Polylactide nanoparticles

Pfister A, Zhang G, Zareno J, Horwitz AF, Fraser CL (2008) Boron polylactide nanoparticles exhibiting fluorescence and phosphorescence in aqueous medium. ACS Nano 2 1252-1258... 

Bourges JL, Gautier SE, Delie F, et al. Ocular drug delivery targeting the retina and retinal pigment epithelium using polylactide nanoparticles. Invest Ophthalmol Vis Sci 2003 44 3562-3569. 

Urban M, Musyanovych A, Landfester K (2009) Fluorescent superparamagnetic polylactide nanoparticles by combination of miniemulsion and emulsion/solvent evaporation techniques. Macromol Chem Phys 210 961-970... 

Legrand P, Lesieur S, Bochot A et al (2007) Influence of polymer behaviour in organic solution on the production of polylactide nanoparticles by nanoprecipitation. Int J Pharm... 

The hydrophobic core of nanoparticles is mostly made of solid glassy polymers such as polycaprolactone, polylactide, and their random copolymers. Drags are physically trapped and dispersed in the core. Except for the initial burst release period, the drug release from the solid nanoparticle cores tends to be a slow diffusion-controlled process [126]. Thus, nanoparticles responding to the acidic environments of tumor intercellular fluid or intracellular acidic compartments have been developed for fast drug release. 

The above mentioned scaffolds were made completely of the ceramic materials. Other potential materials which could be used to fabricate a novel construct for the repair of ciitical-sized bone defects is a novel material made of biodegradable polymer reinforced with ceramics particles. The properties of such a composite depend on 1) properties of the polymer used for the matrix and properties of the ceramics used for the reinforcement, 2) composition of the composite (i.e. content of ceramic particles) and 3) size, shape and arrangement of the particles in the matrix. Several polymer-composite composites have been used for scaffolds fabrication including polylactide (PLA) and polycaprolacton (PCL) reinforced with calcium phosphate (CaP) micro and nanoparticles. Authors proposed a novel composite material by blending copolymer -Poly(L-lactide-co-D,E-lactide) (PLDLLA) a copolymer with a ceramic - Tri-Calcium Phosphate... 

Muller, R.H. et al.. Cytotoxicity of magnetite-loaded polylactide, polylactide/gly-colide particles and solid lipid nanoparticles, Int. J. Pharm., 138, 85, 1996. 

In addition to the above-mentioned experiments using PS-based nanoparticles, the hydrophobic fluorescent dye A-(2,6-diisopropylphenyl)perylene-3,4-dicarbonacidimide (PMI) could also be successfully incorporated in phosphate-functionalized poly(methylmethacrylate) (PMMA) and PS [33], polyisoprene (PI), PS-co-PI [34], PBCA [35, 36] and polylactide (PLLA), or poly(e-caprolactone) (PCL) nanoparticles [37] in order to study the cellular response to these polymeric nanoparticles. For qualitative investigations, confocal microscopy can be used the quantitative measurements can be realized by a fluorescent activated cell sorter (FACS). 

Bourges et al. studied the kinetics of polylactide (PLA) nanoparticle (NP) localization within the intraocular tissues and to evaluate their potential to release encapsulated material. Environmental scanning electron microscopy (ESEM) showed the flow of the NPs from the site of injection into the vitreous cavity and their rapid settling on the internal limiting membrane. Histology demonstrated the anatomic integrity of the injected eyes and showed no toxic effects. A mild inflammatory cell infiltrate was observed in the ciliary body 6 h after the injection and in the posterior vitreous and retina at 18-24 h. The intensity of inflammation decreased markedly by 48 h. Confocal and fluorescence microscopy and immunohistochemistry showed that a transretinal movement of the NPs was... 

R. Dinarvand, N. Sepehri, S. Manoochehri, H. Rouhani, F. Atyabi, Polylactide-co-glycolide nanoparticles for controlled delivay of anticancer agents, Int. J. Nanomedicine 6 (2011) 877-895. 

Shi, G., M. Rouabhia, Z. Wang, L.H. Dao, and Z. Zhang. 2004. A novel electrically conductive and biodegradable composite made of polypyrrole nanoparticles and polylactides. Biomateriak... 

The conductive and biodegradable nano composite was made of PPy and polylactide [264,265]. PPy nanoparticles were incorporated into the poly-lactide matrix via the emulsion polymerization of pyrrole in the aqueous... 

Montmorillonite (MMT), a smectite clay, is probably the most extensively studied nanomaterial in terms of mechanical, thermal, fire retardant or crystallization behavior of polylactide, especially when these nanoparticles are organically modified allowing the achievement of intercalated and exfoliated nanocomposites.These nanocomposites show enhanced properties as compared to microcomposites and pristine polymer. However, biodegradation and hydrolytic degradation of PLA in the presence of nanoclays has been investigated to a small extent. 

Endocytosis is essential for uptake of macromolecules and nanoparticles. Thereby, the physical and chemical characteristics of the cargo and transporter complex determine the nature of the cell uptake mechanism. Particles larger than 500 nm are typically phagocytosed or macropinocytosed, whereas smaller hydrophilic molecules are internalized by any of the various endocytotic processes [2,8]. Often, nanometersized transporter molecules or particles accomplish cell uptake simultaneously by several endocytotic mechanisms [9]. Clathrin-dependent endocytosis is the most widely understood pathway, which is present in nearly aU mammalian cells. The clathrin pathway is considered the most important uptake mechanism for several polymers such as poly(ethylene glycol)-polylactides, poly(lactide-c )-glycolide) (PLGA), silica-based nanoparticles, and chitosan nanoparticles [8, 10-12]. 

In order to facilitate uniform dispersion of the inorganic nanoparticles in polymer nanofibers, a surfactant is sometimes used. The nontoxic and cell-friendly surfactant 12-hydroxystearic acid (HSA) was used to incorporate the hydrophilic ceramic powder hydroxyapatite (HA), which presents low affinity for organic solvents and hydrophobic polymers, into polylactide (PLA) [5]. The surfactant stabilizes the dispersion that otherwise would settle within a few minutes. Other surfactants typically used are the anionic AOT [6-8] or the nonionic Triton-X-100 [9]. 

Dawson GF, Halbert GW (2000) The in vitro cell association of invasin coated polylactide-co-glycolide nanoparticles. Pharm Res 17 1420-1425... 

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