Enhancement Of Transdermal Absorption Research Articles

Transdermal Absorption Enhancement of Cosmetic Ingredients into the Stratum Corneum by Multi Spike Moist Pulse

皮膚に有用な美容成分の浸透を電気刺激で促進させる手法は種々しられている。われわれは，美容成分の角層への浸透を高める電気浸透波形6種類の角層への浸透量の違いについてアニオン性を有するリン酸アスコルビルMgとカチオン性傾向のナイアシンアミドの2種類の美容成分を用いて比較検討した。その結果，このたび開発したエレクトロポレーション要素と高周波要素を併せもつ複合浸透波形がきわめて浸透量が多いことが示された。（1）イオントフォレーシスはコントロールに比べ浸透量が多い傾向であり従来の報告と一致するものであったが有意差は見られなかった。また高周波（RF）もコントロールに比べ浸透量が多い傾向ではあったもののリン酸アスコルビルMgでは有意差は見られなかった。（2）複合浸透波形と同一の出力電力である矩形波と比較したところ，複合浸透波形は矩形波に比べ有意に浸透量が多いことから複数の要素を併せもつ複合浸透波形が角層への浸透を顕著に促進することが明らかになった。

A theoretical investigation on the synergetic effect of hydrogen-bonding interactions and thermodynamic property in the 1: 2 (azacyclopentane-2-one: N-methylolacetamide) ternary complex.

Using chemical penetration enhancers to improve the penetration effect is one kind of important strategies in transdermal drug delivery system. Azone is a widely used transdermal absorption enhancer for transdermal drug delivery. To shed light on the permeation-promoting mechanism of azone, we selected ternary systems formed by azacyclopentane-2-one and N-methylolacetamide (1: 2) and explored the synergetic effect of hydrogen-bonding interactions among them and their thermodynamic properties. The findings indicate that the synergetic effects can enhance the ability of azone to change the original conformation of ceramides and even break the original hydrogen bonds, which is more beneficial for azone to destroy the 3D network structure of ceramides. When azone interacts with ceramide, the order of action tends to interact with one molecule of ceramide first and then with another molecule of ceramide. The synergetic effects of hydrogen-bonding interactions in ternary systems were computed at the B3LYP/6-311 + + G** and MP2(full)/6-311 + + G** levels. Thermodynamic parameters for two ternary-complex routes were worked out at the B3LYP/aug-cc-pVDZ level. The shift of the electron density occurring simultaneously with trimer formation was analyzed at the MP2(full)/6-311 + + G** level. The above calculations were carried out using the Gaussian 03 program packages. Atoms in molecules (AIM) method and the AIMPAC program showed the topological charge density at the MP2(full)/6-311 + + G** level. The synergetic effects of hydrogen-bonding interactions and thermodynamic property in the 1: 2 (azacyclopentane-2-one: N-methylolacetamide) ternary systems were investigated using the B3LYP and MP2(full) methods.

Homoharringtonine is a transdermal granular permeation enhancer

Although modulation of claudin-1-based tight junction (TJ) in stratum granulosum is an option for transdermal absorption of drugs, granular permeation enhancers have never been developed. We previously found that homoharringtonine (HHT), a natural alkanoid, weakened intestinal epithelial barrier with changing expression and cellular localization of TJ components such as claudin-1 and claudin-4. In the present study, we investigated whether HHT is an epidermal granular permeation enhancer. Treatment of normal human epidermal keratinocytes (NHEK) cells with HHT decreased claudin-1 and claudin-4 but not zonula occludens-1 and E-cadherin. HHT lowered TJ-integrity in NHEK cells, accompanied by permeation-enhancement of dextran (4 kDa) in a dose-dependent manner. Transdermal treatment of mice with HHT weakened epidermal barrier. HHT treatment enhanced transdermal absorption of dextran with a molecular mass of up to 10 kDa. Together, HHT may be a transdermal absorption enhancer.

A case of medicine in disguise: motion sickness patches sold as medical devices containing active pharmaceutical substances.

A case study is reported on anti-motion sickness transdermal patches sold in the Internet, claiming to contain only natural ingredients but, actually, containing undeclared medicinal active substances. The visual inspection of the samples evidenced many inconsistencies in secondary and primary packaging, missing of various legal information and a non-compliant "CE" mark. The qualitative analysis was performed by liquid chromatography - high resolution mass spectrometry and the quantitative by liquid chromatography with diode array detector. The analyses evidenced the presence of the antihistaminic drug Diphenhydramine and of other active substances (Capsaicin, a transdermal absorption enhancer, and Diclofenac in traces, probably a contaminant from other productions of the same plant). Moreover, the presence of several trace elements, including those potentially toxic to humans, was assessed by ICP-MS analysis. The case discussed is a new case of "medicines in disguise" never reported in literature, and shows the presence of tangible risks for public health.

Effect of herbal cake-partitioned moxibustion on Leptin/JAK2/STAT3 in lipid-lowering pathway of hyperlipidemia rabbits

Objective: To observe the lipid-lowering effect of different transdermal absorption enhancers applied to the herbal cake-partitioned moxibustion in hyperlipidemia model rabbits, and to explore the possible mechanism. Methods: Forty New-Zealand rabbits were randomly divided into 5 groups using the random number table method, with 8 rats in each group. Rabbits in the blank group were fed routinely with normal diet; rabbits in the other groups were fed with high-fat diet for 12 weeks to establish the hyperlipidemia model. Rabbits in the blank and the model groups were not treated. After the model was prepared, rabbits in the non-transdermal absorption enhancer group received herbal cake-partitioned moxibustion without transdermal absorption enhancer; rabbits in the laurocapram group and the borneol group received herbal cake-partitioned moxibustion with laurocapram or borneol respectively. After 4 weeks of treatment, serum was collected for enzyme-linked immunosorbent assay (ELISA), and the liver tissues were isolated for immunohistochemistry, quantitative polymerase chain reaction (qPCR) and Western-blotting (WB) detection. Results: Serum ELISA results showed that leptin was significantly decreased in the model group compared with the blank group (P 0.05). The qPCR results of rabbit liver tissues showed that the mRNA expressions of leptin, Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) in the model group were significantly lower than those in the blank group (all P<0.05); compared with the model group, the mRNA expressions of leptin, leptin receptor (LR), JAK2 and STAT3 in the non-transdermal absorption enhancer, the laurocapram and the borneol groups were significantly increased (all P<0.05); compared with the non-transdermal absorption enhancer group, the mRNA expressions of leptin, LR, JAK2 and STAT3 in the laurocapram and the borneol groups were significantly increased (all P<0.05); compared with the laurocapram group, the mRNA expressions of leptin, LR, JAK2 and STAT3 in the borneol group were significantly increased (P<0.05). The trend of immunohistochemistry and WB detection results was basically consistent with the qPCR assay results. The immunohistochemistry and WB detection results of phosphorylated JAK2 (phospho-JAK2) and phosphorylated STAT3 (phospho-STAT3) were basically consistent with those of JAK2 and STAT3. Conclusion: The molecular expression of Leptin/JAK2/STAT3 pathway in the hyperlipidemia model rabbits was decreased. The molecular expression of Leptin/JAK2/STAT3 pathway was significantly increased after the herbal cake-partitioned moxibustion. The application of laurocapram and borneol, as transdermal absorption enhancers, in the herbal cake-partitioned moxibustion could more obviously up-regulate the factors of the Leptin/JAK2/STAT3 lipid-regulating pathway than the herbal cake-partitioned moxibustion alone.

Self-Dissolving Microneedle Arrays for Transdermal Absorption Enhancement of Human Parathyroid Hormone (1-34).

Human parathyroid hormone (1-34) (PTH) has been widely used as the subcutaneous injection formulation for the treatment of osteoporosis. In the present study, we developed an efficient transdermal delivery system of PTH by using dissolving microneedle arrays (MNs) composed of hyaluronic acid (HA) for the treatment of osteoporosis. PTH-loaded MNs, with needle length 800 µm, were fabricated via a micro-molding method. The stability of PTH in MNs was found to be 6-fold higher than that of PTH solution when stored at room temperature (15–20 °C) for one month. Micron-scale pores were clearly visible in rat skin following application of PTH-loaded MNs. PTH-loaded MNs were completely dissolved by 60 min following application to rat skin. The bioavailability (BA) of PTH relative to subcutaneous injection was 100 ± 4% following application of PTH-loaded MNs in rats. In addition, PTH-loaded MNs were found to effectively suppress decreases in bone density in a rat model of osteoporosis. Furthermore, no skin irritation was observed at the site of application in rats. These findings indicate that our dissolving MNs have a potential use in formulations for the transdermal delivery of PTH and for the treatment of osteoporosis.

Physical and chemical properties, percutaneous absorption-promoting effects of exopolysaccharide produced by Bacillus atrophaeus WYZ strain

A high yield of exopolysaccharides bacteria isolated from mangrove system was identified as Bacillus atrophaeus by 16S rDNA and named as WYZ strain. An exopolysaccharide (BPS) was obtained from this strain after purification with a yield of about 0.58 g/L. Then some physical and chemical properties of BPS, such as weight average molecular weight (Mw), monosaccharide composition, intrinsic viscosity and water retention capacity were studied. The microstructure (SEM) showed that BPS was porous wound three-dimensional spider web structure. Using BPS as transdermal absorption enhancer, and lidocaine as a test drug, in vitro and local anesthesia in live animals experiments were conducted to explore that the BPS promote lidocaine transdermal absorption and mechanism. In conclusion, the BPS had good water retention capacity and transdermal absorption promoting effect, all of these indicated that BPS has great potential in the field of biomaterials.

Influence of Newly-Developed Transdermal Absorption Enhancer on the Skin Structure

Influence of Newly-Developed Transdermal Absorption Enhancer on the Skin Structure

Transdermal Delivery Enhancement of Gel Containing Niosomes Loaded with Volvariella Volvacea Extract

Our previous study demonstrated the potent in vitro collagen biosynthesis stimulating and antioxidant activities of Volvariella volvacea extract. This study was performed the loading of V. volvacea extract (VV) in niosomes (NV). The physicochemical characterization of the VV loaded niosomes and gel containing niosome of the extract (GNV) was studied. Rat skin transdermal absorption by Franz diffusion cells at 6 hours of NV, GNV was compared with V. Volvacea extract solution (SV). GNV and NV showed higher chemical stability of total phenolic contents than SV. NV exhibited negative zeta potential values with the mean size of 254±20.32 nm. Both GNV and NV retarded the cumulative amounts and fluxes of the total phenolic in the extract in the first hour of skin permeation, while enhanced the skin permeation at the 6 th hour in the experiment. GNV gave the highest percentages of the total phenolic content through rat skin to the receiving solution followed by NV and SV, respectively. This study has demonstrated the potential of gel containing niosomes of the V. volvacea extract appeared to be the suitable system for topical anti-aging application of V. volvacea extract because of the enhancement of chemical stability and rat skin transdermal absorption of V. volvacea extract.

DIMETILSULFOKSID SEBAGAI ENHANCER TRANSPOR TRANSDERMAL TEOFILIN SEDIAAN GEL

Dimethylsulfoxide (DMSO) has been intensively studied the 19th century. This substance is used as a medicine and solve. It can also be used as an absorption enhancer of various drugs, either synthetical or herbal medicines. This study conducted with DMSO as transdermal absorption enhancer of theophylline, which often used as an anti-cellulite dosage forms. The experiments studied in vitro transdermal absorption of theophylline in gel dosage forms, containing 7% theophylline dan various concentration of DMSO i.e. 0% , 3%, 5% and 7% DMSO respectively. These studies used skin membrane of Wistar strain male rats in a vertical type diffusion Cell. The results indicated that DMSO was very potential as a permeation enhancer theophylline, the formula containing 7% DMSO increased the theophylline transport from 17,9 µg to 139,1 µg.

Development and characterization of a novel controlled release drug delivery system based on nanostructured lipid carriers gel for meloxicam

AimThe main objective of the current investigation was to develop nanostructured lipid carriers (NLC) based gel for the enhancement of transdermal absorption of meloxicam (MLX) to achieve local as well as systemic drug action without concurrent gastrointestinal toxicity. Main methodsNLC gel containing MLX was prepared and characterized for particle size, polydispersity, zeta potential, pH, rheology, entrapment efficiency, occlusion factor, and thermal behavior. In vitro drug release, in vitro skin permeation and deposition studies were carried out using Franz diffusion cells. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) of MLX-NLC gel treated stratum corneum (SC) were undertaken to get an insight into the skin permeation enhancement mechanism of MLX-NLC gel. Toxicity potential of the developed gel formulation was assessed by in vitro hemolysis and histopathological examinations. The rat paw edema test was performed to evaluate the anti-inflammatory activity of MLX-NLC gel. Key findingsMLX-NLC gel demonstrated sustained release and enhanced the skin permeation and deposition of meloxicam especially into the dermis in comparison to meloxicam gel (control). MLX-NLC had an impact on the barrier properties of the skin and acted via protein and lipid modifications in the stratum corneum. MLX-NLC gel turned out to be hemocompatible, non-irritant, and non toxic with significant anti-inflammatory activity. SignificanceThe results suggest that NLC gel could be a promising carrier for the transdermal delivery of meloxicam.

Potent enhancement of transdermal absorption and stability of human tyrosinase plasmid (pAH7/Tyr) by Tat peptide and an entrapment in elastic cationic niosomes

Enhancement of transdermal absorption through rat skin and stability of the human tyrosinase plasmid (P) using Tat (T) and an entrapment in elastic cationic niosomes (E) were described. E (Tween61:cholesterol:DDAB at 1:1:0.5 molar ratio) were prepared by the freeze-dried empty liposomes (FDELs) method using 25% ethanol. TP was prepared by a simple mixing method. TPE was prepared by loading T and P in E at the T:P:E ratio of 0.5:1:160 w/w/w. For gel formulations, P, TP, PE and TPE were incorporated into Carbopol 980 gel (30 µg of plasmid per 1 g of gel). For the transdermal absorption studies, the highest cumulative amounts and fluxes of the plasmid in viable epidermis and dermis (VED) were observed from the TPE of 0.31 ± 0.04 µg/cm2 and 1.86 ± 0.24 µg/cm2/h (TPE solution); and 4.29 ± 0.40 µg/cm2 and 25.73 ± 2.40 µg/cm2/h (TPE gel), respectively. Only plasmid from the PE and TPE could be found in the receiving solution with the cumulative amounts and fluxes at 6 h of 0.07 ± 0.01 µg/cm2 and 0.40 ± 0.08 µg/cm2/h (PE solution); 0.10 ± 0.01 µg/cm2 and 0.60 ± 0.06 µg/cm2/h (TPE solution); 0.88 ± 0.03 µg/cm2 and 5.30 ± 0.15 µg/cm2/h (PE gel); and 1.02 ± 0.05 µg/cm2 and 6.13 ± 0.28 µg/cm2/h (TPE gel), respectively. In stability studies, the plasmid still remained at 4 ± 2 °C and 25 ± 2 °C of about 48.00–65.20% and 27.40–51.10% (solution); and 12.34–38.31% and 8.63–36.10% (gel), respectively, whereas at 45 ± 2 °C, almost all the plasmid was degraded. These studies indicated the high potential application of Tat and an entrapment in elastic cationic niosomes for the development of transdermal gene delivery system.

Transdermal absorption enhancement of papain loaded in elastic niosomes incorporated in gel for scar treatment

Papain is one of the protease enzymes from Carica papaya latex which is widely used in dermatology for scar treatment. The aim of this study was to compare the penetration of papain from gel formulations containing niosomes and nanospheres loaded with papain. The vesicular sizes of all niosomes and nanospheres in the gel formulations were in the range of 220.7–520.2nm. Papain loaded in elastic niosomes and incorporated in gel exhibited the accumulate amounts and fluxes of 0.226mg/cm2 and 0.029mg/cm2/h in the whole rat skin and 0.220mg/cm2 and 0.037mg/cm2/h in the receiving solution, which were 3.10, 2.38 and 2.24, 2.25; 10.08, 7.78 and 4.92, 4.93; 4.86, 3.71 and 7.38, 7.38 times more than that from gel containing papain loaded in non-elastic niosomes, PLGA nanospheres and in solution, respectively, investigated by Franz diffusion cells at 6h. All gel formulations incorporated with papain loaded in niosomes and nanospheres gave no irritation on rabbit skin. Gel containing papain loaded in elastic niosomes gave superior chemical stability to gel containing free papain of 1.13, 1.29 and 1.35 times when stored at 4±2, 27±2 and 45±2°C after 3months, respectively. After 28days of application, gel containing papain loaded in elastic niosomes (GEN) exhibited higher reduction of hypertrophic scars of the induced scar on rabbits’ ears determined by a vernier caliper than gel base (GB), gel containing free papain (GS), and gel containing papain loaded in non-elastic niosomes (GNN) of 10.20, 2.73 and 2.31 times, respectively. For histological examination, the numbers of collagen fibres and the height of the scars treated with GEN were significantly decreased compared with the control group. This study has demonstrated the potential of niosomes, especially the elastic niosomes, for the enhancement of rat skin transdermal absorption of papain and the improvement of scar reduction in rabbit ear model which will be beneficial for the development of topical products for scar treatment.

In vivo enhancement of transdermal absorption of ketotifen by supersaturation generated by amorphous form of the drug

The enhancing effect of supersaturation generated by amorphous ketotifen in silicone pressure-sensitive adhesive matrices (PSA) on the transdermal absorption was evaluated in vivo using hairless rats, and it was compared with the increase of drug amount in skin tissues. The duration of the enhancing effect was also investigated in relation to the time how long supersaturation was maintained in PSA. PSA containing crystalline ketotifen (PSA-Crystalline) and that containing amorphous ketotifen (PSA-Amorphous) were prepared by the solvent casting method using n-hexane and dichloromethane, respectively. In vivo transdermal absorption was evaluated by measuring the amount of ketotifen in PSAs, the stratum corneum, and viable skin tissues after administration of PSAs on abdominal sites of hairless rats. The amount of ketotifen absorbed into the systemic circulation was calculated by subtracting the drug amount in whole skin tissues from the amount of the drug released from PSAs, then it was monitored for up to 23h. In both types of PSA, a constant absorption rate was maintained for up to 23h after 7-h lag time. The enhancement factor of PSA-Amorphous against PSA-Crystalline was approximately 7, which was in good agreement with the difference of drug amount in viable skin tissues. Time course of the drug amount in PSA-Amorphous suggested that the supersaturated level was gradually decreased after 10h, but the decline of the driving force from PSAs was supplemented by the drug release from the skin depot resulting in the constant absorption rate up to 23h. These results suggest the usefulness of amorphous ketotifen to obtain enhanced transdermal absorption.

Transdermal absorption and stability enhancement of salmon calcitonin by Tat peptide

Context: Highly organized structure of stratum corneum (SC) is the major barrier of the delivery of macromolecules such as proteins and peptides across the skin. Recently, cell penetrating peptides (CPPs) such as HIV1-trans-activating transcriptional (Tat) have been used to enhance the topical delivery of proteins and peptides. Objective: This study aimed to enhance the transdermal absorption and chemical stability of salmon calcitonin (sCT) by co-incubation with Tat. Materials and methods: Tat-sCT mixture at 1:1 molar ratio was prepared. Transdermal absorption and chemical stability of the mixture was evaluated in comparing with free sCT. Results: Tat-sCT mixture gave higher cumulative amounts and fluxes of sCT than free sCT. The maximum percentage of sCT of 58.36 ± 12.33% permeated into the receiving chamber was found in Tat-sCT mixture at 6 h which was 3.50 folds of free sCT. Tat-sCT mixture demonstrated better sCT stability than sCT solution after 1 month storage at 4°C, 25°C and 45°C. Discussion: The positively-charged arginine groups in Tat might be responsible for the binding of peptide complexes to negatively charged cell surfaces by electrostatic interactions and also the translocation of sCT through the excised skin. Conclusion: This study demonstrated the enhancements of transdermal absorption and stability of sCT by Tat peptide with potential for further application in transdermal delivery of other therapeutic peptides.

Enhancement of Chemical Stability and Transdermal Absorption of Salmon Calcitonin Loaded in Elastic Niosomes

Enhancement of Chemical Stability and Transdermal Absorption of Salmon Calcitonin Loaded in Elastic Niosomes

Enhancement and mechanism of transdermal absorption of terpene-induced propranolol hydrochloride

For the purpose of efficient and safe transdermal administration of propranolol hydrochloride (PHCl), effects of (+)-borneol, (+)-camphor, and α-bisabolol (5 w/v%) in 66.6% ethanol solution on transdermal permeation across rat skin in vitro and their enhancement mechanism was investigated with fourier transform infrared spectroscopy, differential scanning calorimetry, and PHCl-stratum corneum binding studies. Each of (+)-borneol, (+)-camphor, and α-bisabolol significantly increased the transdermal flux of PHCl through rat skin in comparison to the control. The enhancement mechanism of the terpenes is involved with disruption of the lipid bilayer and increase of PHCl partitioning coefficient to the stratum corneum. As for α-bisabolol, the protect effect of skin from dehydration and an important reason of irritation incident were observed with differential scanning calorimetry for the first time.

Transdermal Absorption Enhancement of N-Terminal Tat–GFP Fusion Protein (TG) Loaded in Novel Low-Toxic Elastic Anionic Niosomes

Elastic anionic niosomes (Tween 61/cholesterol/dicetyl phosphate at 1:1:0.05 molar ratio of 20 mM) with various concentrations of ethanol and edge activators sodium cholate (NaC) and sodium deoxycholate (NaDC) showed larger vesicular size (171.94 ± 63.52 - 683.17 ± 331.47 nm) and higher negative zeta potential (-6.45 ± 2.76 to - 17.40 ± 2.51 mV) than the nonelastic anionic niosomes. The elasticity (deformability index) and entrapment efficiency of all elastic vesicles except the NaDC vesicles were higher than the nonelastic vesicles. The morphology, under transmission electron microscope, of elastic and nonelastic niosomes loaded and not loaded with Tat-green fluorescent protein fusion protein (TG) were in large unilamellar structure. TG loaded in elastic (1 mol% NaC) anionic niosomes gave the highest cell viability both in HT-29 (92.32 ± 3.82%) and KB cells (96.62 ± 5.96%), the highest cumulative amounts (62.75 ± 2.68 μg/cm(2) ) and fluxes (10.46 ± 3.45 μg/cm(2) h) in receiving chamber in rat skin transdermal study by Franz diffusion cells. This study has not only indicated the synergistic enhancement effects of the Tat peptide and the niosomal delivery system on the cellular uptake and transdermal absorption of TG but also 1 mol% NaC as an edge activator to obtain a novel low-toxic elastic anionic niosomes for topical use of therapeutic macromolecules such as proteins, as well.

Transdermal absorption enhancement of gel containing elastic niosomes loaded with gallic acid from Terminalia chebula galls

Objectives: To investigate transdermal absorption enhancement of gel containing elastic niosomes loaded with gallic acid in the semipurified fraction isolated from Terminalia chebula Retz. (Combretaceae) galls.Materials and methods: Nonelastic and elastic niosomes loaded with gallic acid in pure form or in the semipurified fraction were developed. Rat skin permeation by vertical Franz diffusion cells of gallic acid from various gel formulations containing elastic niosomes loaded with gallic acid or the semipurified fraction was performed.Results: Elastic and nonelastic niosomes loaded with gallic acid or the semipurified fraction exhibited the mixture of unilamellar and multilamellar structures with negative zeta potential values and in the size range of 200–400 nm. Both loaded elastic and nonelastic niosomes showed good physical and chemical stability for 3 months. The percentages remaining of gallic acid in nonelastic were slightly higher than in elastic niosomes. Both elastic and nonelastic niosomes retarded rat skin permeation of the loaded pure gallic acid, while enhanced the loaded gallic acid in the semipurified fraction. However, elastic niosomes exhibited higher percentages of gallic acid through rat skin than the nonelastic niosomes.Discussion and conclusion: This study has demonstrated the potential of niosomes, especially elastic niosomes, for the enhancement of chemical stability and rat skin transdermal absorption of gallic acid in the semipurified fraction from T. chebula galls, which will be beneficial for topical antiaging application.

Enhancement of Transdermal Absorption, Gene Expression and Stability of Tyrosinase Plasmid (pMEL34)-Loaded Elastic Cationic Niosomes: Potential Application in Vitiligo Treatment

The pMEL34 was loaded in elastic cationic niosomes (Tween61/Cholesterol/DDAB at 1:1:0.5 molar ratio) by chloroform film method with sonication and rehydrated with 25% ethanol. The amount of pMEL34 was determined by gel electrophoresis and gel documentation. The maximum loading of pMEL34 in elastic cationic niosomes was 150 microg/16 mg of the niosomal compositions. At 8 weeks, the remaining plasmid in the elastic niosomes kept at 4 +/- 2 degrees C, 27 +/- 2 degrees C were 49.75% and 38.57%, respectively, whereas at 45 +/- 2 degrees C, all plasmids were degraded. For transdermal absorption through rat skin investigated by Franz diffusion cells at 6 h, the fluxes of pMEL34 loaded in elastic and nonelastic niosomes in viable epidermis and dermis (VED) were 0.022 +/- 0.00 and 0.017 +/- 0.01 microg/cm(2)/h, respectively, whereas only pMEL34 loaded in elastic cationic noisome was observed in the receiver solution. The pMEL34 loaded in elastic cationic niosomes showed the highest tyrosinase gene expression demonstrating higher tyrosinase activity than the free and the loaded plasmid in nonelastic niosomes of about four times. This study has suggested the potential application of elastic cationic niosomes as an efficient topical delivery for tyrosinase gene in vitiligo therapy.