Nanocarriers for Drug Delivery

Monoclonal andbody directed insulin or Tf receptors were also udhzed to target PEGylated immunoliposomes for d ansvascular 

The mechanism by w hich immunoUposomes penetrate across the BBB is not fully understood. It w as hypothesized that the process involves the binding of immunoliposomes to multiple capillary luminal membrane receptors, fusion of the liposomes with several vesicular pits into a large vesicle and transcytosis of this vesicle to the abluminal membrane border (Comford and Comford, 2002). Studies by electron microscopy support this hypothesis (Faustmann andDermietzel, 1985). 

Carbon nanotubes and nanofibers have lately attracted great attention in nanomedicine including their potential use as drug carriers, although there are also considerable concerns associated with their safety (Lange et al., 2003 Muller et al., 

In the future, nanotubes and nanofibers can be administered systemically, if the problem of their toxicity is addressed, for example, by appropriate polymer coating. In this respect, the continuous nanofibers are more likely to be used in implants or tissue engineering applications. 

A distinct case of the vehicle-mediated CNS drug delivery employs specific cells carriers that can incorporate micro- and 

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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.

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

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.

Dufresne MH, Le Garrec D, Sant V, et al. Preparation and characterization of water-soluble pH-sensitive nanocarriers for drug delivery. Int J Pharm 2004 277 81-90. 

Mura S, Nicolas J, Couvreur P (2013) Stimuli-resptmsive nanocarriers for drug delivery. Nat Mater 12 991... 

J. Nicholas, S. Mura, D. Brambilla, N. Mackiewicz, P. Coreur, Design functionalization strategies and biomedical applications of targeted biodegradable. Biocompatible polymer based nanocarriers for drug delivery, Chem. Soc. Rev. 42 (2013) 1147-1235. 

Cheng Z, Thorek DLJ, Tsourkas A. Porous polymersomes with encapsulated Gd-labeled den-drimers as highly efficient MRI contrast agents. Adv Funct Mater 2009 19 3753-9. Kesharwani P, Jain K, Jain NK. Dendrimer as nanocarrier for drug delivery. Prog Polym Sci 2014 39 268-307. 

Kesharwani P, Jain K, Jain NK. Dendrimer as nanocarrier for drug delivery. Prog Polym Sci 2014 39 268-307. 

Kim Y, Dalhaimer P, Christian DA, Discher DE (2005) Polymeric worm micelles as nanocarriers for drug delivery. Nanotechnology 16 S484... 

Another pH-sensitive linker used for the preparation of smart nanocarriers for drug delivery is the cis-aconitic spacer. Choi et al. (1999) conjugated DOX to HPMA through this spacer and observed increased release in acidic pH, resulting in significant cytotoxicity upon incubation with human ovarian carcinoma cells. 

Chen, C.-Y.,Kim,T.H.,Wu,W.-C. [2013], pH-dependent,thermosensitive polymeric nanocarriers for drug delivery to soiid tumors. Biomaterials, 34,4501-4509. 

Dhanikula, R.S., EHldgen, P, 2006. Synthesis and evaluation of novel dendrimers with a hydrophilic interior as nanocarriers for drug delivery. Bioconjug. Chem. 17 (1), 29-41. 

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