Nanoparticles lipid-based

Fig. 30. Schematic representation of lypophilic, radiolabeled complexes which have been encapsulated in lipid-based nanoparticles (150).

Solubility enhancement systems lipid-based systems, nanoparticles, surfactants, semisolid formulations... 

Liposome-polycation-DNA (LPD) nanoparticles (1) are formed by spontaneous rearrangement of a lipid shell around a polycation-condensed bacterial plasmid DNA core to form a virus-like structure (2). The LPD complexes consist of liposomes that are either made of cationic (LPDI) or anionic (LPDII) lipids and are sometimes referred to as lipopolyplexes, a broader category that also includes other lipid-based vectors (2). 

Jenning, V, Mader, K. and Gohla, S. H., Solid lipid nanoparticles (SLN) based on binary mixtures of liquid and solid lipids a H-NMR study. Int. J. Pharm., 205, 15-21, 2000. 

Scanning electron microscopy (SEM) seems to have been used only scarcely for the characterization of solid lipid-based nanoparticles [104], This method, however, is routinely applied for the morphological investigation of solid hpid microparticles (e.g., to smdy their shape and surface structure also with respect to alterations in contact with release media) [24,38,39,41,42,80,105]. For investigation, the microparticles are usually dried, and their surface has to be coated with a conductive layer, commonly by sputtering with gold. Unlike TEM, in SEM the specimen is scanned point by point with the electron beam, and secondary electrons that are emitted by the sample surface on irradiation with the electron beam are detected. In this way, a three-dimensional impression of the structures in the sample, or of their surface, respectively, is obtained. 

Alternatively, nanosized drug delivery particles, such as lipid-based nanoparticles or the nano-structured lipid dispersions can be produced by dispersing water-insoluble drug in lipid-based... 

Hattori, Y., Sakaguchi, M., and Maitani, Y. (2006), Folate-linked lipid-based nanoparticles deliver a NFkappaB decoy into activated murine macrophage-like RAW264.7 cells, Biol. Pharm. Bull, 29(7), 1516-1520. 

Mulder WJ, Strijkers GJ, van Tilborg GA, Griffioen AW, Nico-lay K. Lipid-based nanoparticles for contrast-enhanced MRI and molecular imaging. NMR Biomed. 2006 19 142-164. 

A novel nanoparticulate lipid-based carrier system was developed by Mumper et al. at the University of Kentucky. ° This carrier system is composed of a lipophilic-emulsifying wax such as cetyl alcohol/ polysorbate 60 and other surfactants such as Brij 72, Brij 78, and Tween 80. The nanoparticles were formed through a warm microemulsion technique where encapsulates have included paclitaxel and plasmid DNA. The emulsification process is spontaneous, and cooling of the emulsion causes solidification of the nanoparticle-containing drug. This novel carrier has shown high efficiency in drug delivery across the blood-brain barrier. 

Bummer PM. Physical Chemical Considerations of Lipid-Based Oral Drug DeliverynSolid Lipid Nanoparticles. Crit Reviews in Ther Drug Carrier Sys 2004 21 1-19. 

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. 

Formulation strategies toward poorly soluble and poorly dispersible drugs focus on obtaining as highly dispersed a drug as possible. Such dispersions usually involve stabilization with surface active molecules. Possible dosage forms include lipid-based formulations, nanoparticle preparations, and solid dispersions [7,8,20,21]. 

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