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Salimi A, Mohammad Soleymani H, Mohammad Soleymani S. Altered Skin Permeation of Finasteride Using Clove Oil, Urea, and Lyophilized Powder of Grape Seed Extract. Adv Pharm Bull 2023; 13:96-103. [PMID: 36721808 PMCID: PMC9871283 DOI: 10.34172/apb.2023.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 10/04/2021] [Accepted: 12/31/2021] [Indexed: 02/03/2023] Open
Abstract
Purpose: Finasteride is a 5-alpha reductase inhibitor used to treat hair loss and acne. The skin permeation of finasteride is one of the main challenges associated with dermal drug delivery. One way to overcome the skin barrier is to use penetration enhancers. The purpose of this study was to investigate the effect of some penetration enhancers on finasteride permeability on the skin, as well as the effect of pretreatment time on their efficacy. Methods: In order to determine the effect of penetration enhancers on the skin permeability of finasteride, the skin was exposed to clove oil, urea, and lyophilized powder of grape seed extract (LPGSE) at different pretreatment times (2, 4 h), and then the permeability parameters were determined by passing the drug through the skin. Results: The results of this study showed that clove oil, urea, and LPGSE increased the transfer of finasteride from the skin. The highest rate of permeation was observed with clove oil (4 h), and the least permeability was observed with urea (4 h). Conclusion: Increasing the pretreatment time with clove oil and LPGSE increases the permeability of finasteride. Meanwhile, the increase in pretreatment time with urea reduces the penetration of finasteride from the skin due to reversible effects.
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Affiliation(s)
- Anayatollah Salimi
- Nanotechnology Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran.,Department of Pharmaceutics, School of Pharmacy, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran
| | - Hamid Mohammad Soleymani
- Petroleum Research Laboratory, School of Chemical Engineering, Iran University of Science and Technology, Tehran, Iran
| | - Saeed Mohammad Soleymani
- Department of Clinical Pharmacy, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Corresponding Author: Saeed Mohammad Soleymani,
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2
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Goh CF, Hadgraft J, Lane ME. Thermal analysis of mammalian stratum corneum using differential scanning calorimetry for advancing skin research and drug delivery. Int J Pharm 2022; 614:121447. [PMID: 34998922 DOI: 10.1016/j.ijpharm.2021.121447] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 12/30/2021] [Accepted: 12/31/2021] [Indexed: 11/15/2022]
Abstract
For effective topical and transdermal drug delivery, it is necessary for most actives to penetrate and permeate through the stratum corneum (SC). Extensive investigation of the thermal behaviour of mammalian SC has been performed to understand the barrier function of the skin. However, little attention has been paid to the related experimental variables in thermal analysis of the SC using differential scanning calorimetry that may influence the results obtained from such studies. In this review, we provide a comprehensive overview of the thermal transitions of the SC of both porcine and human skin. More importantly, the selection and impact of the experimental and instrumental parameters used in thermal analysis of the SC are critically evaluated. New opportunities for the use of thermal analysis of mammalian SC in advancing skin research, particularly for elucidation of the actions of excipients employed in topical and transdermal formulations on the skin are also highlighted.
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Affiliation(s)
- Choon Fu Goh
- Discipline of Pharmaceutical Technology, School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.
| | - Jonathan Hadgraft
- Department of Pharmaceutics, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom
| | - Majella E Lane
- Department of Pharmaceutics, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, United Kingdom.
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3
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Tailoring novel soft nano-vesicles ‘Flexosomes’ for enhanced transdermal drug delivery: Optimization, characterization and comprehensive ex vivo – in vivo evaluation. Int J Pharm 2019; 560:101-115. [DOI: 10.1016/j.ijpharm.2019.01.072] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 01/25/2019] [Accepted: 01/31/2019] [Indexed: 11/18/2022]
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4
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Abstract
Skin hydration is a complex process that influences the physical and mechanical properties of skin. Various technologies have emerged over the years to assess this parameter, with the current standard being electrical probe-based instruments. Nevertheless, their inability to provide detailed information has prompted the use of sophisticated spectroscopic and imaging methodologies, which are capable of in-depth skin analysis that includes structural and composition details. Modern imaging and spectroscopic techniques have transformed skin research in the dermatological and cosmetics disciplines, and are now commonly employed in conjunction with traditional methods for comprehensive assessment of both healthy and pathological skin. This article reviews current techniques employed in measuring skin hydration, and gives an account on their principle of operation and applications in skin-related research.
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Rangsimawong W, Obata Y, Opanasopit P, Ngawhirunpat T, Takayama K. Enhancement of Galantamine HBr Skin Permeation Using Sonophoresis and Limonene-Containing PEGylated Liposomes. AAPS PharmSciTech 2018; 19:1093-1104. [PMID: 29168128 DOI: 10.1208/s12249-017-0921-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 11/07/2017] [Indexed: 11/30/2022] Open
Abstract
This study aimed to investigate the effect of low-frequency sonophoresis (SN) and limonene-containing PEGylated liposomes (PL) on the transdermal delivery of galantamine HBr (GLT). To evaluate the skin penetration mechanism, confocal laser scanning microscopy (CLSM), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC) were employed. The application of SN led to more GLT penetration into and through the skin than GLT solution alone. The liposomes also improved GLT permeation, and 2% limonene-containing PL (PL-LI2%) exhibited the highest GLT permeation, followed by PL-LI1%, PL-LI0.1%, and PL. The CLSM images of PL-LI2% resulted in the highest fluorescence intensity of fluorescent hydrophilic molecules in the deep skin layer, and the rhodamine PE-labeled liposome membrane was distributed in the intercellular region of the stratum corneum (SC). PL-LI2% induced significant changes in intercellular lipids in the SC, whereas SN had no effect on intercellular lipids of the SC. DSC thermograms showed that the greatest decrease in the lipid transition temperature occurred in PL-LI2%-treated SC. SN might improve drug permeation through an intracellular pathway, while limonene-containing liposomes play an important role in delivering GLT through an intercellular pathway by increasing the fluidity of intercellular lipids in the SC. Moreover, a small vesicle size and high membrane fluidity might enhance the transportation of intact vesicles through the skin.
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6
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Hao F, Jin X, Liu QS, Zhou Q, Jiang G. Epidermal Penetration of Gold Nanoparticles and Its Underlying Mechanism Based on Human Reconstructed 3D Episkin Model. ACS APPLIED MATERIALS & INTERFACES 2017; 9:42577-42588. [PMID: 29148696 DOI: 10.1021/acsami.7b13700] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Nanomaterials are widely used in diverse aspects, and their translocation behavior through the skin would be helpful in understanding the corresponding exposure risks. To reveal how surface functionalization of nanoparticles influences the skin penetration, three kinds of gold nanoparticles (GNPs) with negatively, neutrally, and positively charged surfaces, that is, cetyltrimethylammonium bromide-coated GNPs (CTAB@GNP), polyvinylpyrrolidone-coated GNPs (PVP@GNP), and citrate-coated GNPs (Citrate@GNP), were studied using human reconstructed 3D Episkin model. The measurement of Au distribution in diverse layers of the Episkin model indicated that all three GNPs could penetrate through the epidermis, wherein CTAB@GNP with positive surface charges exhibited the highest efficiency in skin penetration. The upward osmosis of the medium proteins confirmed the occurrence of skin permeation induced by GNP treatment, and the lipid network in the stratum corneum was also altered as the consequence of GNP exposure. When compared to Citrate@GNP and PVP@GNP, CTAB@GNP significantly compromised the tight junction of keratinocytes, causing paracellular penetration of nanoparticles. The existence of cytoplasmic gold showed the transcytosis pathway through endocytosis and exocytosis processes was the main epidermic penetration behavior of the tested GNPs. The study on GNP penetration process through the 3D Episkin model has, on one hand, offered a promising approach to evaluate the translocation process of nanoparticles across the skin, and, on the other hand, provided mechanism explanation for diverse penetration behaviors of GNPs with different surface charges. The findings herein would be of great help in nanotechnology improvement and nanosafety evaluation.
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Affiliation(s)
- Fang Hao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences , Beijing 100049, China
| | - Xiaoting Jin
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- Institute of Biomedical Sciences, Shanxi University , Taiyuan 030006, China
| | - Qian S Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences , Beijing 100049, China
| | - Qunfang Zhou
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences , Beijing 100049, China
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences , Beijing 100049, China
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7
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Salimi A, Hedayatipour N, Moghimipour E. The Effect of Various Vehicles on the Naproxen Permeability through Rat Skin: A Mechanistic Study by DSC and FT-IR Techniques. Adv Pharm Bull 2016; 6:9-16. [PMID: 27099831 PMCID: PMC4833885 DOI: 10.15171/apb.2016.03] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 08/31/2015] [Accepted: 12/23/2015] [Indexed: 08/05/2023] Open
Abstract
PURPOSE The purpose of the present investigation was to evaluate the effectiveness of different vehicles on drug permeability and microstructure of intercellular or lipids in SC layer of skin. METHODS Pre-treated skin of rat using some vehicles including Labarac PG ,Transcutol P, tween 80, span 80 and propylene glycol (PG), were mounted on specialized design franz-diffusion cell was used to assess naproxen permeation and parameters such as permeability coefficients and state flux (Jss) were evaluated. Any differences in peak position and also change in symmetric and asymmetric stretching of C-H bond, lipid ester carbonyl stretching in SC, C=O stretching (Amide I) and C-N stretching of keratin (Amide II) absorbance using Fourier transform infrared spectroscopy (FTIR) were considered to investigate the enhancing mechanism. DSC method was utilized to compare their mean transition temperature (Tm) and enthalpies (ΔH). RESULTS Steady-state flux (Jss), permeability coefficient (Kp) and diffusion coefficient (D) were significantly (p<0.05) increased by using their span80 showed the biggest enhancement ratio (ERflux) and Transcutol P, Labrafac PG, Tween 80 and Propylene glycol were at the next levels. In comprised to hydrated rat skin the maximum increase in diffusion coefficient was for Tween 80(p<0.05), Lipid fluidization, lipid disruption structure and the irreversible denaturation of proteins in the SC layer of skin by span 80, Tween 80, Labrafac PG, Transcutol P and propylene glycol, were indicated by FT-IR and DSC techniques. CONCLUSION It is concluded that naproxen permeation through rat skin may be facilitated by utilizing the vehicle systems. Lipid fluidization and lipid extraction are among suggested mechanisms.
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Affiliation(s)
- Anayatollah Salimi
- Nanotechnology Research Center, Department of Pharmaceutics, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Najme Hedayatipour
- Nanotechnology Research Center, Department of Pharmaceutics, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Eskandar Moghimipour
- Nanotechnology Research Center, Department of Pharmaceutics, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
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8
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The influence of surface charge and photo-reactivity on skin-permeation enhancer property of nano-TiO2 in ex vivo pig skin model under indoor light. Int J Pharm 2014; 467:90-9. [DOI: 10.1016/j.ijpharm.2014.03.052] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 03/26/2014] [Accepted: 03/27/2014] [Indexed: 01/08/2023]
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9
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Comparative SAXS and DSC study on stratum corneum structural organization in an epidermal cell culture model (ROC): impact of cultivation time. Eur J Pharm Sci 2013; 50:577-85. [PMID: 23770376 DOI: 10.1016/j.ejps.2013.06.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 06/01/2013] [Accepted: 06/02/2013] [Indexed: 11/20/2022]
Abstract
Cell cultured skin equivalents present an alternative for dermatological in vitro evaluations of drugs and excipients as they provide the advantage of availability, lower variability and higher assay robustness compared to native skin. For penetration/permeation studies, an adequate stratum corneum barrier similar to that of human stratum corneum is, however, a prerequisite. In this study, the stratum corneum lipid organization in an epidermal cell culture model based on rat epidermal keratinocytes (REK organotypic culture, ROC) was investigated by small-angle X-ray scattering (SAXS) in dependence on ROC cultivation time and in comparison to native human and rat stratum cornea. In addition, the thermal phase behavior was studied by differential scanning calorimetry (DSC) and barrier properties were checked by measurements of the permeability of tritiated water. The development of the barrier of ROC SC obtained at different cultivation times (7, 14 and 21 days at the air-liquid interface) was connected with an increase in structural order of the SC lipids in SAXS measurements: Already cultivation for 14 days at the air-liquid interface resulted overall in a competent SC permeability barrier and SC lipid organization. Cultivation for 21 days resulted in further minor changes in the structural organization of ROC SC. The SAXS patterns of ROC SC had overall large similarities with that of human SC and point to the presence of a long periodicity phase with a repeat distance of about 122Å, e.g. slightly smaller than that determined for human SC in the present study (127Å). Moreover, SAXS results also indicate the presence of covalently bound ceramides, which are crucial for a proper SC barrier, although the corresponding thermal transitions were not clearly detectable by DSC. Due to the competent SC barrier properties and high structural and organizational similarity to that of native human SC, ROC presents a promising alternative for in vitro studies, particularly as it can be obtained under overall rather straightforward cell culture conditions and thus low assay costs.
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10
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Williams A. Brian Barry: Innovative Contributions to Transdermal and Topical Drug Delivery. Skin Pharmacol Physiol 2013; 26:234-42. [DOI: 10.1159/000351946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 04/05/2013] [Indexed: 11/19/2022]
Abstract
Brian Barry published over 300 research articles across topics ranging from colloid science, vasoconstriction and the importance of thermodynamics in dermal drug delivery to exploring the structure and organisation of the stratum corneum barrier lipids and numerous strategies for improving topical and transdermal drug delivery, including penetration enhancers, supersaturation, coacervation, eutectic formation and the use of varied liposomes. As research in the area blossomed in the early 1980s, Brian wrote <i>the</i> book that became essential reading for both new and established dermal delivery scientists, explaining the background mathematics and principles through to formulation design. Brian also worked with numerous scientists, as collaborators and students, who have themselves taken his rigorous approach to scientific investigation into their own research groups. This paper can only describe a small fraction of the many significant contributions that Brian made to the field during his 40-year academic career.
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11
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Franzen L, Vidlářová L, Kostka KH, Schaefer UF, Windbergs M. Freeze-drying as a preserving preparation technique forin vitrotesting of human skin. Exp Dermatol 2012; 22:54-6. [DOI: 10.1111/exd.12058] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2012] [Indexed: 11/27/2022]
Affiliation(s)
- Lutz Franzen
- Department of Biopharmaceutics and Pharmaceutical Technology; Saarland University; Saarbruecken; Germany
| | | | - Karl-Heinz Kostka
- Department of Plastic and Hand Surgery; Caritas-Krankenhaus; Lebach; Germany
| | - Ulrich F. Schaefer
- Department of Biopharmaceutics and Pharmaceutical Technology; Saarland University; Saarbruecken; Germany
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12
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Abstract
Stratum corneum, the outermost layer of skin, allows transport of only low-molecular weight (<500) lipophilic solutes. Here, we report a surprising finding that avicins (Avs), a family of naturally occurring glycosylated triterpenes with a molecular weight > 2,000, exhibit skin permeabilities comparable to those of small hydrophobic molecules, such as estradiol. Systematic fragmentation of the Av molecule shows that deletion of the outer monoterpene results in a 62% reduction in permeability, suggesting an important role for this motif in skin permeation. Further removal of the tetrasaccharide residue results in a further reduction of permeability by 79%. These results, taken in sum, imply that synergistic effects involving both hydrophobic and hydrophilic residues may hold the key in facilitating translocation of Avs across skin lipids. In addition to exhibiting high permeability, Avs provided moderate enhancements of skin permeability of estradiol and polysaccharides, including dextran and inulin but not polyethylene glycol.
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13
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Towards drug quantification in human skin with confocal Raman microscopy. Eur J Pharm Biopharm 2012; 84:437-44. [PMID: 23220382 DOI: 10.1016/j.ejpb.2012.11.017] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Revised: 10/10/2012] [Accepted: 11/07/2012] [Indexed: 11/21/2022]
Abstract
Understanding the penetration behaviour of drugs into human skin is a prerequisite for the rational development and evaluation of effective dermal drug delivery. The general procedure for the acquisition of quantitative drug penetration profiles in human skin is performed by sequential segmentation and extraction. Unfortunately, this technique is destructive, laborious and lacks spatial resolution. Confocal Raman microscopy bares the potential of a chemically selective, label free and nondestructive analysis. However, the acquisition of quantitative drug depth profiles within skin by Raman microscopy is impeded by imponderable signal attenuation inside the tissue. In this study, we present a chemical semi-solid matrix system simulating the optical properties of human skin. This system serves as a skin surrogate for investigation of Raman signal attenuation under controlled conditions. Caffeine was homogeneously incorporated within the skin surrogate, and Raman intensity depth profiles were acquired. A mathematical algorithm describing the Raman signal attenuation within the surrogate was derived from these profiles. Human skin samples were incubated with caffeine, and Raman intensity depth profiles were similarly acquired. The surrogate algorithm was successfully applied to correct the drug profiles in human skin for signal attenuation. For the first time, a mathematical algorithm was established, which allows correction of Raman signal attenuation in human skin, thus facilitating reliable drug quantification in human skin by confocal Raman spectroscopy.
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14
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Moghimi HR, Alinaghi A, Erfan M. Investigating the potential of non-thermal microwave as a novel skin penetration enhancement method. Int J Pharm 2010; 401:47-50. [PMID: 20854885 DOI: 10.1016/j.ijpharm.2010.09.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2010] [Accepted: 09/14/2010] [Indexed: 12/01/2022]
Abstract
Microwaves (MW), a part of the electromagnetic spectrum at 0.3-300GHz, affect human body in different ways through its thermal and athermal effects, including fluidization of cell membranes and liquid crystalline systems. Due to presence of such structures in skin barrier, it was decided here to investigate the potential of athermal MW as skin penetration enhancer. In this investigation, nitrofurazone was chosen as the model penetrant and its permeation through rat skin was studied in vitro at 45 and 90min exposure intervals using MW intensities of 3, 15, 30, 60, 120W at 2450MHz. Results revealed that at 30°C and 45min exposure, 3W MW does not affect permeation of nitrofurazone (P=0.148), while higher intensities increased its flux significantly (P<0.05) in a intensity-dependent manner up to 2.7 times. When the duration of exposure increased to 90min, the enhancement ratio also increased to reach a maximum of 3.3. Applying 60W MW at 25, 30, 37 and 42°C resulted in a parabolic relationship between temperature and enhancement ratio. The present results reveal that microwave can act as a skin penetration enhancement method and that its effect depends on applied intensities, exposure time and temperature.
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Affiliation(s)
- Hamid R Moghimi
- School of Pharmacy, Shaheed Beheshti Medical University, Valiasr Ave., Niayesh Junction, P.O. Box 14155-6153, Tehran, Iran.
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15
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Foldvari M, Badea I, Wettig S, Baboolal D, Kumar P, Creagh AL, Haynes CA. Topical delivery of interferon alpha by biphasic vesicles: evidence for a novel nanopathway across the stratum corneum. Mol Pharm 2010; 7:751-62. [PMID: 20349952 DOI: 10.1021/mp900283x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Noninvasive delivery of macromolecules across intact skin is challenging but would allow for needle-free administration of many pharmaceuticals. Biphasic vesicles, a novel lipid-based topical delivery system, have been shown to deliver macromolecules into the skin. Investigation of the delivery mechanism of interferon alpha (IFN alpha), as a model protein, by biphasic vesicles could improve understanding of molecular transport through the stratum corneum and allow for the design of more effective delivery systems. The interaction of biphasic vesicles with human skin and isolated stratum corneum membrane was investigated by confocal microscopy, differential scanning calorimetry (DSC) and small- and wide-angle X-ray scattering (SAXS and WAXS). Confocal microscopy revealed that biphasic vesicles delivered IFN alpha intercellularly, to a depth of 70 microm, well below the stratum corneum and into the viable epidermis. DSC and SAXS/WAXS data suggest that the interaction of biphasic vesicles with SC lipids resulted in the formation of a three-dimensional cubic Pn3m polymorphic phase by the molecular rearrangement of intercellular lipids. This cubic phase could be an intercellular permeation nanopathway that may explain the increased delivery of IFN alpha by biphasic vesicles. Liposomes and submicrometer emulsion (the individual building blocks of biphasic vesicles) separately and methylcellulose gel, an alternative topical vehicle, did not induce a cubic phase and delivered low amounts of IFN alpha below the stratum corneum. Molecular modeling of the cubic Pn3m phase and lamellar-to-cubic phase transitions provides a plausible mechanism for transport of IFN alpha. It is hypothesized that induction of a Pn3m cubic phase in stratum corneum lipids could make dermal and transdermal delivery of other macromolecules also possible.
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Affiliation(s)
- Marianna Foldvari
- School of Pharmacy, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada.
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16
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Infrared spectroscopic study of lipid interaction in stratum corneum treated with transdermal absorption enhancers. Int J Pharm 2010; 389:18-23. [DOI: 10.1016/j.ijpharm.2010.01.007] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Revised: 01/07/2010] [Accepted: 01/08/2010] [Indexed: 11/22/2022]
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17
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Peira E, Chirio D, Carlotti M, Spagnolo R, Trotta M. Formulation studies of microemulsions for topical applications of acyclovir. J Drug Deliv Sci Technol 2009. [DOI: 10.1016/s1773-2247(09)50035-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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18
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Pappinen S, Hermansson M, Kuntsche J, Somerharju P, Wertz P, Urtti A, Suhonen M. Comparison of rat epidermal keratinocyte organotypic culture (ROC) with intact human skin: Lipid composition and thermal phase behavior of the stratum corneum. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:824-34. [DOI: 10.1016/j.bbamem.2007.12.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Revised: 12/19/2007] [Accepted: 12/24/2007] [Indexed: 10/22/2022]
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19
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Becker SM, Kuznetsov AV. Local temperature rises influence in vivo electroporation pore development: a numerical stratum corneum lipid phase transition model. J Biomech Eng 2007; 129:712-21. [PMID: 17887897 DOI: 10.1115/1.2768380] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Electroporation is an approach used to enhance transdermal transport of large molecules in which the skin is exposed to a series of electric pulses. Electroporation temporarily destabilizes the structure of the outer skin layer, the stratum corneum, by creating microscopic pores through which agents, ordinarily unable to pass into the skin, are able to pass through this outer barrier. Long duration electroporation pulses can cause localized temperature rises, which result in thermotropic phase transitions within the lipid bilayer matrix of the stratum corneum. This paper focuses on electroporation pore development resulting from localized Joule heating. This study presents a theoretical model of electroporation, which incorporates stratum corneum lipid melting with electrical and thermal energy equations. A transient finite volume model is developed representing electroporation of in vivo human skin, in which stratum corneum lipid phase transitions are modeled as a series of melting processes. The results confirm that applied voltage to the skin results in high current densities within the less resistive regions of the stratum corneum. The model captures highly localized Joule heating within the stratum corneum and subsequent temperature rises, which propagate radially outward. Electroporation pore development resulting from the decrease in resistance associated with lipid melting is captured by the lipid phase transition model. As the effective pore radius grows, current density and subsequent Joule heating values decrease.
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Affiliation(s)
- S M Becker
- Mechanical and Aerospace Engineering, North Carolina State University, Box 7910, Raleigh, North Carolina 27695, USA.
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20
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Kuntsche J, Bunjes H, Fahr A, Pappinen S, Rönkkö S, Suhonen M, Urtti A. Interaction of lipid nanoparticles with human epidermis and an organotypic cell culture model. Int J Pharm 2007; 354:180-95. [PMID: 17920216 DOI: 10.1016/j.ijpharm.2007.08.028] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2007] [Accepted: 08/13/2007] [Indexed: 10/22/2022]
Abstract
Various lipid nanoparticle formulations were investigated with respect to (trans)dermal drug delivery with special regard to the mechanism of their effects on human and an organotypic cell culture epidermis. Potential alterations of stratum corneum lipid domains were studied using fluorescence assays with labeled liposomes and thermal analysis of isolated stratum corneum. Influences on the permeation of corticosterone were investigated and the occlusive properties of the nanoparticles were determined by measurements of the transepidermal water loss (TEWL). The penetration of a fluorescence dye was visualized by fluorescence microscopy of cross sections of human epidermis after incubation with cubic and solid lipid nanoparticles. Corticosterone permeation was limited when applied in matrix-type lipid nanoparticles (fat emulsion, smectic and solid lipid nanoparticles). An adhesion of solid lipid nanoparticles was clearly observed in thermal analysis as reflected by additional phase transitions probably caused by the nanoparticle matrix lipid. However, as for the other matrix-type nanoparticles, no distinct alterations of the phase transitions of the stratum corneum lipids were observed. Cubic nanoparticles led to the most predominant effect on skin permeation where the surface-active matrix lipid may act as penetration enhancer. An alteration of the stratum corneum lipids' thermal behavior as well as an interaction with fluorescence labeled liposomes was observed. Differences observed in permeation studies and thermal analysis of human and cell culture epidermis indicate that surface lipids, which are not present to the same extent in the cell culture model than in human epidermis, seem to play an important role.
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Affiliation(s)
- Judith Kuntsche
- Department of Pharmaceutics, University of Kuopio, PO Box 1627, FIN-70211 Kuopio, Finland.
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Yadav S, Pinto NG, Kasting GB. Thermodynamics of water interaction with human stratum corneum I: measurement by isothermal calorimetry. J Pharm Sci 2007; 96:1585-97. [PMID: 17238199 DOI: 10.1002/jps.20781] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A thermodynamic study of water interaction with human stratum corneum (SC) is presented. The procedure consisted of conjoint water vapor sorption and heat flow measurements. Heat of sorption of water in excised human SC at various relative humidities was measured in an isothermal calorimeter at 32 degrees C using back and thigh skin from three different donors. These measurements, combined with the gravimetric sorption isotherm, were used to calculate the integral and differential enthalpies and entropies associated with binding of water to SC. Differential enthalpy values suggest hydrogen-bonding interactions similar to those for water in wool keratin. The changes in differential enthalpy and entropy with increasing water content followed a pattern similar to that seen in wool and other hydrophilic polymers. The results are partially interpreted in terms of a BET isotherm with monolayer volume v(m) = 0.022 g H(2)O/g dry SC and binding parameter C = 6.5 x 10(8).
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Affiliation(s)
- Santosh Yadav
- Department of Chemical & Materials Engineering, University of Cincinnati, Cincinnati, Ohio 45221-0012, USA
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22
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Silva CL, Nunes SCC, Eusébio MES, Pais AACC, Sousa JJS. Thermal Behaviour of Human Stratum Corneum. Skin Pharmacol Physiol 2006; 19:132-9. [PMID: 16612140 DOI: 10.1159/000092593] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2005] [Accepted: 07/21/2005] [Indexed: 11/19/2022]
Abstract
PURPOSE To use high-speed differential scanning calorimetry (DSC) in the identification of transitions in human stratum corneum (SC). Several scanning rates (100 degrees C/min to 400 degrees C/min) are used. RESULTS Eight transitions from 0 to 120 degrees C are detected in a significant number of samples. Most of these transitions have already been identified in previous studies, but have been labeled considering essentially that only four are present. Results also indicate some degree of reversibility for transitions occurring at temperatures above 90 degrees C. Dehydrated SC samples displayed slightly more defined transition peaks and a less frequent presence of the transitions below 50 degrees C. In turn, the delipidised SC matrix showed two major endothermic signals, centered around 55 and 100 degrees C, in conjunction with other much less marked features. CONCLUSIONS The interpretation of DSC traces in terms of four main transition temperatures must be complemented having in mind the occurrence of other transitions, some of them at physiological temperatures. This work further suggests that transitions at temperatures above 90 degrees C may to a large degree be associated to lipids, while transition at approx. 55 degrees C is probably related to lipids covalently linked to proteins, as previously suggested.
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Affiliation(s)
- C L Silva
- Faculdade de Farmácia, Universidade de Coimbra, Coimbra, Portugal
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23
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Changez M, Varshney M, Chander J, Dinda AK. Effect of the composition of lecithin/n-propanol/isopropyl myristate/water microemulsions on barrier properties of mice skin for transdermal permeation of tetracaine hydrochloride: In vitro. Colloids Surf B Biointerfaces 2006; 50:18-25. [PMID: 16690263 DOI: 10.1016/j.colsurfb.2006.03.018] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2006] [Revised: 03/13/2006] [Accepted: 03/21/2006] [Indexed: 11/25/2022]
Abstract
Effect of composition of lecithin water-in-oil and oil-in-water microemulsion on in vitro transdermal permeation of tetracaine hydrochloride was studied on mice model. The results were compared with an aqueous solution of tetracaine hydrochloride (2.7 mg/ml). In vitro skin flux and permeability coefficients were obtained using the Franz diffusion cell. Differential scanning calorimetry (DSC), transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM) were used to study the mechanism of action of the microemulsion. Micrographs of TEM and CLSM studies were analyzed by using Image Pro Plus image software. Skin flux of tetracaine hydrochloride was found to be dependent on the composition of lecithin/n-propanol/isopropyl myristate/water microemulsions. At lower Km ratio (i.e. 0.5:1 and 0.8:1) of microemulsion, the rate of permeation of tetracaine hydrochloride was higher when compared to the microemulsion of higher Km ratio (1:1 and 1.5:1). Image analysis of TEM micrograph, 6h after application of lecithin microemulsion, showed 3.5+/-0.75-fold (p<0.001) increase in the intercellular space in the epidermis and 3.8+/-0.4-fold (p<0.001) enhancement in upper dermis. CLMS results show that sweat gland and hair follicles also provided path for permeation of the drug through the skin.
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Affiliation(s)
- Mohammad Changez
- Centre for Biomedical Engineering, Indian Institute of Technology, New Delhi 110016, India.
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24
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Silva CL, Nunes SCC, Eusébio MES, Sousa JJS, Pais AACC. Study of human stratum corneum and extracted lipids by thermomicroscopy and DSC. Chem Phys Lipids 2006; 140:36-47. [PMID: 16480966 DOI: 10.1016/j.chemphyslip.2006.01.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2005] [Revised: 01/06/2006] [Accepted: 01/06/2006] [Indexed: 10/25/2022]
Abstract
A study on the thermal behavior of human stratum corneum and lipids is described. The use of high scanning rate DSC for both SC and extracted lipids allows the consistent determination of transition temperatures, including those of lower energy. Changes are found both at physiological and higher temperatures. There is a clear correspondence between the thermotropic behavior of these two systems. However, one of the transitions found in human SC (approximately 55 degrees C) is absent in extracted lipids and may be ascribed to those covalently-linked to corneocytes. Lipidic thermotropic behavior is clearly found above 100 degrees C, in which proteins do not play an exclusive role. Changes related to most transitions are observed directly by polarized light thermal microscopy in extracted lipids. This technique also allowed for the observation of large segregated domains in the extracted lipids. A drastic change is observed at approximately 60 degrees C, corresponding to the disruption of the lamellar structure.
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Affiliation(s)
- C L Silva
- Faculdade de Farmácia, Universidade de Coimbra, 3004-535 Coimbra, Portugal
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25
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Narishetty STK, Panchagnula R. Effect of L-menthol and 1,8-cineole on phase behavior and molecular organization of SC lipids and skin permeation of zidovudine. J Control Release 2005; 102:59-70. [PMID: 15653134 DOI: 10.1016/j.jconrel.2004.09.016] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2004] [Accepted: 09/17/2004] [Indexed: 11/15/2022]
Abstract
The aim of this investigation was to study the effect of 1,8-cineole and L-menthol on phase behavior and molecular organization of Stratum corneum (SC) lipids and permeation of zidovudine (AZT) across human cadaver skin (HCS). Permeation studies were conducted across HCS using Franz diffusion cells at 37 degrees C. Differential scanning calorimetry (DSC) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) were employed to understand the effect of terpenes on phase behavior and molecular organization of a model SC lipid system consisting of an equimolar mixture of ceramide, palmitic acid and cholesterol. Both 1,8-cineole and L-menthol applied at 5% w/v in 66.6% ethanol as a vehicle significantly enhanced the pseudosteady state flux of AZT across HCS. The vehicle reduced the number of endothermic transitions observed in the DSC thermogram of a hydrated model SC lipid system from three to two with a lowered midtransition temperature (Tm), while the inclusion of terpenes resulted in a single but very broad endothermic transition for the model SC lipid system. Correspondingly, ATR-FTIR studies revealed that both 1,8-cineole and L-menthol increased CH2 stretching frequencies on either side of lipid transition in addition to lowering the Tm of model SC lipid system by approximately 2-8 degrees C. The alterations observed in the amide-I frequencies of model SC lipid system after the inclusion of terpenes suggest that they disrupt the interlamellar hydrogen-bonding network at the polar head group region. Further, terpenes also increased the hydration levels of the lipid system probably by forming new aqueous channels. These results indicate that terpenes enhance transdermal permeation of AZT and other drugs by transforming SC lipids from a highly ordered orthorhombic perpendicular subcellular packing to a less ordered hexagonal subcell packing.
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Affiliation(s)
- Sunil T K Narishetty
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S. Nagar (Punjab), India
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26
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Al-Saidan SM. Transdermal self-permeation enhancement of ibuprofen. J Control Release 2004; 100:199-209. [PMID: 15544868 DOI: 10.1016/j.jconrel.2004.08.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2004] [Accepted: 08/25/2004] [Indexed: 11/17/2022]
Abstract
The objective of this study was to prepare saturated solutions of ibuprofen, of different concentrations, and to investigate their effect on permeation of ibuprofen across rat epidermis. Ibuprofen saturated solutions were prepared using 0.1, 0.2, 0.3 and 0.4 M disodium hydrogen phosphate solution (DHP). The solubility of ibuprofen in DHP increased as the molarity of DHP increased. Thus the four saturated solutions of ibuprofen (0.1M-DHP-IBU, 0.2M-DHP-IBU, 0.3M-DHP-IBU and 0.4M-DHP-IBU) have different concentrations of the same drug, and showed same pH (pH 7.0+/-1). The permeability study was also carried out using human epidermis and silastic membrane. Permeation rate of ibuprofen across rat epidermis and human epidermis from 0.4M-DHP-IBU was much greater than from 0.1M-DHP-IBU. The magnitudes of increase in the drug flux were 46.4-fold with rat epidermis and 9.4-fold with human epidermis. Such a great increase in drug flux was not observed with silastic membrane, only 1.4-fold. This suggests that the increased drug flux is likely due to drug-skin interaction and not the increased concentration of ibuprofen per se. Surface tension (ST) measurements of DHP versus ibuprofen concentration showed ST reduction of DHP, from 72 to 27.9 dyn/cm. This is an indication that ibuprofen acted as ionic surfactant and the observed skin permeability enhancement is attributed to disruption of stratum corneum barrier. Results of DSC study supported this assumption. DSC of untreated rat stratum corneum samples showed lipid transitions at 41.9+/-0.0 degrees C (T1), 55.1+/-1.6 degrees C (T(x)), 70.2+/-0.1 degrees C (T2) and 77.5+/-0.1 degrees C (T3), while those pretreated with 0.4M-DHP-IBU did not show the first three lipid transitions. Also, pretreatment of rat epidermis with 0.4M-DHP-IBU enhanced permeation of diclofenac sodium greater than 1250-fold. This corroborates that ibuprofen not only enhances its own permeation but also that of other drugs, such as diclofenac sodium.
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Affiliation(s)
- S M Al-Saidan
- Department of Pharmaceutics, Faculty of Pharmacy, Kuwait University, P.O. Box 24923, SAFAT 13110, Kuwait.
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Jain AK, Panchagnula R. Effect of temperature on imipramine hydrochloride permeation: role of lipid bilayer arrangement and chemical composition of rat skin. Int J Pharm 2003; 250:287-93. [PMID: 12480294 DOI: 10.1016/s0378-5173(02)00550-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of this investigation was to study the effect of temperature on the permeation of imipramine hydrochloride (IMH) across rat skin from two different vehicles. Differential scanning calorimetry (DSC) was used to characterize the phase transitions of rat epidermis and extracted rat SC lipids, and the transition temperatures were correlated with the permeability of IMH at different temperatures. Permeability of IMH from ethanol and propylene glycol (PG) was determined at five different temperatures and observed that a significant increase in IMH permeability occurred 45 degrees C from both the vehicles. Further, high energies of activation for rat skin permeation suggested that IMH diffuses across intercellular lipid matrix and therefore any change in the packing of SC lipids will have an effect on IMH permeation. Three endotherms T(1), T(2) and T(3) of rat epidermis were observed in DSC thermograms at 44, 53 and 64 degrees C and were assigned as transitions corresponding to orthorhombic to hexagonal, hexagonal to more disordered phase and melting of lipids with high cholesterol content, respectively. The high permeability values of IMH above 45 degrees C were therefore reasoned to be because of orthorhombic to hexagonal phase transition in rat skin from close to that temperature.
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Affiliation(s)
- Amit Kumar Jain
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research, Sector 67, Phase-X, SAS Nagar, Mohali 160 062, Punjab, India
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28
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Sznitowska M, Janicki S, Williams A, Lau S, Stołyhwo A. pH-induced modifications to stratum corneum lipids investigated using thermal, spectroscopic, and chromatographic techniques. J Pharm Sci 2003; 92:173-9. [PMID: 12486693 DOI: 10.1002/jps.10281] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The effects of nonphysiological pH on stratum corneum lipid content and structure have been studied. Human stratum corneum samples were soaked in solutions at pH 1, 2, 6, 11, or 12 for up to 24 h. After removal of the stratum corneum, the buffer solutions were analyzed for lipid composition using thin-layer chromatography analysis and the stratum corneum sheets were examined using differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. The results demonstrate that only buffers of pH 11 or higher affect the stratum corneum lipids. No large difference in the contents of ceramides and cholesterol extracted by buffers of varying pH was observed. In contrast, free fatty acid extraction was pH dependent; amounts removed by 24-h treatment with pH 11 or 12 buffers were comparable, and were similar to amounts extracted with a methanol-chloroform mixture for 15 min. No appreciable changes in DSC and FTIR spectra were detected between untreated stratum corneum and stratum corneum samples treated with buffers at pHs in the range 1-6. For tissue treated with pH 11 and 12, the position of the endothermal melting peak T2 shifted from 72 to 74 degrees C on the DSC thermograms. Small changes in the broadness of spectral peaks at 2855 cm(-1) [attributable to upsilon(CH(2)) stretching of stratum corneum lipids and 1655 cm(-1) upsilon(C=O) stretching amide I band] can be seen in the FTIR spectra from the treated stratum corneum samples, although no shifts in peak positions were observed. Intensity changes in peaks from extraneous lipids [upsilon(C=O) stretching mode at 1735 cm(-1)] were observed after buffer treatments. The changes provoked by the alkaline buffers are not dramatic and it may be concluded that the stratum corneum appears remarkably resilient to extended exposure in both highly acidic (pH 1) and highly alkaline (pH 12) environments.
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Affiliation(s)
- Małgorzata Sznitowska
- Department of Pharmaceutical Technology, Medical University of Gdansk, 80-416 Gdansk, Poland.
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29
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Moss GP, Dearden JC, Patel H, Cronin MTD. Quantitative structure-permeability relationships (QSPRs) for percutaneous absorption. Toxicol In Vitro 2002; 16:299-317. [PMID: 12020604 DOI: 10.1016/s0887-2333(02)00003-6] [Citation(s) in RCA: 160] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Quantitative structure-permeability relationships (QSPRs) have been derived by many researchers to model the passive, diffusion-controlled, percutaneous penetration of exogenous chemicals. Most of these relationships are based on experimental data from the published literature. They indicate that molecular size (as molecular weight) and hydrophobicity (as the logarithm of the octanol-water partition coefficient; log k(ow)) are the main determinants of transdermal penetration. This article reviews the current state of the art in QSPRs for absorption of chemicals through the skin, and where this technology can be exploited in future research. The main shortfalls in QSPR models result from inconsistency and error of the experimental values used to derive them. This is probably caused by the manner in which they employ data from a variety of sources and, in some cases, slightly different experimental protocols. Further, most current models are based on data generated from either aqueous or ethanolic solution, where each penetrant is present at its saturated solubility or a fraction of its saturated solubility. No models currently account for the influences of formulation upon percutaneous penetration. Current QSPR models provide a significant tool for assessing the percutaneous penetration of chemicals. They may be important in determining the bioavailability of a range of topically applied exogenous chemicals, and in issues of dermal toxicology and risk assessment. However, their current use may be limited by their lack of applicability across different formulation types. As a consequence, their true value may be to make predictions within specific formulation types, as opposed to a general model based on a range of formulation types. In addition, the endpoint of models may be inappropriate for specific applications other than the systemic delivery of topically applied chemicals.
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Affiliation(s)
- G P Moss
- School of Pharmacy and Chemistry, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK
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30
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Ford JL, Willson R. Thermal analysis and calorimetry of pharmaceuticals. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s1573-4374(99)80020-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
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