Polymeric worm micelles as nano-carriers for drug delivery.
TL;DR: W worm micelles as blends of degradable polylactic acid and inert block copolymer amphiphiles were prepared for controlled release and initial study of carrier transport through nano-porous media, suggesting a new class of hydrophobic drug nano-carriers that are capable of tissue permeation as well as controlled release.
Abstract: Nanoscale carriers of active compounds, especially drugs, need not be spherical in shape. Worm micelles as blends of degradable polylactic acid (PLA) and inert block copolymer amphiphiles were prepared for controlled release and initial study of carrier transport through nano-porous media. The loading capacity of a typical hydrophobic drug, Triamterene, and the release of hydrophobic dyes were evaluated together with morphological changes of the micelles. Degradation of PLA by hydrolysis led to the self-shortening of worms and a clear transition towards spherical micelles, correlating with the release of hydrophobic dyes. Perhaps equally important for application is the flexibility of worm micelles, which we show allows them to penetrate nanoporous gels where 100 nm sized vesicles cannot enter. Such gels have served as tissue models, and so the results here collectively suggest a new class of hydrophobic drug nano-carriers that are capable of tissue permeation as well as controlled release.
Citations
More filters
Patent•
24 Jun 2009
TL;DR: In this paper, photodynamic therapy of vulnerable plaque using two pluralities of nanoparticles, one plurality comprising a PDT agent that is sensitive to blue green light wherein the nanoparticles are capable of penetrating only into the fibrous cap of the vulnerable plaque and another plurality comprising an agent sensitive to red light wherein they are able to penetrate into the core of the sensitive plaque.
Abstract: This invention relates to photodynamic therapy (PDT) of vulnerable plaque using two pluralities of nanoparticles, one plurality comprising a PDT agent that is sensitive to blue-green light wherein the nanoparticles are capable of penetrating only into the fibrous cap of the vulnerable plaque and one plurality comprising a PDT agent that is sensitive to red light wherein the nanoparticles are capable of penetrating into the core of the vulnerable plaque
24 citations
TL;DR: It was shown that the double-stabilized vesicles are readily internalized in HeLa and Caco-2 cells, and also non-covalently trapped in their respective interpenetrating acrylate networks.
Abstract: Vesicles from Pluronic L121 (PEO5-PPO68-PEO5) triblock copolymers were stabilized against aggregation by Pluronic P85 (PEO26-PPO40-PEO26) micelles. Both the vesicles and the micelles were reinforced by an interpenetrating polymer network from pentaerythritol tetraacrylate (PETA). AFM, electron microscopy and fluorescence labeling studies are used to investigate the morphology of the capsules. The P85 micelles are integrated into the L121 polymersome walls, while both types of Pluronic block copolymer are also non-covalently trapped in their respective interpenetrating acrylate networks. The micelle-containing vesicles retain their size upon heating until at least 33 °C. Upon cooling below room temperature the vesicles reversibly lose block copolymers. It was shown that the double-stabilized vesicles are readily internalized in HeLa and Caco-2 cells.
24 citations
TL;DR: In this paper, the improvement of the tribological properties of base oils through their composition modification by copper or molybdenum nanoparticles (nanopowder) is described, as well as results of an examination of wear amount of elements cooperating in friction couples lubricated with unmodified or modified oils.
Abstract: The present paper describes a part of an introductory examination concerning the improvement of tribological properties of base oils (used for lubricating as well as cutting oils compounding) through their composition modification by copper or molybdenum nanoparticles (nanopowder) addition. The results of tribological tests are presented as well as results of an examination of wear amount of elements cooperating in friction couples lubricated with unmodified or modified oils. These results testify to a positive influence of the described oil modification on its tribological properties manifested in friction couples.
23 citations
TL;DR: Poly(γ-benzyl-L-glutamate) (PBLG) has been selected for preparing non-spherical nanoparticles, which have a liquid crystal-like self organization of PBLG rods with varying lengths and are a valuable tool for gaining a better understanding of their fate in biological fluids, mechanisms of interactions with cells and in vivo distribution studies.
23 citations
TL;DR: In this article, small unilamellar vesicles are formed spontaneously by simple mixing of lamellae-forming diblock copolymer PB10PE10 (PB is a butylene oxide block, and PE an ethylene oxide layer) with micelle-forming Diblock CopolymerPB10PE18.
Abstract: Small unilamellar vesicles are formed spontaneously by simple mixing of lamellae-forming diblock copolymer PB10PE10 (PB is a butylene oxide block, and PE an ethylene oxide block) with micelle-forming diblock copolymer PB10PE18. Small angle neutron scattering (SANS) measurements show that the average vesicle radius may be as small as 30 nm with a polydispersity index of 0.15. From the SANS measurements it can also be deduced that the vesicles have a 3.4 nm thick hydrophobic membrane core and a 1.2 nm hydrophilic corona. Furthermore, it is seen that the vesicles coexist with spherical micelles. The influence of the mixing ratio as well as the concentration of the polymeric components is studied. Results of the micelle size, the vesicle size and the shell structure are confirmed by cryo-TEM measurements.
23 citations
References
More filters
TL;DR: The utility of polymeric micelles formed through the multimolecular assembly of block copolymers as novel core-shell typed colloidal carriers for drug and gene targeting and their feasibility as non-viral gene vectors is highlighted.
3,457 citations
TL;DR: This review examines the chemical nature of polymeric micelles as well as the methods used to characterize them with regard to drug delivery and potential medical applications, especially in cancer chemotherapy, are described and discussed.
1,200 citations
TL;DR: Experiments with poly(1,2-butadiene-b-ethylene oxide) diblock copolymers are described, which form Y-junctions and three-dimensional networks in water at weight fractions of PEO intermediate to those associated with vesicle and wormlike micelle morphologies.
Abstract: Amphiphilic compounds such as lipids and surfactants are fundamental building blocks of soft matter. We describe experiments with poly(1,2-butadiene-b-ethylene oxide) (PB-PEO) diblock copolymers, which form Y-junctions and three-dimensional networks in water at weight fractions of PEOintermediate to those associated with vesicle and wormlike micelle morphologies. Fragmentation of the network produces a nonergodic array of complex reticulated particles that have been imaged by cryogenic transmission electron microscopy. Data obtained with two sets of PB-PEOcompounds indicate that this type of self-assembly appears above a critical molecular weight. These block copolymers represent versatile amphiphiles, mimicking certain low molecular weight three-component (surfactant/water/oil) microemulsions, without addition of a separate hydrophobe.
1,126 citations
TL;DR: With all compositions, in both 100 nm and giant vesicles, the average release time reflects a highly quantized process in which any given vesicle is either intact and retains its encapsulant, or is porated and slowly disintegrates.
638 citations
TL;DR: A low molecular weight poly(ethyleneoxide)-poly(butadiene) (PEO-PB) diblock copolymer containing 50 weight percent PEO forms gigantic wormlike micelles at low concentrations (<5 percent by weight) in water.
Abstract: A low molecular weight poly(ethyleneoxide)-poly(butadiene) (PEO-PB) diblock copolymer containing 50 weight percent PEO forms gigantic wormlike micelles at low concentrations (<5 percent by weight) in water. Subsequent generation of free radicals with a conventional water-based redox reaction leads to chemical cross-linking of the PB cores without disruption of the cylindrical morphology, as evidenced by cryotransmission electron microscopy and small-angle neutron scattering experiments. These wormlike rubber micelles exhibit unusual viscoelastic properties in water.
626 citations