The final aim/target of Pharmaceutical Sciences is to design successful dosage forms for effective therapy, considering individual patient needs and compliance. Development of new drug entities, particularly using peptides and proteins, is growing in importance and attracting increased interest, as they are specifically effective at a comparably low dose. These very potent and specific peptides and proteins can now be produced in large quantities due to increased knowledge and advancements in biotechnological and pharmaceutical applications. A number of peptide and protein products are now available on the market, and numerous studies investigating them have been published in the literature. Although many peptide/protein like products are generally designed for parenteral administration, some other noninvasive routes have also been used. For example, desmopressin is delivered nasally and deoxyribonuclease by inhalation. Although peptides and proteins are generally orally inactive, cyclosporine is an exception. In order to design and develop long-acting, more effective peptide/protein drugs, the controlled release mechanisms and effective parameters need to be understood and clarified. Therefore, we review herein various peptide/protein delivery systems, including biodegradable and nondegradable microspheres, microcapsules, nanocapsules, injectable implants, diffusion- controlled hydrogels and other hydrophilic systems, microemulsions and multiple emulsions, and the use of iontophoresis or electroporation, and discuss the results of recent researches.

The study was aimed to evaluate the effectiveness of Rosmarinic acid (RA) loaded ethosomes (ETHs) and liposomes (LPs) when subjected to the transdermal application. RA-loaded ETHs and LPs were prepared, optimized and characterized. The ex vivo permeation studies of formulations using mouse abdominal skin were performed. Antioxidant activities and the inhibitory effects of formulations on collagenase and elastase enzymes were measured. Optimized ethosomal formulation (F3) was showed nanometric size range (138 ± 1.11 nm) and greatest entrapment (55 ± 1.80%), was selected for further transdermal permeation studies. Skin permeation profile of the nanoformulations analyzed by HPLC revealed an enhanced permeation of ETHs. Transdermal flux of ETHs was found to be higher than RA solution and LPs. Enzyme inhibitions of ETHs were significant difference found between ETHs and LPs (p < 0.05). ETHs were found to be more effective and successful than LPs. Results suggest that ETHs are more effective than LPs for transdermal delivery of RA.

In this study, drug carrier properties through skin and penetration enhancement effects of carbon nanotubes (CNTs) are presented. Multi-walled and double-walled carbon nanotubes were used. Penetration enhancement into the skin following passive diffusion and iontophoresis were determined. Possible solubility enhancement effects and drug adsorption properties of CNTs were investigated. CNTs were found to be a useful drug carrier system and they can provide a high loading and enhanced transdermal penetration for especially hydrophobic drugs. The electroconductive nature of CNTs allows easy application of iontophoresis and the additional advantage of CNTs appears to be using them as electrodes.