1 - Principles of nanosized drug delivery systems

Abstract

The selection of nanosized drug delivery systems is very wide, containing pure solid drug nanoparticles and very sophisticated and complex engineered nanomachines. The research in the field of drug nanocarriers is very intensive and all the time increasing in volume, but still the number of products entering the market is quite low and concentrated mainly only to a few types of nanosystems. Very descriptive to all the nanoresearch is the example of injectable drug nanocarriers during the last 10 years: in all of those studies, only around 1% of the total injected drug dose did reach the desired site of action. This emphasizes the importance of understanding the properties of biological membranes, their impact on permeation, and, most importantly, the need for thorough understanding of the physicochemical properties and the related interactions of the drug nanocarriers with the biological membranes. In this chapter, first the determinations of nanosized drug delivery systems and their most important properties/characteristics are presented. Then, different types of nanosystems/nanovehicles are discussed, followed by cell and barrier interactions and particle properties important to these interactions. Finally, utilization of nanosized materials in medical applications, including diagnostic and theranostic applications, is shortly described.