Furosemide, a chloride channel blocker ordinarily used as a high-ceiling or loop diuretic, is practically insoluble in water and dilute acids. Due to its acidic nature, furosemide is mostly absorbed in the stomach and in the upper small intestine. Efforts have focused on the development of sustained release systems of furosemide in order to improve the effectiveness of the drug, which exhibits poor aqueous solubility and poor permeability. Recently, electrospun nanofibrous drug delivery systems have emerged as promising alternative solid-dosage forms due to their advantages of high porosity, high surface to volume ratio, and high drug-loading efficacy. Herein, a number of nanofibrous mats composed of different types of Eudragit® polymers in various concentrations and combinations loaded with furosemide were designed, successfully electrospun, and characterized using SEM, FTIR, DSC, and TGA analyses. The nanofibrous nonwovens were formulated in nanofiber tablets and the release profile of furosemide from them was evaluated at pH 1.2 and 6.8 and compared to that of physical mixture matrix tablets of analogous composition as well as to that of a commercial formulation. It was found that the release of furosemide was compatible with the gastroretentive and slower intestinal release requirements with a well-defined absorption window, while some nanofiber formulations could act as furosemide carriers in emergency situations where a relatively fast onset of its action is required, as in the case of critically ill post-traumatic patients.

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 tailormade drug release carriers.