Journal of

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Transdermal drug delivery (TDD) is a non-invasive, topical administration method for therapeutic agents. Transdermal delivery also has advantages including providing release for long periods of time, improving patient compliance, and generally being inexpensive. Despite these advantages, the use of TDD has been limited by innate barrier functions of the skin. Only small (<500 Da), lipophilic molecules can passively diffuse through the skin. As a result of the barrier function of the skin, passive transdermal delivery has primarily been limited to small molecules. The skin, which consists of several layers including the stratum corneum, other epidermal layers, and dermis, is the primary defense system of the body. The main barrier to therapeutic delivery is the outermost layer of the skin, the stratum corneum. As a result, various methods of skin permeabilization have been explored for their ability to enhance the transport of drugs across the stratum corneum. Scientists evaluated new drug delivery systems such as nano-carriers and drug delivery systems and enhancer methods such as penetration enhancers. The purpose of drug delivery systems are to deliver sufficient drug molecules into the skin with maximum stability and minimal toxicity. To guarantee successful transdermal drug delivery, a drug delivery system must exhibit several essential properties including drug protection, targeted drug delivery, biocompatibility and biodegradability.

This paper reviews transdermal drug delivery systems, recent enhancement techniques to optimize drug delivery such as microneedles and especially vesicular systems.  Herein, we focus on the differences in their composition, physico-chemical properties and applications of those drug delivery systems. We hope recent innovations can work as a foundation for further research and development in transdermal drug delivery system.

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Diseases of the skin can cause harm and emotional distress  in patients. The desirable  drug is one with least complications and most effectiveness. By prolongation of target exposure, drug effectiveness could be improved. There are several suggested solutions, including the use of chemical enhancers, electroporation, iontophoresis, and the use of nanoparticles as carriers of pharmaceutical agents. The use of various nanostructures, including liposomes, dendrimers, autosomes, and many mineral nanoparticles, have been proposed to prevent the limitations  with conventional formulations. Topical drug delivery has many benefits, including  using high concentrations of the drug and reducing  systemic passage of medicament. Many skin products, such as Estrasorb, Diractin and Aczone are available in the market with new and different manufacturing techniques for more skin penetration.
This paper introduces new approaches to drug delivery, types of nanocomposites and methods for increasing the penetration of pharmaceutical agents in the skin. Various factors such as physicochemical properties and the size of nanoparticles, as well as the effects of manipulation on the surface of these particles, have been discussed.

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Background and Aim: Drug delivery through the microneedle array has been considered as an easy and non-invasive method in recent years. The purpose of this study was to design and construct an array of biodegradable polymeric microneedles containing Amphotericin-B to introduce this system and its use in the treatment of cutaneous lesions caused by Leishmania major parasite inoculation as a model in skin infections.

Methods: In this study, microneedles were fabricated by three-step molding method, which included master mold making, polymeric matrix that blending of polyvinyl pyrrolidine and methacrylic acid and finally casting.

Results: The identification of Amphotericin-B in polymeric microscopic compositions was investigated by absorption and emission spectroscopy. Also, the mechanical strength of microneedles, which confirms their ability to penetrate the skin, was investigated by a transducer.

Conclusion: In this study, the design and fabrication of a skin-permeable polymeric microneedle array with biodegradability and biocompatibility characteristics in physiological environment was performed. Using the properties of designed needles, loading of Amphotericin-B was used for the treatment of leishmaniasis and skin fungal infections.