Long circulating polymeric nanoparticles for gene/drug delivery

• Published in: Current drug metabolism
• Main Authors: Hu, Jiaming, Sheng, Yan, Shi, Junfeng, Yu, Bohao, Yu, Zhiqiang, Liao, Guochao
• Format: Journal Article
• Language: English
• Published: Netherlands 01.01.2018
• Subjects: Long circulation; Polymeric nanoparticles; Gene/drug delivery; Opsonization; Biodistribution; Mononuclear phagocyte system
• ISSN: 1875-5453
• DOI: 10.2174/1389200219666171207120643

The major limitation in the improving polymeric nanoparticles into an efficient gene/drug delivery carrier is the rapid opsonization, phagocytic uptake by mononuclear phagocyte system and subsequent clearance from the bloodstream. The prolonged circulation time of nanoparticles in the blood is a prerequisite to realizing a controlled and targeted (passive or active targeting) release of the encapsulated gene/drug at the desired site of action. In this review, the factors such as biological barriers and physical barriers including particle size, shape, zeta potential, and hydrophilicity will be discussed, which can cause effects on blood clearance and organ accumulation. Some natural and synthetic polymers utilized in long-circulating nanoparticles will also be discussed. The most popular method to mask or camouflage nanoparticles is the adsorbed, grafted or conjugated of poly (ethylene glycol) (PEG) or other hydrophilic polymers (e.g. polysaccharides) to the particle surface. Surface modification of nanoparticles with these polymers results in an increased blood circulation time by several orders of magnitude in comparison to the bare nanoparticles. However, the circulation half-life of nanoparticles still cannot satisfy the need for clinical use. At present, identification of novel potential coating materials is an emerging field of interest in the design of long-circulating polymer-based nanoparticulate gene/drug delivery.