ABSTRACT
Nanotechnology is the science that deals with particles or constructs which have
dimensions ranging from several nanometers to around 100 to 150 nm (Fig. 1), although
more commonly the upper limit is stretched to 200 nm. It is not possible to cover the whole
gamut of nanotechnology or even only the pharmaceutical aspects of the subject in all its
manifestations in one chapter. As a discipline, nanotechnology has already spawned
several journals dealing with the physics, biology, toxicology, engineering, and pharma-
ceutical applications; many books (1-4); chapters and reviews; and a rapidly growing
number of scientific papers and consensus reports (5,6). However, a treatise on modern
pharmaceutics could hardly ignore the subject of pharmaceutical nanotechnology, which
shows such promise, even though the field may be tainted somewhat with the hype from
which it suffers (7). Elsewhere in the book, other chapters consider the topic: chapter 1,
volume 1 suggests that many aspects of nanotechnology will feature in future paradigms of
pharmaceutical research and has discussed some of the unsolved issues; chapter 9, volume
2 addresses target-oriented drug delivery including nanoparticulate carrier systems; and
chapter 13, volume 1 on disperse systems draws attention to nanosuspensions. The thrust of
this chapter is the use of nanoparticles as drug carriers and targeting agents, and it also
points to the potential use of nanoparticles as excipients and as part of new, often hybrid
materials. Its emphasis is on the pharmaceutics of these nanosystems. The chapter does not
address liposome technology or solid lipid nanoparticle (SLN) systems. Liposomes are
exhaustively covered in the three volumes edited by Gregoriadis and published in 2006 (8).
SLNs have a large literature and are the subject of a recent review (9).
