Nanocarrier delivery

Torchilin, V. P. (2006). Multifunctional nanocarriers. Advanced Drug Delivery Reviews, Vol. 58, 14, (December 2006), pp. (1532-1555), ISSN 0169-409X Tran, V. T., Benoit, J. P. Venier-Julienne, M. C. (2011). Why and how to prepare biodegradable, monodispersed, polymeric microparticles in the field of pharmacy International Journal of Pharmaceutics, Vol. 407,1-2, (December 2011), pp. (1-11), ISSN 0378-5173... 

This final class of ELPs is used in nanocarriers and in dmg depots. In this section, the emphasis will be on systems that have already been tested in vivo, and on some recent promising developments in the area of ELP-assisted dmg delivery. 

Micellar nanocarriers have already been applied successfully for delivery of hydro-phobic drugs [86]. These carriers are usually the product of self-assembled block copolymers, consisting of a hydrophilic block and a hydrophobic block. Generally, an ELP with a transition temperature below body temperature is used as hydrophobic block and the hydrophilic block can be an ELP with a transition temperature above body temperature or another peptide or protein. The EPR effect also directs these types of carriers towards tumor tissue. 

Neu M, Germershaus O, Mao S, Voigt KH, Behe M, Kissel T (2007) Crosslinked nanocarriers based upon poly(ethylene imine) for systemic plasmid delivery in vitro characterization and in vivo studies in mice. J Control Release 118 370-380... 

Fig. 30 Types of nanocarriers for drug delivery, (a) Polymeric nanoparticles polymeric nanoparticles in which drugs are conjugated to or encapsulated in polymers, (b) Polymeric micelles amphiphilic block copolymers that form nanosized core-shell structures in aqueous solution. The hydrophobic core region serves as a reservoir for hydrophobic drugs, whereas hydrophilic shell region stabilizes the hydrophobic core and renders the polymer water-soluble.

The same group reported the simultaneous radiolabeling (with DOTA-anchored 4Cu) and fluorescence studies, coupled with biodistribution in vivo and in vitro (92). It is believed that appropriately functionalized SWNTs can efficiently reach tumor tissues in mice with no apparent toxicity (159). Furthermore, water-solubilised carbon nanotubes are nontoxic when taken up by cells even in high concentration (92). These studies have been complemented by the recent PET imaging of water-soluble 86Y labelled carbon nanotubes in vivo (mice) (160,161), to explore the potential usefulness of carbon nanocarriers as scaffolds for drug delivery. The tissue biodistribution and pharmacokinetics of model DOTA functionalized nanotubes have been explored in vivo (mouse model). MicroPET images indicated accumulation of activity mainly in the kidney, liver, spleen, and to a much less... 

An attractive strategy to improve CNS drug delivery is to link a nontransportable drug with a vector to the BBB. These moieties can work as molecular Trojan horses to transport across the BBB attached proteins, DNA molecules, and drug micro- and nanocarriers facilitating their penetration through the BBB. The choice of a vector moiety and a type of a linker is crucial for the success of this method of drug delivery. 

Research into the rational delivery and targeting of pharmaceutical, therapeutic, and diagnostic agents is at the forefront of projects in nanomedicine. These involve the identification of precise targets (cells and receptors) related to specific clinical conditions and choice of the appropriate nanocarriers to achieve the required responses while minimizing the side effects. Mononuclear phagocytes, dendritic cells, endothelial cells, and cancers (tumour cells, as well as tumour neovasculature) are key targets [280]. 

Sawant, R. M., Hurley, J. P., Salmaso, S., Kale, A., Tolcheva, E., Levchenko, T. S., and Torchilin, V. P. (2006), SMART drug delivery systems Double-targeted pH-responsive. Pharmaceutical nanocarriers, Bioconjugate Chem., 17, 943-949. 

Nishiyama, N., and Kataoka, K. (2006), Current state, achievements, and future prospects of polymeric micelles as nanocarriers for drug and gene delivery, Pharmacol. Therap., 112, 630-648. 

Various ocular delivery systems, such a ointments, suspensions, micro- and nanocarriers, and liposomes, have been investigated during the past two decades pursuing two main strategies to increase the corneal permeability and to prolong the contact time on the ocular surface [3],... 

List types of nanocarriers for drug delivery. Describe their stiiicture, principal differences, advantages and limitations. 

What size of polymer nanocarriers is the most appropriate for drug delivery ... 

Figure 47.1. Types of nanocarriers for drug delivery. A liposomes B nanoparticles C nanospheres D nanosuspensions E polymer micelles F nanogel G block ionomer complexes H nanofibers and nanombes.

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