1
|
Yang AC, Weng CI, Chen TC. Behavior of water molecules near monolayer-protected clusters with different terminal segments of ligand. J Chem Phys 2011; 135:034101. [DOI: 10.1063/1.3602721] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
2
|
Padula C, Nicoli S, Colombo P, Santi P. Single-layer transdermal film containing lidocaine: Modulation of drug release. Eur J Pharm Biopharm 2007; 66:422-8. [PMID: 17196804 DOI: 10.1016/j.ejpb.2006.11.014] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2006] [Revised: 11/14/2006] [Accepted: 11/21/2006] [Indexed: 10/23/2022]
Abstract
We have recently described an innovative drug delivery system, a water-based and vapor permeable film intended for dermal and/or transdermal delivery. The aim of this work was to modulate the delivery of the model drug lidocaine hydrochloride from the transdermal film across rabbit ear skin. The effect of drug loading, of film-forming polymer type and content, of adhesive and plasticizer on lidocaine transport across the skin was evaluated. Additional objective was to evaluate the effect of occlusion on the kinetics of lidocaine transport, by applying an occlusive backing on the surface of the transdermal film. From the data obtained it can be concluded that the transdermal film acts as a matrix controlling drug delivery. The film-forming polymer molecular weight had a negligible effect on drug penetration, while its content was more effective. The choice of the adhesive seems to be the most important variable governing drug transport. In particular, the presence of lauric acid combined with a basic drug, such as lidocaine, can produce a relevant improvement in permeation, because of the formation of an ion pair. Concerning the kinetics, drug depletion is responsible for the declining permeation rates observed in the late times of permeation.
Collapse
|
3
|
Artusi M, Nicoli S, Colombo P, Bettini R, Sacchi A, Santi P. Effect of chemical enhancers and iontophoresis on thiocolchicoside permeation across rabbit and human skin in vitro. J Pharm Sci 2004; 93:2431-8. [PMID: 15349953 DOI: 10.1002/jps.20152] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The aim of this work was to study the permeation of thiocolchicoside across the skin in vitro. The effect of the chemical enhancer lauric acid and the physical technique of iontophoresis was investigated. Permeation experiments were performed in vitro using rabbit ear skin as barrier. The effect of lauric acid at different concentrations (2% and 4%) and of the vehicle (water, ethanol, or ethanol/water) was investigated. The primary effect of lauric acid was on the partitioning parameter, whereas the diffusive parameter did not change significantly. When human epidermis was used, the permeation parameters were generally lower, although not significantly different from rabbit ear skin. The data obtained with full-thickness human skin indicate that, despite the hydrophilic nature of thiocolchicoside, the resistance to drug transport is not limited to the stratum corneum, but that the underlying dermal tissue can also contribute. Iontophoresis enhanced the flux of thiocolchicoside compared with the passive control. The mechanism by which iontophoresis enhanced thiocolchicoside transport across the skin was electroosmosis. The permeation of thiocolchicoside across the skin can be enhanced using chemical or physical penetration enhancers.
Collapse
Affiliation(s)
- Mariella Artusi
- Dipartimento Farmaceutico, University of Parma, Parco Area delle Scienze 27/A, 43100 Parma, Italy
| | | | | | | | | | | |
Collapse
|
4
|
Baynes RE, Riviere JE. Mixture additives inhibit the dermal permeation of the fatty acid, ricinoleic acid. Toxicol Lett 2004; 147:15-26. [PMID: 14700524 DOI: 10.1016/j.toxlet.2003.09.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Ricinoleic acid (RA) like many of the ingredients in machine cutting fluids and other industrial formulations are potential dermal irritants, yet very little is known about its permeability in skin. 3H-ricinoleic acid mixtures were formulated with three commonly used cutting fluid additives; namely, triazine (TRI), linear alkylbenzene sulfonate (LAS), and triethanolamine (TEA) and topically applied to inert silastic membranes and porcine skin in vitro as aqueous mineral oil (MO) or polyethylene glycol (PEG) mixtures. These additives significantly decreased ricinoleic acid partitioning from the formulation into the stratum corneum (SC) in PEG-based mixtures. Except for LAS, all other additives produced a more basic formulation (pH = 9.3-10.3). In silastic membranes and porcine skin, individual additives or combination of additives significantly reduced ricinoleic permeability. This trend in ricinoleic acid disposition in both membranes suggests that the mixture interaction is more physicochemical in nature and probably not related to the chemical-induced changes in the biological membrane as may be assumed with topical exposures to potentially irritant formulations.
Collapse
Affiliation(s)
- R E Baynes
- Center for Chemical Toxicology Research and Pharmacokinetics, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA.
| | | |
Collapse
|
5
|
Li GL, van der Geest R, Chanet L, van Zanten E, Danhof M, Bouwstra JA. In vitro iontophoresis of R-apomorphine across human stratum corneum. Structure-transport relationship of penetration enhancement. J Control Release 2002; 84:49-57. [PMID: 12399167 DOI: 10.1016/s0168-3659(02)00259-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To achieve a therapeutical effect of the anti-Parkinson's drug R-apomorphine via iontophoresis delivery, enhancement strategies in vitro were explored using three structurally related enhancers, lauric acid (LA), dodecyltrimethylammonium bromide (DTAB) and Laureth-3 oxyethylene ether (C(12)EO(3)). Human stratum corneum and shed snake skin were pretreated with 0.15 M each enhancer solution in propylene glycol (PG). Thereafter, passive diffusion, iontophoretic transport and post-iontophoretic passive diffusion were investigated. Compared to the control (PG pretreatment), a slight inhibition on both passive and iontophoretic delivery was observed with cationic surfactant DTAB pretreated stratum corneum. Pretreatment with anionic surfactant LA resulted in a great enhancement on passive delivery, but only a small enhancing effect on the iontophoretic delivery. Unlike the others, the nonionic surfactant C(12)EO(3) substantially increased iontophoretic transport rate of R-apomorphine by 2.3-fold, whereas passive delivery was basically unchanged or slightly affected. The magnitude of enhancing effect of C(12)EO(3) was dependent on the surfactant concentration and the pretreatment duration. Moreover, comparison of transport data through shed snake skin with human stratum corneum indicates that both shunt- and intercellular pathways are involved in the iontophoretic transport of R-apomorphine.
Collapse
Affiliation(s)
- Gai Ling Li
- Division of Pharmaceutical Technology, Leiden/Amsterdam Center for Drug Research, Leiden University, P.O. Box 9502, The Netherlands
| | | | | | | | | | | |
Collapse
|
6
|
Nicoli S, Rimondi S, Colombo P, Santi P. Physical and chemical enhancement of transdermal delivery of triptorelin. Pharm Res 2001; 18:1634-7. [PMID: 11758775 DOI: 10.1023/a:1013003103169] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- S Nicoli
- Department of Pharmacy, University of Parma, Italy
| | | | | | | |
Collapse
|
7
|
Sparr E, Wennerström H. Responding phospholipid membranes--interplay between hydration and permeability. Biophys J 2001; 81:1014-28. [PMID: 11463643 PMCID: PMC1301571 DOI: 10.1016/s0006-3495(01)75759-1] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Osmotic forces are important in regulating a number of physiological membrane processes. The effect of osmotic pressure on lipid phase behavior is of utmost importance for the extracellular lipids in stratum corneum (the outer part of human skin), due to the large gradient in water chemical potential between the water-rich tissue on the inside, and the relative dry environment on the outside of the body. We present a theoretical model for molecular diffusional transport over an oriented stack of two-component lipid bilayers in the presence of a gradient in osmotic pressure. This gradient serves as the driving force for diffusional motion of water. It also causes a gradient in swelling and phase transformations, which profoundly affect the molecular environment and thus the local diffusion properties. This feedback mechanism generates a nonlinear transport behavior, which we illustrate by calculations of the flux of water and solute (nicotine) through the bilayer stack. The calculated water flux shows qualitative agreement with experimental findings for water flux through stratum corneum. We also present a physical basis for the occlusion effect. Phase behavior of binary phospholipid mixtures at varying osmotic pressures is modeled from the known interlamellar forces and the regular solution theory. A first-order phase transformation from a gel to a liquid--crystalline phase can be induced by an increase in the osmotic pressure. In the bilayer stack, a transition can be induced along the gradient. The boundary conditions in water chemical potential can thus act as a switch for the membrane permeability.
Collapse
Affiliation(s)
- E Sparr
- Division of Physical Chemistry 1, Center for Chemistry and Chemical Engineering, Lund University, SE-22100 Lund, Sweden.
| | | |
Collapse
|
8
|
Pagliara A, Reist M, Geinoz S, Carrupt PA, Testa B. Evaluation and prediction of drug permeation. J Pharm Pharmacol 1999; 51:1339-57. [PMID: 10678488 DOI: 10.1211/0022357991777164] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
A major challenge confronting the pharmaceutical scientist is to optimize the selective and efficient delivery of new active entities and drug candidates. Successful drug development requires not only optimization of specific and potent pharmacodynamic activity, but also efficient delivery to the target site. Following advances in rational drug design, combinatorial chemistry and high-throughput screening techniques, the number of newly discovered and promising active compounds has increased dramatically in recent years, often making delivery problems the rate-limiting step in drug research. To overcome these problems, a good knowledge of the pharmacokinetic barriers encountered by bioactive compounds is required. This review gives an overview of the properties of relevant physiological barriers and presents some important biological models for evaluation of drug permeation and transport. Physicochemical determinants in drug permeation and the relevance of quantitative and qualitative approaches to the prediction and evaluation of passive drug absorption are also discussed.
Collapse
Affiliation(s)
- A Pagliara
- Institut de Chimie Thérapeutique, Université de Lausanne, Switzerland
| | | | | | | | | |
Collapse
|
9
|
Levang AK, Zhao K, Singh J. Effect of ethanol/propylene glycol on the in vitro percutaneous absorption of aspirin, biophysical changes and macroscopic barrier properties of the skin. Int J Pharm 1999; 181:255-63. [PMID: 10370221 DOI: 10.1016/s0378-5173(99)00055-1] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effect of the solvent systems ethanol (EtOH), propylene glycol (PG) and combinations thereof was examined on the in vitro percutaneous absorption of the antithrombotic, aspirin, through porcine epidermis. Biophysical changes in the stratum corneum lipids were studied through the use of Fourier transform infrared (FTIR) spectroscopy. Macroscopic barrier properties of the epidermis were examined through the use of in vitro transepidermal water loss (TEWL). The flux of aspirin increased with increasing concentrations of EtOH in the solvent systems. The maximum flux of aspirin was achieved by 80% EtOH in combination with 20% PG beyond which (i.e. 100% EtOH) there was no increase in the flux. FTIR spectroscopic study was enacted in order to determine the biophysical properties of the stratum corneum when the solvents were applied. The FTIR spectra of the stratum corneum treated with 80% EtOH/20% PG showed a maximum decrease in absorbance for the asymmetric and symmetric C&z. sbnd;H peaks, which suggests a greater loss of the lipids in the stratum corneum layers. In vitro TEWL studies allowed an investigation into the macroscopic barrier integrity properties of the stratum corneum. The TEWL results indicated that each of the solvent systems significantly enhanced (P<0.05) in vitro TEWL in comparison to the control. In conclusion, 80% EtOH/20% PG enhanced the percutaneous absorption of aspirin by perturbing the macroscopic barrier integrity of the stratum corneum and through a loss of stratum corneum lipids.
Collapse
Affiliation(s)
- A K Levang
- Department of Pharmaceutical Sciences, College of Pharmacy, North Dakota State University, Fargo, ND 58105, USA
| | | | | |
Collapse
|
10
|
Reymond F, Chopineaux-Courtois V, Steyaert G, Bouchard G, Carrupt PA, Testa B, Girault HH. Ionic partition diagrams of ionisable drugs: pH-lipophilicity profiles, transfer mechanisms and charge effects on solvation. J Electroanal Chem (Lausanne) 1999. [DOI: 10.1016/s0022-0728(98)00418-5] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
11
|
Effect of oleic acid/ethanol and oleic acid/propylene glycol on the in vitro percutaneous absorption of 5-fluorouracil and tamoxifen and the macroscopic barrier property of porcine epidermis. Int J Pharm 1998. [DOI: 10.1016/s0378-5173(97)00430-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
12
|
Xiang TX, Anderson BD. Phase structures of binary lipid bilayers as revealed by permeability of small molecules. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1370:64-76. [PMID: 9518554 DOI: 10.1016/s0005-2736(97)00244-7] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The effects of changes in bilayer phase structure on the permeability of acetic acid and trimethylacetic acid were studied in large unilamellar vesicles (LUVs) composed of dipalmitoylphosphatidylcholine (DPPC)/cholesterol (CHOL), dihexadecylphosphatidylcholine (DHPC)/CHOL, or DPPC/dimyristoylphosphatidylcholine (DMPC) using an NMR line-broadening method. Phase transitions were induced by changes in temperature and lipid composition (i.e., XCHOL was varied from 0.0 to 0.5 and XDMPC from 0.0 to 1.0). In DPPC/CHOL and DHPC/CHOL bilayers, the addition of CHOL induces only a modest change in the permeability coefficient (Pm) of acetic acid in the gel-phase (Pbeta') but significantly reduces Pm in ordered and disordered liquid-crystalline phases (Lo and Lalpha). Abrupt changes in slopes in semi-logarithmic plots of Pm vs. XCHOL occur at specific values of XCHOL and temperature corresponding to the boundaries between Pbeta' and Lo or between Lalpha and Lo phases. In most respects, phase diagrams generated from the break points in plots of Pm vs. XCHOL obtained at various temperatures in DHPC/CHOL and DPPC/CHOL bilayers closely resemble those constructed previously for DPPC/CHOL bilayers using NMR and DSC methods. Above Tm, the phase diagrams generated from permeability data reveal the presence of both the disordered (Lalpha) and the ordered (Lo) liquid-crystalline phases, as well as the two-phase coexistence region. In DPPC/DMPC bilayers, the addition of DMPC increases Pm dramatically in the gel phase but only slightly in the liquid-crystalline phase. Abrupt changes in slopes in semi-logarithmic plots of Pm vs. XDMPC also occur at specific values of XDMPC and temperature, from which a phase diagram can be constructed which closely resembles diagrams obtained previously by other methods. These correlations indicate that trans-bilayer permeability measurements can be used to construct lipid bilayer phase diagrams. Positive deviations of Pm from predicted values based on the phase lever rule are observed in the two-phase coexistence regions with the degree of the deviation depending on bilayer chemical composition and temperature. These results may reflect a specific contribution of the interfacial region between two phases to higher solute permeability or may be due to the higher lateral compressibility of lipid bilayers in the two-phase coexistence region.
Collapse
Affiliation(s)
- T X Xiang
- Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT 84108, USA
| | | |
Collapse
|