10191016 DOI: 10.1006/jcis.1999.6122] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The interaction between certain nonionic cellulose ethers (ethyl hydroxyethyl cellulose and hydroxypropyl methyl cellulose) and sodium dodecyl sulphate (SDS) has been investigated using isothermal titration microcalorimetry at temperatures between 25-50 degrees C. The observed heat flow curves have been interpreted in terms of a plausible mechanism of the interaction of the substituent groups with SDS monomers and clusters. The data have been related to changes occuring in the system at the macro- and microscopic levels with the addition of surfactants and with temperature. The process consists predominantly of polymer-surfactant interactions initially and surfactant-surfactant interactions at the later stages. A phenomenological model of the cooperative interaction (adsorption) process has been derived, and earlier published equilibrium binding data have been used to recover binding constants and Gibbs energy changes for this process. The adsorption enthalpies and entropies have been recovered along with the heat capacity change. The enthalpic cost of confining the nonpolar regions of the polymers in surfactant clusters is high, but the entropy gain from release of hydration shell water molecules as well as increased freedom of movement of these nonpolar regions in the clusters gives the process a strong entropic driving force. The process is entropy-driven initially and converts to being both enthalpy and entropy-driven at high SDS concentrations. An enthalpy-entropy compensation behavior is seen. Strongly negative heat capacity changes have been obtained resulting from the transfer of nonpolar groups from aqueous into nonpolar environments, as well as a reduction of conformational domains that the chains can populate. Changes in these two components cause the heat capacity change to become less negative at the higher binding levels. The system can be classified as exhibiting nonclassical hydrophobic binding at the later stages of binding. Copyright 1999 Academic Press.
Collapse
Affiliation(s)
- SK Singh
- Department of Pharmaceutics, Pharmacia & Upjohn AB, Uppsala, S-751 82, Sweden
| | | |
Collapse
|
38
|
Microviscosity in dilute aqueous solutions of SDS and non-ionic cellulose derivatives of different hydrophobicity: fluorescence probe investigations. Carbohydr Polym 1998. [DOI: 10.1016/s0144-8617(97)00239-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
39
|
Holmberg C, Evertsson H. Salt influence in the polymer-surfactant interaction in solution. A fluorescence probe investigation of the EHEC/SDS/ water system. Colloid Polym Sci 1997. [DOI: 10.1007/s003960050155] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|