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Franz Diffusion Cells (franz + diffusion_cell)
Selected AbstractsIn vitro permeation of diclofenac sodium from novel microemulsion formulations through rabbit skinDRUG DEVELOPMENT RESEARCH, Issue 1 2005Gülten Kantarc Abstract In order to increase topical penetration of the nonsteroidal anti-inflammatory drug, diclofenac sodium, new microemulsion formulations were prepared to increase drug solubility and in vitro penetration of the drug. The influence of dimethyl sulfoxide and propylene glycol were also investigated as enhancers on the in vitro penetration of diclofenac sodium using Franz diffusion cells using excised dorsal rabbit skin. Factorial randomized design was performed to analyze the results of in vitro permeation studies. Microemulsions prepared with isopropyl alcohol were superior to those prepared with propanol. Enhancers had different effects depending on the formulation. Propylene glycol was superior to dimethyl sulfoxide when incorporated into isopropyl alcohol microemulsion, whereas dimethyl sulfoxide was superior to propylene glycol in propanol microemulsions. There were no observable histopathological differences between the skin of the control group and the treated groups at the light microscope level due to swelling of the skin tissue. The present study shows that microemulsion formulations containing isopropyl alcohol as co-surfactant and propylene glycol as enhancer represent a promising approach for a topical vehicle for diclofenac sodium. Drug Dev. Res. 65:17,25, 2005. © 2005 Wiley-Liss, Inc. [source] Bilayered nail lacquer of terbinafine hydrochloride for treatment of onychomycosisJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 10 2010H.N. Shivakumar Abstract The present study aimed to develop bilayered nail lacquer of terbinafine hydrochloride (TH) for treatment of onychomycosis. The composite nail lacquer formed an underlying drug-loaded hydrophilic layer and overlying hydrophobic vinyl layer. The hydrophilic lacquer made of hydroxylpropyl methylcellulose E-15 contained polyethylene glycol 400 (PEG 400) as a drug permeation enhancer. The vinyl lacquer was composed of poly (4-vinyl phenol) as a water-resistant film former. In vitro permeation studies in Franz diffusion cells indicated that the amount of TH permeated across the human cadaver nail in 6 days was 0.32,±,0.14, 1.12,±,0.42, and 1.42,±,0.53,µg/cm2 from control (hydrophilic lacquer devoid of PEG 400), monolayer (hydrophilic lacquer alone), and bilayered nail lacquers, respectively. A higher nail drug load was seen in vitro with the bilayered lacquer (0.59,±,0.13,µg/mg) as compared to monolayer (0.36,±,0.09,µg/mg) and control (0.28,±,0.07,µg/mg) lacquers. The drug loss despite multiple washing was significantly low (p,<,0.001) for the bilayered lacquer owing to the protective vinyl coating. Clinical studies demonstrated the efficacy of bilayered lacquer to achieve better drug load in the nail plate (1.27,±,0.184,µg/mg) compared to monolayer (0.67,±,0.18,µg/mg) and control (0.21,±,0.04,µg/mg) lacquers. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:4267,4276, 2010 [source] Design of improved permeation enhancers for transdermal drug deliveryJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2009Srinivas S. Godavarthy Abstract One promising way to breach the skin's natural barrier to drugs is by the application of chemicals called penetration enhancers. However, identifying potential enhancers is difficult and time consuming. We have developed a virtual screening algorithm for generating potential chemical penetration enhancers (CPEs) by integrating nonlinear, theory-based quantitative structure,property relationship models, genetic algorithms, and neural networks. Our newly developed algorithm was used to identify seven potential CPE molecular structures. These chemical enhancers were tested for their toxicity on (a) mouse embryonic fibroblasts (MEFs) with MTT assay, and (b) porcine abdominal skin by histology using H/E staining at the end of a 48-h exposure period to the chemicals. Further, melatonin permeability in the presence of the enhancers was tested using porcine skin and Franz diffusion cells. Careful toxicity tests showed that four of the seven "general" CPEs were nontoxic candidate enhancers (menthone, 1-(1-adamantyl)-2-pyrrolidinone, R(+)-3-amino-1-hydroxy-2-pyrrolidinone, and 1-(4-nitro-phenyl)-pyrrolidine-2,5-dione). Further testing of these four molecules as potential melatonin-specific CPEs revealed that only menthone and 1-dodecyl-2-pyrrolidinone provided sufficient enhancement of the melatonin permeation. The results from our permeability and toxicity measurements provide validation of the efficacy and ability of our virtual screening algorithm for generating potential chemical enhancer structures by virtual screening algorithms, in addition to providing additional experimental data to the body of knowledge. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4085,4099, 2009 [source] Delivery of nerve growth factor to brain via intranasal administration and enhancement of brain uptakeJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 10 2009Siva Ram Kiran Vaka Abstract The main objective of the study was to investigate the efficacy of chitosan to facilitate brain bioavailability of intranasally administered nerve growth factor (NGF). In vitro permeability studies and electrical resistance studies were carried out across the bovine olfactory epithelium using Franz diffusion cells. The bioavailability of intranasally administered NGF in rat hippocampus was determined by carrying out brain microdialysis in Sprague,Dawley rats. The in vitro permeation flux across the olfactory epithelium of NGF solution without chitosan (control) was found to be 0.37,±,0.06 ng/cm2/h. In presence of increasing concentration of chitosan (0.1%, 0.25%, and 0.5%, w/v) the permeation flux of NGF was found to be 2.01,±,0.12, 3.88,±,0.19, and 4.12,±,0.21 ng/cm2/h respectively. Trans-olfactory epithelial electrical resistance decreased ,34.50,±,4.06% in presence of 0.25% (w/v) chitosan. The Cmax in rats administered with 0.25% (w/v) chitosan and NGF was 1008.62,±,130.02 pg/mL, which was significantly higher than that for rats administered with NGF only 97.38,±,10.66 pg/mL. There was ,14-fold increase in the bioavailability of intranasally administered NGF with chitosan than without chitosan. Chitosan can enhance the brain bioavailability of intranasally administered NGF. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:3640,3646, 2009 [source] Tocopheryl acetate disposition in porcine and human skin when administered using lipid nanocarriersJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 6 2010Mojgan Moddaresi Abstract Objectives Assessing the delivery of a drug into the skin when it has been formulated within a nanocarrier is a complex process that does not conform to the conventions of traditional semi-solid formulations. The aim of this study was to gain a fundamental understanding of drug disposition in both human and porcine skin when applied using a lipidic nanocarrier. Methods A model system was generated by loading tocopheryl acetate into a well-characterised solid lipid nanoparticle and formulating this system as a traditional aqueous hyaluronic acid gel. Franz diffusion cells fitted with a silicone or nylon membrane were used to assess drug and particle transport independently whilst human and pig skin were employed to determine skin delivery. Key findings The tocopheryl acetate, when loaded into the solid lipid nanoparticles, did not release from the particle. However, 1.65 ± 0.90% of an infinite dose of tocopheryl acetate penetrated into the stratum corneum of pig skin when delivered using a nanoparticle-containing gel. Conclusions These results suggest that hydration of the stratum corneum in pig skin could lead to the opening of hydrophilic pores big enough for 50 nm-sized particles to pass into the superficial layers of the skin, a phenomenon that was not repeated in human skin. [source] Skin permeation of retinol in Tween 20-based deformable liposomes: in-vitro evaluation in human skin and keratinocyte modelsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 2 2006Yu-Kyoung Oh To develop a more effective transdermal delivery method for lipophilic functional cosmetic compounds such as retinol, we formulated various deformable liposomes and compared their transdermal delivery efficiency with those of neutral or negatively-charged conventional liposomes. We tested the deformability of liposomes containing edge activators such as bile salts, polyoxyethylene esters and polyoxyethylene ethers. As indicators of deformability, we used the passed volume and phospholipid ratios during extrusion, as well as the deformability index. We found that the type of edge activator significantly affected the extent of deformability, and that Tween 20 provided the highest level of deformability. Accordingly, we used Tween 20 to formulate deformable liposomes containing retinol in the membrane bilayers, and conducted a skin permeation study in Franz diffusion cells, using dermatomed human skin and three-dimensional human keratinocyte layers. As compared with the use of conventional neutral or negatively-charged liposomes, the use of Tween 20-based deformable liposomes significantly increased the skin permeation of retinol. These results suggested that deformable liposomes might be of potential use for the formulation of retinol and other lipophilic functional cosmetic compounds. [source] Dermal delivery of desmopressin acetate using colloidal carrier systemsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2005Melkamu Getie Recently, the transdermal route has received attention as a promising means to enhance the delivery of drug molecules, particularly peptides, across the skin. In this work, the skin penetration profiles of desmopressin acetate from a colloidal system (water-in-oil microemulsion) and an amphiphilic cream, a standard formulation, were determined using Franz diffusion cells and compared. In the case of the microemulsion, the total percentages of dose obtained from different skin layers (stratum corneum to subcutaneous tissue) were 3.30 ± 0.67, 7.37 ± 2.43 and 15.54 ± 2.72 at 30, 100 and 300 min, respectively. Similarly, 5.19 ± 0.96, 8.04 ± 0.97 and 14.4 ± 5.15% of the dose applied was extracted from the skin treated with the cream. About 6% of the applied dose reached the acceptor compartment from the microemulsion instead of 2% from the cream within 300 min. The concentration of drug that penetrated into the upper layers of the skin was higher from the cream than from the microemulsion at all time intervals. On the other hand, a higher amount of drug was found in the deeper skin layers and in the acceptor compartment from the microemulsion. 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