Angeliki Siamidi

By Marilena Vlachou and Angeliki Siamidi

Melatonin (N-acetyl-5-methoxytryptamine, MLT), a hormone synthesized by the pineal gland and released at night, has a regulatory role on sleep in vertebrates, including humans. It has been shown to have a hypnotic action in animals and humans and it has been used as an agent for restoring circadian rhythms, disturbed by jet-lag, shift-work or aging. The physiological actions of melatonin in regulating seasonal and circadian rhythms are mediated through a family of specific, high affinity G protein-coupled membrane receptors. The beneficial effect of fast-release formulations on sleep initiation may come from the high amount of melatonin released immediately after administration, while the benefit of the sustained release systems comes from the release of melatonin in small dosages during the entire night period. This chapter covers the recent scientific work on melatonin modified release formulations.

Part of the book: Melatonin

By Marilena Vlachou, Angeliki Siamidi and Sotiria Kyriakou

A detailed account of the construction, properties, and practical applications of electrospinning for the fabrication of high-quality ultrafine fibers, suitable for drug delivery, is given. With respect to the electrospinning method, various parameters are of crucial importance. The electrospinning parameters are classified as solution properties, process parameters, and environmental conditions. The solution properties include the polymer concentration, molecular weight and viscosity, the solution conductivity and relative volatility, volatility of the solvent, surface tension, and dielectric constant. The process parameters refer to the flow rate, the applied voltage, the needle diameter, and the distance between the tip of the needle and collector and the geometry of the collector. The environmental conditions include the relative humidity and temperature. All these factors are responsible for a flawless electrospinning process, which leads to the formation of the desirable electrospun nanofibers with the requisite characteristics. In this chapter, it has been shown that the electrospinning technology could provide a useful method for modifying drug release behavior and opens new routes for the development of effective and tailor-made drug release carriers.

Part of the book: Electrospinning and Electrospraying

By Angeliki Siamidi, Eleni Tsintavi, Dimitrios M. Rekkas and Marilena Vlachou

The broad spectrum of applications of three-dimensional printing (3D printing, 3DP) has attracted the attention of researchers working in diverse fields. In pharmaceutics, the main idea behind 3D printing products is to design and develop delivery systems that are suited to an individual’s needs. In this way, the size, appearance, shape, and rate of delivery of a wide array of medicines could be easily adjusted. The aim of this chapter is to provide a compilation of the 3D printing techniques, used for the fabrication of oral drug delivery systems, and review the relevant scientific developments in particular those with modified-release characteristics.

Part of the book: Molecular Pharmacology

By Angeliki Siamidi and Yannis Dotsikas

The pineal hormone melatonin (MLT) is a derivative of the amino acid L-tryptophan and controls the circadian diurnal rhythm and the seasonal biorhythm. Exogenous administration is aimed at alleviating sleep-related dysfunctions and jet lag, as it decreases sleep-onset latency, increases total sleep time and improves overall sleep quality. Besides these indications, MLT has been shown to have other actions, such as antioxidant, immune enhancement and anticancer. It has also been shown to be useful against cardiovascular, neurological and psychiatric diseases. In the context of this work, a review of the related literature on the modified release of MLT from its per os administered formulations is presented, including the utilization of the design of experiments (DoE) for the selection of the optimal composition of melatonin formulations. The chapter offers an account of the recent advantages on MLT’s solid dosage forms suitable for treating sleep disorders, referring either to its onset or maintenance.

Part of the book: Melatonin