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Li L, Zhang M, Cao Y, Ma P, Wei J, Tao L, Qian K. An LC-MS Method for Determination of Betamethasone in Tissue Engineering Skin and Application to Dermatopharmacokinetic Study. CURR PHARM ANAL 2019. [DOI: 10.2174/1573412914666180831101354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background and Objectives:Tissue engineering skin is a three-dimensional skin substitute cultured in the gas-liquid interface using the immortalized keratinocytes (HaCaT cells). In this study, the preliminary metabolism of betamethasone dipropionate by tissue engineering skin was studied and the pharmacokinetics methodology was established using betamethasone dipropionate gel as the target drug.Methods:The betamethasone dipropionate gel was applied on the tissue engineering skin after the skin was cultured. Then the medium (receiving liquid) and skin were taken on 0.25, 0.75, 1.75, 3, 5, 8, 12, 24, 36, 48 h time points. The betamethasone concentration in the medium and skin was determinated by the LC-MS method. Chromatographic analysis was conducted using isocratic elution on a C18 column (150 mm × 2.0 mm, 5 µm) in mobile phase consisting of methanol and water (70 : 30, v/v). The mobile phase was pumped at a flow rate of 0.2 mL/min.Results:This method exhibited linearity within the concentration range of 0. 1 to 50 µg /mL of betamethasone. The LLOQ was 0. 1 µg /mL. The intra- and inter-day precisions of betamethasone in the blank medium were all less than 10.69 % (RSD, %), while in the blank, skin homogenates were all less than 13.96 % (RSD, %). As a result, the betamethasone concentration in the medium and skin could both be detected, which suggested that betamethasone dipropionate could be metabolized to betamethasone through the tissue engineering skin.Conclusion:It was feasible to use tissue engineering skin as a model to study the dermatopharmacokinetics of topical betamethasone dipropionate gel. The research could build a foundation for the dermato-pharmacokinetic study approach.
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Affiliation(s)
- Lingjun Li
- Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College, No. 12, Jiangwangmiao Street, Nanjing, 210042, China
| | - Mengli Zhang
- Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College, No. 12, Jiangwangmiao Street, Nanjing, 210042, China
| | - Yuping Cao
- Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College, No. 12, Jiangwangmiao Street, Nanjing, 210042, China
| | - Pengcheng Ma
- Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College, No. 12, Jiangwangmiao Street, Nanjing, 210042, China
| | - Jun Wei
- Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College, No. 12, Jiangwangmiao Street, Nanjing, 210042, China
| | - Lei Tao
- Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College, No. 12, Jiangwangmiao Street, Nanjing, 210042, China
| | - Kun Qian
- Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College, No. 12, Jiangwangmiao Street, Nanjing, 210042, China
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Elejalde NR, Butassi E, Zacchino S, Macías MA, Portilla J. Intermolecular interaction energies and molecular conformations in N-substituted 4-aryl-2-methylimidazoles with promising in vitro antifungal activity. ACTA CRYSTALLOGRAPHICA SECTION B-STRUCTURAL SCIENCE CRYSTAL ENGINEERING AND MATERIALS 2019; 75:1197-1207. [DOI: 10.1107/s2052520619013271] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 09/27/2019] [Indexed: 11/10/2022]
Abstract
A convenient one-pot synthesis of 4-aryl-2-methyl-N-phenacylimidazoles (4) through a microwave-assisted pseudo-tricomponent reaction of α-bromoacetophenones (1) with acetamidine hydrochloride (2) is reported. Ketones (4) were successfully used as substrates for the preparation of the respective N-(2-hydroxyethyl)imidazoles (5) with yields up to 87%. The synthesized compounds were characterized by NMR and high-resolution mass spectrometry analyses, and several structures were confirmed and studied by single-crystal X-ray diffraction. The analysis of the whole-of-molecule interactions shows that, despite the difference in the atom–atom contacts forming the crystals, dispersion energies make the largest contribution to the formation of the solids, giving an isotropic tendency in the topology of the energy framework diagrams for pairs of molecules. In addition, the in vitro antifungal activity of both families of compounds [ketones (4) and alcohols (5)] against Candida albicans and Cryptococcus neoformans was evaluated, where the 2,4-dichlorophenyl-substituted alcohol (5f), an isomer of the drug miconazole, showed the highest activity (IC50 = 7.8 µg ml−1 against C. neoformans).
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3
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Macías MA, Elejalde NR, Butassi E, Zacchino S, Portilla J. Studies via X-ray analysis on intermolecular interactions and energy frameworks based on the effects of substituents of three 4-aryl-2-methyl-1H-imidazoles of different electronic nature and their in vitro antifungal evaluation. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2018; 74:1447-1458. [PMID: 30398201 DOI: 10.1107/s2053229618014109] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Accepted: 10/05/2018] [Indexed: 11/11/2022]
Abstract
The crystal structures of 2-methyl-4-phenyl-1H-imidazole, C10H10N2, (3a), 4-(4-chlorophenyl)-2-methyl-1H-imidazole hemihydrate, C10H9ClN2·0.5H2O, (3b), and 4-(4-methoxyphenyl)-2-methyl-1H-imidazole, C11H12N2O, (3c), have been analyzed. It was found that the electron-donating/withdrawing tendency of the substituent groups in the aryl ring influence the acid-base properties of the 2-methylimidazole nucleus, changing the strength of the intermolecular N-H...N interactions. This behaviour not only influences the crystal structure but also seems to have an important effect on the antifungal activity. Considering the substituent groups, that is, H in (3a), Cl in (3b) and OMe in (3c), the formation of strong N-H...N connections has the probability (3a) > (3b) > (3c), while compound (3c) proves to be more active than (3a) and (3b) at all concentrations against C. neoformans.
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Affiliation(s)
- Mario A Macías
- Department of Chemistry, Universidad de los Andes, Cra. 1 N 18-A-12, 111711, Bogotá, Colombia
| | - Nerith Rocio Elejalde
- Bioorganic Compounds Research Group, Department of Chemistry, Universidad de los Andes, Carrera 1 No. 18A 10, Bogotá 111711, Colombia
| | - Estefanía Butassi
- Pharmacognosy Area, Faculty of Biochemical and Pharmaceutical Sciences, Universidad Nacional de Rosario, Suipacha 531, 2000-Rosario, Argentina
| | - Susana Zacchino
- Pharmacognosy Area, Faculty of Biochemical and Pharmaceutical Sciences, Universidad Nacional de Rosario, Suipacha 531, 2000-Rosario, Argentina
| | - Jaime Portilla
- Bioorganic Compounds Research Group, Department of Chemistry, Universidad de los Andes, Carrera 1 No. 18A 10, Bogotá 111711, Colombia
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4
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Elejalde N, Macías M, Castillo J, Sortino M, Svetaz L, Zacchino S, Portilla J. Synthesis and
in vitro
Antifungal Evaluation of Novel
N
‐Substituted 4‐Aryl‐2‐methylimidazoles. ChemistrySelect 2018. [DOI: 10.1002/slct.201801238] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Nerith‐Rocio Elejalde
- Departamento de QuímicaUniversidad de los Andes Carrera 1 N° 18 A-12, Bogotá Colombia
| | - Mario Macías
- Departamento de QuímicaUniversidad de los Andes Carrera 1 N° 18 A-12, Bogotá Colombia
| | - Juan‐Carlos Castillo
- Departamento de QuímicaUniversidad de los Andes Carrera 1 N° 18 A-12, Bogotá Colombia
| | - Maximiliano Sortino
- Pharmacognosy AreaFaculty of Biochemical and Pharmaceutical Sciences.Universidad Nacional de Rosario Suipacha 531 2000-Rosario Argentina
| | - Laura Svetaz
- Pharmacognosy AreaFaculty of Biochemical and Pharmaceutical Sciences.Universidad Nacional de Rosario Suipacha 531 2000-Rosario Argentina
| | - Susana Zacchino
- Pharmacognosy AreaFaculty of Biochemical and Pharmaceutical Sciences.Universidad Nacional de Rosario Suipacha 531 2000-Rosario Argentina
| | - Jaime Portilla
- Departamento de QuímicaUniversidad de los Andes Carrera 1 N° 18 A-12, Bogotá Colombia
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5
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Knezevic NN, Tverdohleb T, Nikibin F, Knezevic I, Candido KD. Management of chronic neuropathic pain with single and compounded topical analgesics. Pain Manag 2017; 7:537-558. [PMID: 29125423 DOI: 10.2217/pmt-2017-0020] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The goal of our review was to emphasize important aspects that physicians should take into consideration when prescribing topical analgesics as part of chronic neuropathic pain treatment. We discuss the dermatopharmacokinetics and microstructural components of the skin, differences between topical and transdermal drug delivery, and topical medication effects on peripheral neuropathy and central sensitization. Even though the US FDA approved topical analgesics are 8%-capsaicin and 5%-lidocaine patches for treating postherpetic neuralgia, there are many other studies conducted on the efficacy of topical ketamine cream, clonidine gel, topical gabapentin, topical baclofen and topical phenytoin for peripheral neuropathic pain, either alone or in combination with other formulations. Furthermore, we discuss new compounded topical analgesics that are becoming more popular and that are showing promising results in the management of chronic peripheral neuropathies. However, more studies are needed for elucidation of the role of topical analgesics and their effects, especially when combined with other treatments.
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Affiliation(s)
- Nebojsa Nick Knezevic
- Department of Anesthesiology, Advocate Illinois Masonic Medical Center, Chicago, IL 60657, USA.,Department of Anesthesiology, University of Illinois, Chicago, IL 60612, USA.,Department of Surgery, University of Illinois, Chicago, IL 60612, USA
| | - Tatiana Tverdohleb
- Department of Anesthesiology, Advocate Illinois Masonic Medical Center, Chicago, IL 60657, USA
| | - Farid Nikibin
- Department of Anesthesiology, Advocate Illinois Masonic Medical Center, Chicago, IL 60657, USA
| | - Ivana Knezevic
- Department of Anesthesiology, Advocate Illinois Masonic Medical Center, Chicago, IL 60657, USA
| | - Kenneth D Candido
- Department of Anesthesiology, Advocate Illinois Masonic Medical Center, Chicago, IL 60657, USA.,Department of Anesthesiology, University of Illinois, Chicago, IL 60612, USA.,Department of Surgery, University of Illinois, Chicago, IL 60612, USA
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6
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Manian M, Madrasi K, Chaturvedula A, Banga AK. Investigation of the Dermal Absorption and Irritation Potential of Sertaconazole Nitrate Anhydrous Gel. Pharmaceutics 2016; 8:E21. [PMID: 27399763 PMCID: PMC5039440 DOI: 10.3390/pharmaceutics8030021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 06/06/2016] [Accepted: 06/24/2016] [Indexed: 12/02/2022] Open
Abstract
Effective topical therapy of cutaneous fungal diseases requires the delivery of the active agent to the target site in adequate concentrations to produce a pharmacological effect and inhibit the growth of the pathogen. In addition, it is important to determine the concentration of the drug in the skin in order to evaluate the subsequent efficacy and potential toxicity for topical formulations. For this purpose, an anhydrous gel containing sertaconazole nitrate as a model drug was formulated and the amount of the drug in the skin was determined by in vitro tape stripping. The apparent diffusivity and partition coefficients were then calculated by a mathematical model describing the dermal absorption as passive diffusion through a pseudo-homogenous membrane. The skin irritation potential of the formulation was also assessed by using the in vitro Epiderm™ model. An estimation of the dermal absorption parameters allowed us to evaluate drug transport across the stratum corneum following topical application. The estimated concentration for the formulation was found to be higher than the MIC100 at the target site which suggested its potential efficacy for treating fungal infections. The skin irritation test showed the formulation to be non-irritating in nature. Thus, in vitro techniques can be used for laying the groundwork in developing efficient and non-toxic topical products.
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Affiliation(s)
- Mahima Manian
- Department of Pharmaceutical Sciences, College of Pharmacy, Mercer University, Atlanta, GA 30341, USA.
| | - Kumpal Madrasi
- Department of Pharmacy Practice, College of Pharmacy, Mercer University, Atlanta, GA 30341, USA.
| | - Ayyappa Chaturvedula
- Department of Pharmacy Practice, College of Pharmacy, Mercer University, Atlanta, GA 30341, USA.
- Department of Pharmacotherapy, University of North Texas Health Science Center, Fort Worth, Texas 76107, USA.
| | - Ajay K Banga
- Department of Pharmaceutical Sciences, College of Pharmacy, Mercer University, Atlanta, GA 30341, USA.
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7
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Erdő F, Hashimoto N, Karvaly G, Nakamichi N, Kato Y. Critical evaluation and methodological positioning of the transdermal microdialysis technique. A review. J Control Release 2016; 233:147-61. [DOI: 10.1016/j.jconrel.2016.05.035] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 05/10/2016] [Accepted: 05/13/2016] [Indexed: 01/28/2023]
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8
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Nair AB, Singh K, Al-Dhubiab BE, Attimarad M, Harsha S, Alhaider IA. Skin uptake and clearance of ciclopirox following topical application. Biopharm Drug Dispos 2014; 34:540-9. [PMID: 24123146 DOI: 10.1002/bdd.1866] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 09/10/2013] [Accepted: 10/08/2013] [Indexed: 11/07/2022]
Abstract
The assessment of skin uptake and clearance are important to determine the efficiency and systemic safety of dermatological formulations. The objective of this study was to assess the skin uptake, clearance and possible systemic delivery of ciclopirox following topical application in Wistar rats. In vitro studies (3 h) were carried out in excised pig skin to assess the permeation and retention capacity of ciclopirox in skin layers using gel formulations (1% and 2% w/v). In vivo dermatopharmacokinetics (DPK) parameters were determined by measuring the drug levels in the skin as a function of time post application (0.5, 1, 1.5 and 2 h) and post removal (3, 4, 6 and 8 h) of the formulation in Wistar rats. The plasma drug concentrations were also determined in the same animals. In vitro data indicate the low permeability and high retention of ciclopirox in the stratum corneum. The DPK data observed indicate a higher Cmax value (175.43 ± 25.62 μg/cm2) and AUC (632.14 ± 102.26 μg.h/cm2) with the 2% (w/v) gel formulation. Further, the skin elimination of ciclopirox follows first order kinetics with a short half-life (t1/2 ~2 h). The fraction of drug reaching the systemic circulation was found to be significantly low (~0.15% of the applied dose). A relation between the drug concentration in the skin layers and the plasma was observed with a short lag period. The topical availability of ciclopirox was found to be relatively low and endured rapid clearance with minimal systemic uptake.
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9
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Russell LM, Guy RH. Measurement and prediction of the rate and extent of drug delivery into and through the skin. Expert Opin Drug Deliv 2009; 6:355-69. [DOI: 10.1517/17425240902865561] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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10
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N'Dri-Stempfer B, Navidi WC, Guy RH, Bunge AL. Improved bioequivalence assessment of topical dermatological drug products using dermatopharmacokinetics. Pharm Res 2008; 26:316-28. [PMID: 18941872 DOI: 10.1007/s11095-008-9742-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Accepted: 10/02/2008] [Indexed: 11/24/2022]
Abstract
PURPOSE A dermatopharmacokinetic (DPK) approach, in which drug levels in the stratum corneum (SC) are measured as a function of time post-application and post-removal of the product using tape-strip sampling in vivo in humans, has been considered for the comparative assessment of topical bioavailability. Its application to-date has been limited by contradictory results and concerns that variability in the method necessitates large numbers of treatment sites and volunteers. The objective of this study was to test whether a revised protocol could better assess bioequivalence. METHODS A blinded study of three 1% econazole nitrate cream products, for which the SC is the site of action, was conducted to examine several modifications to the DPK methodology. In addition to protocol changes designed to reduce experimental variability, bioequivalence was assessed at a single uptake time and a single clearance time measured in duplicate in each subject. RESULTS Conclusive determinations of bioequivalence were achieved with only four treatment sites per product in each of 14 volunteers, which was less than one-third the number required in a previous DPK investigation. CONCLUSIONS Comparative bioequivalence can be assessed conclusively with fewer treatment sites in fewer subjects with robust methods that should be less sensitive to inter-laboratory differences.
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Affiliation(s)
- Berthe N'Dri-Stempfer
- Chemical Engineering Department, Colorado School of Mines, 1500 Illinois Street, Golden, Colorado 80401, USA
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11
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Navidi W, Hutchinson A, N'Dri-Stempfer B, Bunge A. Determining bioequivalence of topical dermatological drug products by tape-stripping. J Pharmacokinet Pharmacodyn 2008; 35:337-48. [PMID: 18465213 DOI: 10.1007/s10928-008-9091-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2007] [Accepted: 04/22/2008] [Indexed: 10/22/2022]
Abstract
The maximum level of drug in the stratum corneum (C(max)) and the area under the curve of drug level in the stratum corneum versus time (AUC) have been proposed as metrics for assessing bioequivalence of topical drugs. These metrics, which require that concentrations be measured at eight or more times, were developed for drugs that are absorbed into the bloodstream, and are less appropriate for topical drugs. Concentrations of topical drugs are measured by tape-stripping, and it is difficult to make a large number of precise measurements due to the limited amount of available skin. We present a new method (the two-time method) for assessing bioequivalence of topical drugs. The method involves some modifications to standard tape-stripping methodology, designed to reduce the variability in measured drug levels. Perhaps most importantly, drug levels are measured at only two times, one during the uptake phase and one during the clearance phase. Measuring concentrations at only two times allows replicate measurements to be made, which increases efficiency. We compared the performance of the two-time method with a standard method through a simulation study that uses a model based on real data. When two drugs are in fact bioequivalent, the two-time method requires only 20 subjects to achieve the efficiency of a standard study with 50 subjects. In a situation in which two drugs are bioinequivalent, the two-time method requires only 30 subjects to achieve the efficiency of a standard study with 100 subjects.
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Affiliation(s)
- William Navidi
- Mathematical and Computer Sciences, Colorado School of Mines, Golden, CO 80401, USA.
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12
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N'Dri-Stempfer B, Navidi WC, Guy RH, Bunge AL. Optimizing metrics for the assessment of bioequivalence between topical drug products. Pharm Res 2008; 25:1621-30. [PMID: 18449629 DOI: 10.1007/s11095-008-9577-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2007] [Accepted: 03/25/2008] [Indexed: 10/22/2022]
Abstract
PURPOSE Stratum corneum tape stripping post-application of a drug product followed by analysis of the active agent in this tissue layer is an approach being seriously considered for the comparative assessment of topical bioavailability. Key issues revolve around how best to perform this experiment and interpret the data. METHODS Using previously published results from a comparative study of three 0.025% tretinoin gel products, alternative data analysis approaches are presented that may render the technique more accessible to the evaluation of new and generic topical dosage forms. RESULTS For the tretinoin gel study, the conclusions for bioequivalence from measurements of drug levels at only one uptake and one clearance time were the same as those from the original study, which required measurements at eight different treatment times. Furthermore, comparisons of drug levels at one uptake and one clearance time discriminated differences in bioequivalence for clearance and uptake, which had previously been missed. Half-life estimates, derived from time course data of drug clearance, can be related to lag time for drug penetration through the SC. CONCLUSIONS This new data analysis demonstrates that comparative bioequivalence might be assessed more easily.
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Affiliation(s)
- Berthe N'Dri-Stempfer
- Chemical Engineering Department, Colorado School of Mines, 1500 Illinois Street, Golden, Colorado 80401, USA
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13
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Chik Z, Johnston A, Tucker AT, Burn RT, Perrett D. Validation and application of capillary electrophoresis for the analysis of lidocaine in a skin tape stripping study. Biomed Chromatogr 2007; 21:775-9. [PMID: 17497758 DOI: 10.1002/bmc.823] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A fast and simple capillary zone electrophoresis method was developed and validated for the determination of lidocaine in skin using tape samples. Separation was performed in a 350 mm (265 mm to window) x 50 microm i.d. fused silica capillary using a background electrolyte of phosphoric acid-Tris pH 2.5. The extraction of lidocaine from tape samples was achieved using methanol, which was diluted to 50% with water before injection. Procaine was the internal standard. The migration times for procaine and lidocaine were 2.9 and 3.2 min, respectively. The limit of quantification for lidocaine was 50 microg, with signal to noise ratio greater than 10. The calibration curve was linear from 50 to 1000 microg with r(2) greater than 0.99. The CV for both within- and between-assay imprecision and the percentage of inaccuracy for the quality control samples including lower and upper limits of quantitation were <or=2% and <or=14%, respectively. The absolute recovery of lidocaine was >97%. The accuracy and selectivity of this method allowed the measurement of lidocaine in tape samples obtained from a skin tape stripping study of local anesthetics in healthy subjects.
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Affiliation(s)
- Z Chik
- Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur
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14
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Pershing LK, Nelson JL, Corlett JL, Briggs GB, Still KR, Jederberg WW. Disposition and pharmacokinetics of a lubricant contaminant, 2,6-di-tert-butyl 4-nitrophenol, in grafted human skin. J Appl Toxicol 2006; 26:402-9. [PMID: 16835940 DOI: 10.1002/jat.1153] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Disposition and uptake/elimination profiles of topical 2,6-di-t-butyl, 4-nitrophenol (DBNP), the nitrated metabolite of an antioxidant additive of lubricant and hydraulic fluids was quantified in human skin grafted on athymic mice after a single topical 75 microg dose in corn oil. DBNP was quantified throughout the stratum corneum (SC), epidermis (E) and dermis (D) in punch biopsies collected from treated skin 0.5, 1, 2, 4, 8 and 24 h after application. SC samples were harvested from the treated skin with 20 adhesive discs. E and D were generated from the biopsy using a manual sectioning method. Detectable DBNP concentrations were measured in all skin compartments at all time points investigated. The Cmax of DBNP in SC was 1663 +/- 602 microg cm(-3), and approximately 30 and approximately 300 fold greater than the Cmax for E and D, respectively. Tmax occurred at 1.0, 0.5 and 1.0 in the SC, E and D, respectively. Over a 24 h interval (AUC0-24 h) there was 52 and 520 fold more DBNP in the SC than E and D, respectively. The elimination half-life of DBNP was 11 h from the SC and 9 h from both E and D. Thus, DBNP was quickly absorbed into the outermost layer of skin and established a steep concentration profile through human skin. The data are consistent with the vast majority of DBNP remaining on the surface (77%) or within human skin (15%) in vivo with only 0.2% of the DBNP dose quantified in the systemic blood circulation.
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Affiliation(s)
- Lynn K Pershing
- Department of Dermatology, University of Utah, Salt Lake City, UT 84132, USA.
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15
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Pershing LK, Reilly CA, Corlett JL, Crouch DJ. Effects of vehicle on the uptake and elimination kinetics of capsaicinoids in human skin in vivo. Toxicol Appl Pharmacol 2004; 200:73-81. [PMID: 15451310 DOI: 10.1016/j.taap.2004.03.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2004] [Accepted: 03/30/2004] [Indexed: 10/26/2022]
Abstract
While the physiologic and molecular effects of capsaicinoids have been extensively studied in various model systems by a variety of administration routes, little is known about the uptake and elimination kinetic profiles in human skin following topical exposure. The present study evaluated the uptake and elimination kinetics of capsaicinoids in human stratum corneum following a single topical exposure to 3% solutions containing 55% capsaicin, 35% dihydrocapsaicin, and 10% other analogues prepared in three vehicles: mineral oil (MO), propylene glycol (PG), and isopropyl alcohol (IPA). Capsaicinoid solutions were evaluated simultaneously in a random application pattern on the volar forearms of 12 subjects using a small, single 150-microg dose. Capsaicin and dihydrocapsaicin were recovered from human skin using commercial adhesive discs to harvest stratum corneum from treated sites. Capsaicinoids were extracted from the stratum corneum-adhesive discs and quantified by liquid chromatography/mass spectroscopy (LC/MS). Both capsaicinoids were detected in stratum corneum 1 min after application with all vehicles and achieved a pseudo-steady state shortly thereafter. IPA delivered three times greater capsaicin and dihydrocapsaicin into the human stratum corneum than PG or MO at all time points investigated. The Cmax of capsaicin in IPA, PG, and MO was 16.1, 6.2, and 6.5 microg, respectively. The dihydrocapsaicin content was 60% of capsaicin with all vehicles. The estimated T(half) of capsaicin and dihydrocapsaicin in the three vehicles was similar (24 h). Thus, maximal cutaneous capsaicinoid concentrations were achieved quickly in the human stratum corneum and were concentration and vehicle dependent. In contrast, capsaicinoid half-life was long and vehicle independent.
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Affiliation(s)
- Lynn K Pershing
- Department of Dermatology, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
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Tsai JC, Cheng CL, Tsai YF, Sheu HM, Chou CH. Evaluation of in vivo bioequivalence methodology for topical clobetasol 17-propionate based on pharmacodynamic modeling using Chinese skin. J Pharm Sci 2004; 93:207-17. [PMID: 14648650 DOI: 10.1002/jps.10536] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The United States Food and Drug Administration recommends pilot dose duration-response and pivotal bioequivalence studies to be conducted using reflectance colorimetry for assessment of the in vivo bioequivalence of topical dermatologic corticosteroids. The major objectives of the present studies were to examine the applicability of the standardized pharmacodynamic modeling-based methodology to super-potent clobetasol 17-propionate (CP) in the Chinese population and to evaluate the bioequivalence of two generic ointments and four generic creams containing 0.05% (w/w) CP with respect to Dermovate formulations using such methodology. In the pilot dose duration-response study, although the E(max) model (where E(max) is the maximum fitted value of AUEC, which is the area under the baseline-corrected, untreated control-site-corrected a* scale data from 0 to 24 h after drug removal) did not provide acceptable model fits, E(max) parameter estimates of -38.97 +/- 3.62 and -41.89 +/- 11.28 a*-scale. h, and ED(50) (dose duration required to achieve 50% of the fitted E(max) value) estimates of 0.40 +/- 0.37 and 0.42 +/- 0.16 h were obtained for Dermovate ointment and cream, respectively, by population analyses. The estimates for the two formulations were not statistically different, so in vivo bioequivalence studies were conducted at an ED(50)dose duration of approximately 0.5 h for both Dermovate formulations. The results demonstrated that one generic ointment was bioequivalent to Dermovate, whereas the other was not. None of the generic creams were shown to be bioequivalent to Dermovate cream. The in vivo bioequivalence data from the vasoconstriction assay were linearly correlated with stratum corneum uptake of the drug at the same dose duration until the maximal vasoconstriction response was achieved. The studies illustrated the applicability of the standardized pharmacodynamic modeling-based methodology in detecting the product differences between a variety of generic 0.05% CP formulations and reference Dermovate formulations in Chinese skin.
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Affiliation(s)
- Jui-Chen Tsai
- Institute of Clinical Pharmacy, College of Medicine, National Cheng Kung University, Tainan, 1 University Road, Tainan, Taiwan 70101.
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Pershing LK, Nelson JL, Corlett JL, Shrivastava SP, Hare DB, Shah VP. Assessment of dermatopharmacokinetic approach in the bioequivalence determination of topical tretinoin gel products. J Am Acad Dermatol 2003; 48:740-51. [PMID: 12734504 DOI: 10.1067/mjd.2003.175] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND A new dermatopharmacokinetic (DPK) approach has been proposed for bioequivalence determination of topical drug products by comparing the drug content kinetics in stratum corneum. OBJECTIVE We sought to establish any correlation between clinical safety/efficacy and DPK approach in bioequivalence determination of tretinoin gel 0.025%. METHODS Tretinoin and isotretinoin were quantified in human volar forearm stratum corneum as a function of time with 3 tretinoin gel 0.025% products in 49 patients. Stratum corneum layers were harvested using multiple adhesive disks, which were subsequently extracted and quantified for both isomers by high-performance liquid chromatography. RESULTS Products with similar composition and therapeutic equivalence were found bioequivalent, and products with different composition and clinical profiles were found bioinequivalent by DPK methodology. CONCLUSIONS There is a direct correlation between DPK parameters in healthy patients and clinical safety/efficacy of tretinoin gel products in patients with acne. Data support the use of DPK parameters and methodology in the bioequivalence assessment of topical tretinoin gel products.
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Affiliation(s)
- Lynn K Pershing
- Department of Dermatology, University of Utah, Salt Lake City, 84132, USA.
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