ABSTRACT
A recent focus of nanotechnology in medicine has been on drug delivery systems (DDS) using therapeutic colloidal nanocarriers, including polymeric nanoparticles (NPs), liposomes, and micelles. Polymeric NPs have some distinct advantages over liposomes. For example, it is possible for the drug release pro›le of polymeric NPs
18.1 Background ................................................................................................... 355 18.2 Production and Use of Nanoparticles ........................................................... 356
18.2.1 Preparation of Nanoparticles ............................................................ 356 18.2.2 Biodistribution of Nanoparticles in EAU Rats ................................. 357 18.2.3 Drug Treatment ................................................................................. 357 18.2.4 Histopathology .................................................................................. 357
18.3 Results Using Nanoparticles ......................................................................... 358 18.3.1 Biodistribution of Nanoparticles in EAU Rats ................................. 358 18.3.2 Therapeutic Effects of Stealth Nanosteroids .................................... 358 18.3.3 Histopathology .................................................................................. 359
18.4 Summary and Future Challenges .................................................................360 References .............................................................................................................. 361
to be modulated, and these NPs are more stable in biological •uids. Among the polymeric NPs for controlled drug delivery, biodegradable and biocompatible poly (d, l-lactic acid)/poly (d, l-lactic/glycolic acid)/(PLA/PLGA)-based NPs have been investigated as carriers for therapeutic bioactive molecules. PLA/PLGA has been studied for many years and is approved by the U.S. Food and Drug Administration for human therapy. Also, poly(ethylene glycol) (PEG) is used for surface modi›cation of NPs to reduce opsonization and prevent interactions with the mononuclear phagocyte system (MPS) (Bazile et al. 1995). The main advantages of PEG NPs (stealth NPs) compared to other long-circulating systems are their shell stability and their ability to control the release of the encapsulated compound. In this regard, PEG-PLA/PLGA helps to stabilize the inner core, reduce droplet size, and encapsulate drugs. Thus, stealth NPs could markedly improve the pharmacological properties of drugs.
