Nanoparticle drug carrier systems

Fraunhofer, W., G. Winter and C. Coester (2004). Asymmetrical flow field-flow fractionation and multiangle light scattering for analysis of gelatin nanoparticle drug carrier systems. Anal Chem 76(7) 1909-20. 

J., Dougherty, T.J. and Prasad, P.N. (2003) Ceramic-based nanoparticles entrapping water-insoluble photosensitizing anticancer drugs A novel drug-carrier system for photodynamic therapy. Journal of the American Chemical Society, 125, 7860-7865. 

Recently, many studies have focused on self-assembled biodegradable nanoparticles for biomedical and pharmaceutical applications. Nanoparticles fabricated by the self-assembly of amphiphilic block copolymers or hydrophobically modified polymers have been explored as drug carrier systems. In general, these amphiphilic copolymers consisting of hydrophilic and hydrophobic segments are capable of forming polymeric structures in aqueous solutions via hydrophobic interactions. These self-assembled nanoparticles are composed of an inner core of hydrophobic moieties and an outer shell of hydrophilic groups [35, 36]. 

Muller, R. H., et al., Sohd lipid nanoparticles (SLN) an alternative colloidal drug carrier system for controlled drug debvery. Eur. J. Pharm. Biopharm., 41, 1995. 

Uner M. (2006). Preparation, characterization and physico-chemical properties of solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) their benefits as colloidal drug carrier systems. Pharmazie, 61, 375-386. 

Use of drug carrier systems such as nanoparticles, microspheres, liposomes, etc., which would remain in the cul-de-sac for a long period of time, thus giving a sustained action. 

Balthasar, S., K. Michaelis, et al. (2005). Preparation and characterisation of antibody modified gelatin nanoparticles as drug carrier system for uptake in lymphocytes. Biomaterials 26(15) 2723-32. 

Vauthier, C. Couvreur, P. Development of polysaccharide nanoparticles as novel drug carrier systems. In Handbook of Pharmaceutical Controlled Release Technology Wise, Trantolo, Cichon, Inyang, Stottmeister, Eds. Marcel Dekker, Inc. New York, 2000 413 29, Chap. 21. 

Besides liposomes, polymeric nanoparticles may be used as effective drug carrier systems using cytotic pathways. Particle size and polymeric composition help control particle degradation and drug release. Recently, it was shown in a rat study that polybutylcyanoacrylate nanoparticles, which had been surface coated with polysorbate 80, exhibited a 20-fold higher uptake into brain capillary endothelial cells compared to noncoated nanoparticles [17]. It is assumed that association of lipoproteins at the surface triggers the endocytotic uptake of the nanoparticles. 

Vauthier C, Couvreur P (2000). Development of Polysaccharide Nanoparticles as Novel Drug Carrier Systems. In D L Wise (ed.). Handbook of Pharmaceutical Controlled Release Technology. Marcel Dekker, New York, pp. 413-429. 

Aumelas, A. Serrero, A. Durand, A. Dellacherie, E. Leonard, M. Nanoparticles of hydrophobically modified dextrans as potential drug carrier systems. Colloids Surf. B 2007, 59 (1), 74-80. 

FIGURE 30.5 Nano- and microparticulate drug carrier systems, (a) Microsphere, (b) microcapsule, (c) surface modified nanoparticles, (d) nanosphere, (e) nanocapsule, and (f) surface modified targeting molecules conjugated nanoparticles. 

Bummer PM. Physical chemical considerations of lipid-based oral drug delivery—Solid lipid nanoparticles. Critical Reviews in Therapeutic Drug Carrier Systems. 2004 21(1) 10-20. 

Incubation of nanoparticles with cells in media leads to adsorption of serum proteins on their surface that increases the entry of nanoparticles into the cells by receptor-mediated endocytosis. However, during in vivo applications, designed nanoparticles can facilitate clearance by the reticuloendothelial system (mononuclear phagocyte system) because of serum proteins on the nanoparticle surface. Macrophages located in the liver and spleen remove nanoparticles bound with serum proteins (fibronectin, laminin, etc.). Binding of plasma protein is the first step for RES to remove the circulating nanosized drug carrier systems within a few hours. 

Nanoparticles are colloidal and submicron particles generally having 10-500 nm particle size and prepared from different polymers for drug carrier systems. Drug molecules are encapsulated in nanoparticles by several methods or adsorbed on the surface of nanoparticles by electrostatic interactions. " ... 

It is possible to prepare various kinds of nanoparticles with different surface charges and particle sizes depending on the polymer composition and preparation technique. As a result, the particle size of nanoparticles varies from 10 nm to 200 nm and the surface charge - -5 mV to -1-50 mV. In this manner, drug carrier systems can be formed through different routes such as oral, parenteral and other mucosal routes for local or systemic therapy, with high cellular interaction, loading capacity, transfection efficiency and low toxicity. 

Solid lipid nanoparticles were originally developed for parenteral drug delivery to provide a parenteral drug carrier system based on physiological compounds and a potential controlled release and/or targeting of the drug. A broad variety of drugs (e.g. doxorubicin, camptothecin, etoposide, mitoxan-trone, tamoxifen,paclitaxel, clozapine, lovastatin, bromocriptine, temozolomide, actarit and dexametha-sone °) has already been incorporated into SLN formulations and tested in vivo in mice or rat. 

Cholesteryl myristate nanoparticles are excellent model systems to study the phase behavior and influencing parameters like particle size and stabilizer system, but are not applicable as robust drug carrier system due to their relatively high crystallization temperature (above or around 0°C). As storage at 4°C appears advantageous with respect to the chemical stability of the dispersions a robust formulation should allow long-term storage at this temperature without nanoparticle crystallization. 

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