Nanoparticle (NP) drug delivery systems (5−250 nm) have the potential to improve current disease therapies because of their ability to overcome multiple biological barriers and releasing a therapeutic load in the optimal dosage range. Rapid clearance of circulating nanoparticles during systemic delivery is a critical issue for these systems and has made it necessary to understand the factors affecting particle biodistribution and blood circulation half-life. In this review, we discuss the factors which can influence nanoparticle blood residence time and organ specific accumulation. These factors include interactions with biological barriers and tunable nanoparticle parameters, such as composition, size, core properties, surface modifications (pegylation and surface charge), and finally, targeting ligand functionalization. All these factors have been shown to substantially affect the biodistribution and blood circulation half-life of circulating nanoparticles by reducing the level of nonspecific uptake, de...

http://pubs.acs.org/doi/pdf/10.1021/mp800051m

Factors Affecting the Clearance and Biodistribution of Polymeric Nanoparticles

Nanotechnology is the understanding and control of matter generally in the 1-100 nm dimension range. The application of nanotechnology to medicine, known as nanomedicine, concerns the use of precisely engineered materials at this length scale to develop novel therapeutic and diagnostic modalities. Nanomaterials have unique physicochemical properties, such as ultra small size, large surface area to mass ratio, and high reactivity, which are different from bulk materials of the same composition. These properties can be used to overcome some of the limitations found in traditional therapeutic and diagnostic agents.

Nanoparticles in Medicine: Therapeutic Applications and Developments

Sasidharan Swarnalatha Lucky,†,§ Khee Chee Soo,‡ and Yong Zhang*,†,§,∥ †NUS Graduate School for Integrative Sciences & Engineering (NGS), National University of Singapore, Singapore, Singapore 117456 ‡Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore 169610 Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore, Singapore 117576 College of Chemistry and Life Sciences, Zhejiang Normal University, Zhejiang, P. R. China 321004

Nanoparticles in photodynamic therapy.

Tissue engineering applications commonly encompass the use of three-dimensional (3D) scaffolds to provide a suitable microenvironment for the incorporation of cells or growth factors to regenerate ...

/pdf/three-dimensional-scaffolds-for-tissue-engineering-1huqh8s1ln.pdf

Three-dimensional scaffolds for tissue engineering applications : role of porosity and pore size

Nanotechnology, or systems/device manufacture at the molecular level, is a multidisciplinary scientific field undergoing explosive development. The genesis of nanotechnology can be traced to the pr...

Nanotechnology and medicine.

The pinpoint promise of nanoparticle-based drug delivery and molecular diagnosis

Nanotechnology, or systems/device manufacture at sizes generally ranging between 1 and 100 nm, is a multidisciplinary scientific field undergoing explosive development. The genesis of nanotechnology can be traced to advances in medicine, communications, genomics and robotics. One of the greatest values of nanotechnology will be in the development of new and effective medical treatments (i.e. nanomedicine). This review focuses on the potential of nanomedicine as it relates to the development of nanoparticles for enabling and improving the targeted delivery of therapeutic and diagnostic agents. We highlight the use of nanoparticles for specific intra-compartmental analysis using the examples of delivery to malignant cancers, to the central nervous system, and across the gastrointestinal barriers.

Targeted nanoparticle-based drug delivery and diagnosis

Extensive neuroprotection by choroid plexus transplants in excitotoxin lesioned monkeys.

The objective of this study was to evaluate the in vivo secretion profile of ciliary neurotrophic factor (CNTF) from either of two genetically engineered cell lines contained in the encapsulated cell therapy (ECT)-based NT-501 device. ECT devices were loaded with either a low or high CNTF-secreting cell line and implanted into rabbit eyes for 1, 3, 7, 14, 30, 60, 90, 135, 180, or 365 days. After explantation, the vitreous was sampled and devices were allowed to incubate in endothelial serum-free medium for 24 h at 37 degrees C. Both the vitreous and the conditioned medium were assayed for CNTF using an ELISA. Device and vitreous CNTF, were plotted against time, and regression analysis was used to calculate half-life. Devices loaded with either cell line showed stable in vivo output for the duration of the study, with populations of healthy cells remaining in the device at study termination. For the low-dose CNTF-secreting cell line, with the final time point at 6 months, the halflife was estimated as 71 days, whereas the high-dose devices, with a final time point of 1 year, had an associated half-life of approximately 198 days. The NT-501 device is capable of delivering CNTF to the vitreous for at least 1 year. This ECT-based device, which has been shown to be safe and effective by our group, is a well-engineered ECT-based controlled delivery system capable of protein output on the order of years.

Christopher G. Thanos

Papers

Nanotechnology and medicine.

The pinpoint promise of nanoparticle-based drug delivery and molecular diagnosis

Targeted nanoparticle-based drug delivery and diagnosis

Extensive neuroprotection by choroid plexus transplants in excitotoxin lesioned monkeys.

Sustained Secretion of Ciliary Neurotrophic Factor to the Vitreous, Using the Encapsulated Cell Therapy-Based NT-501 Intraocular Device