Nanoparticles can surmount some essential problems of conventional small molecules or biomacromolecules (e.g., DNA, RNA, and protein) used in some diseases by allowing targeted delivery and overcome through biological barriers. Recently, silver nanoparticles have been harnessed as delivery vehicles for therapeutic agents, including antisense oligonucleotides, and other small molecules. Silver is the most profit-oriented precious metal used in the preparation of nanoparticles and nanomaterials because of its antibacterial, antiviral, antifungal, antioxidant and unusually enhanced physicochemical properties compared to the bulk material such as optical, thermal, electrical, and catalytic properties. Small silver nanoparticles offer many advantages as drug carriers, including adjustable size and shape, enhanced stability of surface-bound nucleic acids, high-density surface ligand attachment, transmembrane delivery without harsh transfection agents, protection of the attached therapeutics from degradation, and potential for improved timed/controlled intracellular drug-delivery. Plant-mediated synthesis of silver nanoparticles is gaining interest due to its inexpensiveness, providing a healthier work environment, and protecting human health leading to lessening waste and safer products. The chapter presents the essential physicochemical characteristics, antibacterial, and anticancer properties which silver nanoparticles obtained by plant-mediated methods possess, and their application as drug-delivery systems with a critical view on the possible toxicity on the human body.

The precise characterization of lipid nanocarriers as drug delivery systems ensures guarantees for the quality of the product as an effective and safe form. The typical composition of SLN and NLC requires a comprehensive approach of characterization and in-depth analysis of the results to perform a drug delivery system with desired properties.

The multifunctional role of the human skin is well known. It acts as a sensory and immune organ that protects the human body from harmful environmental impacts such as chemical, mechanical, and physical threats, reduces UV radiation effects, prevents moisture loss, and helps thermoregulation. In this regard, skin disorders related to skin integrity require adequate treatment. Lipid nanoparticles (LN) are recognized as promising drug delivery systems (DDS) in treating skin disorders. Solid lipid nanoparticles (SLN) together with nanostructured lipid carriers (NLC) exhibit excellent tolerability as these are produced from physiological and biodegradable lipids. Moreover, LN applied to the skin can improve stability, drug targeting, occlusion, penetration enhancement, and increased skin hydration compared with other drug nanocarriers. Furthermore, the features of LN can be enhanced by inclusion in suitable bases such as creams, ointments, gels (i.e., hydrogel, emulgel, bigel), lotions, etc. This review focuses on recent developments in lipid nanoparticle systems and their application to treating skin diseases. We point out and consider the reasons for their creation, pay attention to their advantages and disadvantages, list the main production techniques for obtaining them, and examine the place assigned to them in solving the problems caused by skin disorders.

Resveratrol is a natural polyphenolic phytoalexin found in grapes, berry skins, roots of Japanese knotweed and is reputed as an excellent antioxidant, anti-inflammatory, neuro- and cardio- protective agent. Resveratrol has also beneficial effects in therapy of different skin conditions such as acne, exfoliative eczema, psoriasis and is known to provide a protection against ultraviolet radiation-mediated oxidative stress. However, its low oral bioavailability and short biological half- life compromise its beneficial therapeutic effects; therefore, its topical application is a practical approach in the treatment of various cutaneous disorders. Challenges associated with the development of topical resveratrol drug delivery systems and dosage forms include its low aqueous solubility as well as its poor UV-, pH- and temperature-dependent stability. The purpose of this article is to discuss the mechanism of action, therapeutic effect and physicochemical properties of resveratrol and to present recent technological approaches designed to improve its stability, bioavailability and therapeutic efficiency.

Phenolic compounds are a large, heterogeneous group of secondary metabolites found in various plants and herbal substances. From the perspective of dermatology, the most important benefits for human health are their pharmacological effects on oxidation processes, inflammation, vascular pathology, immune response, precancerous and oncological lesions or formations, and microbial growth. Because the nature of phenolic compounds is designed to fit the phytochemical needs of plants and not the biopharmaceutical requirements for a specific route of delivery (dermal or other), their utilization in cutaneous formulations sets challenges to drug development. These are encountered often due to insufficient water solubility, high molecular weight and low permeation and/or high reactivity (inherent for the set of representatives) and subsequent chemical/photochemical instability and ionizability. The inclusion of phenolic phytochemicals in lipid-based nanocarriers (such as nanoemulsions, liposomes and solid lipid nanoparticles) is so far recognized as a strategic physico-chemical approach to improve their in situ stability and introduction to the skin barriers, with a view to enhance bioavailability and therapeutic potency. This current review is focused on recent advances and achievements in this area.

The purpose of the study was to investigate the stability and biopharmaceutical characteristics of ketoprofen, loaded in polymeric carriers, which were included into a bigel in a semisolid dosage form. The polymer carriers with in situ-included ketoprofen were obtained by emulsifier-free emulsion polymerization of the monomers in aqueous medium or a solution of the polymers used. The morphological characteristics of the carriers, the in vitro release and the photochemical stability of ketoprofen were evaluated. The model with optimal characteristics was included in a bigel formulation. The bigel was characterized in terms of pH, rheological behavior, spreadability, and in vitro drug release. Acute skin toxicity, antinociceptive activity, anti-inflammatory activity, and antihyperalgesic effects of the prepared bigel with ketoprofen-loaded polymer carrier were evaluated. The carriers of ketoprofen were characterized by a high yield and drug loading. The particle size distribution varied widely according to the polymer used, and a sustained release was provided for up to 6 hours. The polymer mixture poly(vinyl acetate) and hydroxypropyl cellulose as a drug carrier, alone or included in the bigel composition, improved the photostability of the drug compared with unprotected ketoprofen. The bigel with ketoprofen-loaded particles provided sustained release of the drug and had optimal rheological parameters. In vivo experiments on the bigel showed no skin inflammation or irritation. Four hours after its application, a well-defined analgesic, anti-inflammatory, and antihyperalgesic effect was registered. The polymer mixture of poly(vinyl acetate) and hydroxypropyl cellulose as a carrier of ketoprofen and the bigel in which it was included provided an enhanced photostability and sustained drug release.

The aim of the study was to investigate the influence of the nature and composition of the monomer feed, added to the reaction system indomethacin/vinyl acetate/3-dimethyl (methacryloyloxyethyl) aminopropyl sulfonate (IMC/VAc/DMAPS) and the characteristics of the obtained polymer latexes on indomethacin In-situ loading, its kinetic release properties, and drug stability. Indomethacin loaded nanoparticles were obtained by an emulsifier-free emulsion radical copolymerization of the monomers, in presence of the drug. Transmission electron microscopy, Attenuated Total Reflection Fourier Transform Infrared spectroscopic analyses, Particle size distribution and zeta potential analysis were carried out to characterize the In-situ loaded nanocarriers. High-performance liquid chromatography and UV/VIS spectroscopic analyses were applied to determine the drug loading, In vitro release properties and stability studies of the drug used. High yield of 90 to 96% was obtained for the tested In-situ loaded nanocarriers. They possess a spherical shape with diameter ranging from 100 to 900 nm and zeta potential from -3.25 mV to -20.3 mV. Mono-modal and bi-modal particle size distribution was observed depending on monomer feed, added to the reaction system. It also influenced the drug loading and its release characteristics. Indomethacin was released from the investigated patterns following first order release. The nature and composition of the monomer feed, added to the reaction system IMC/VAc/DMAPS are an effective factors for the control of the indomethacin loading and also affect the rate and extent of drug-releasing but do not influence the kinetic model and drug transport mechanism. Stability studies indicated the stabilizing role of the polymer carrier on the In-situ included indomethacin.

Background: Solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) are useful drug delivery systems for dermal application. Thanks to their biocompatible and biodegradable profile, these carriers offer many advantages such as enhanced bioavailability, low toxicity, viable drug targeting and controlled release. SLN and NLC are composed of welltolerated lipids, including natural fats and oils that are successfully used in the pharmaceutical and cosmetic dermal formulation. Objective: This article presents an overview of the benefits of selecting natural fats and oils as structural components of SLN and NLC for topical application. Methods: This review is based on data published over the past 20 years about the development of stable and nontoxic lipid nanoparticles with natural lipids. We shed light on the role of natural fats in skin restoration, as well as on the contributed penetration and occlusive properties of SLN and NLC. Results: The deliberate selection of excipients (type and lipid ratio) influences the quality of the final dermal formulation. Natural lipids show good compatibility with different active molecules and are able to create stable lipid matrices that facilitate the biopharmaceutical properties of lipid nanoparticles. Patents involving natural fats and oils in SLN and NLC composition are listed, yet it is important to note that the approved marketed formulations are mainly cosmetic, not pharmaceutical, products. Conclusion: Natural lipids can enhance topical drug delivery by adding their ability of improving skin penetration and hydration to the permeation and occlusion properties of SLN and NLC.