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
TL;DR: The ability to vary the network properties by blending filomicelles with spherical micelles is demonstrated and the deposition of a dense polymer coating on the mucin network was shown to act as a barrier to control diffusion and improved the structural stability under simulated oral chemical conditions.
Abstract: Mucin networks are lubricous biofunctional coats formed through the continuous deposition of mucin glycoproteins. Previously, we demonstrated the synthesis of a mucin mimic using biotinylated-filomicelles crosslinked via streptavidin using a layer-by-layer approach. These networks recreate the fibrous nature of mucin and can serve as a drug-releasing network. In this work, the ability to vary the network properties by blending filomicelles with spherical micelles is demonstrated. In addition, the deposition of a dense polymer coating on the mucin network was shown to act as a barrier to control diffusion and improved the structural stability under simulated oral chemical conditions. These biomimetic coatings can be utilized as a delivery system, providing a tunable drug release for oral applications.
7 citations
TL;DR: This work will examine key advances in the areas of diagnostics and synthetic biology that have led to visionary contributions to next-generation medicine and present 2 devices that will contribute to the realization of compelling biosensing and biofunctional material technologies.
7 citations
TL;DR: In this paper, the self-organization of linear diblock copolymers poly(ethylene oxide)polylactide and triblock copylactide in aqueous solution is studied by the dissipative particle dynamics method, and quantitative comparison with the experimental data is performed.
Abstract: The self-organization of molecules of linear diblock copolymer poly(ethylene oxide)–polylactide and triblock copolymer polylactide–poly(ethylene oxide)–polylactide in aqueous solution is studied by the dissipative particle dynamics method, and quantitative comparison with the experimental data is performed. It is shown that the diblock copolymers are aggregated to spherical micelles, their average aggregation number increases with increasing both polymer concentration and hydrophobic block length. For the given type of molecules, the simulation results agree well with the experiment. For the case of triblock copolymers it is predicted that stable supramolecular aggregates of various morphologies exist in solution even at low concentrations.
7 citations
TL;DR: In this article, the synthesis, purification and subsequent self-assembly of different polyether-based diblock terpolymers in aqueous solutions were reported, showing the formation of branched worm-like structures from previously well defined filomicelles.
7 citations
TL;DR: It was demonstrated the high potential of the ITC to determine critical concentrations and the energies associated with the aggregation of a cationic surfactant and aromatic anions for the formation of WLM.
Abstract: The energy released when tetradecyltrimethylammonium bromide (C14TAB) is combined with different derivatives of chlorobenzoates in an isothermal titration calorimeter (ITC) allows a direct evaluation of the spontaneity of the threading of the aromatic anions into the micellar palisade. The comparison between the enthalpimetric curves with the ones for viscosity of the solutions, hydrodynamic radii of the aggregates (dynamic light scattering experiments), and the fraction of aromatic anions incorporated (diffusion-ordered spectroscopy experiments) allows the establishment of the variations of enthalpy with formation, growth, and decrease of the wormlike micelles (WLMs). The formation of WLMs with C14TAB is very favored (very exothermic) for titrations of chlorobenzoate derivatives which present the chlorine atom in positions 3 or 4 of the aromatic ring. However, the aggregation is highly unfavorable if chlorine is at position 2 of chlorobenzoate. According to the results, the high potential of the ITC to determine critical concentrations and the energies associated with the aggregation of a cationic surfactant and aromatic anions for the formation of WLMs was demonstrated.
7 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