Fariyal Ahmed

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Controlled release polymer vesicles are prepared using hydrolysable diblock copolymers of polyethyleneglycol-poly-l-lactic acid (PEG-PLA) or polyethyleneglycol-polycaprolactone (PEG-PCL). Encapsulation studies with a common anti-cancer agent, doxorubicin, show loading comparable to liposomes. Rates of encapsulant release from the hydrolysable vesicles are(More)
Cytotoxicity can in principle be maximized if drugs with different activities can be delivered simultaneously to the same cell. However, combination therapy with drugs having distinct properties such as solubility generally requires use of multiple carriers or solvents, limiting the likelihood of simultaneous delivery. In this brief report, we describe the(More)
Carrier-mediated delivery of drugs into the cytosol is often limited by either release from the carrier or release from an internalizing endolysosome. Here, loading, delivery, and cytosolic uptake of drug mixtures from degradable polymersomes are shown to exploit both the thick membrane of these block copolymer vesicles and their aqueous lumen as well as(More)
Polymersomes are self-assembled shells of amphiphilic block copolymers that are currently being developed by many groups for fundamental insights into the nature of self-assembled states as well as for a variety of potential applications. While recent reviews have highlighted distinctive properties - particularly stability - that are strongly influenced by(More)
We present a novel methodology for the conjugation of Pluronic poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) block copolymers with a fluorescein derivative, 5-(4,6-dichlorotriazinyl) aminofluorescein (5-DTAF), at room temperature under aqueous conditions. Two Pluronic block copolymers, F68 with molecular weight (MW) 8400 and P105 with MW(More)
Soft-tissue cells are surprisingly sensitive to the elasticity of their microenvironment, suggesting that traditional culture plastic and glass are less relevant to tissue regeneration and chemotherapeutics than might be achieved. Cells grown on gels that mimic the elasticity of tissue reveal a significant influence of matrix elasticity on adhesion,(More)
The commonly held model for membrane dissolution by detergents/surfactants requires lipid transport from the inner to the outer bilayer leaflet ('flip-flop'). Although applicable to many systems, it fails in cases where cross-bilayer transport of membrane components is suppressed. In this paper we investigate the mechanism for surfactant-induced(More)
Polymersomes are self-assembled polymer shells composed of block copolymer amphiphiles. These synthetic amphiphiles have amphiphilicity similar to lipids, but they have much larger molecular weights, so for this reason--along with others reviewed here--comparisons of polymersomes with viral capsids composed of large polypeptide chains are highly(More)
Assemblies of block copolymer amphiphiles are sometimes viewed as glassy, frozen, or static colloids, especially in strongly segregating solutions. Here, we visualize by fluorescence microscopy and AFM the dynamics and transitions of single cylindrical micelles and vesicles composed of a charged diblock copolymer in water. In mapping the salt- and(More)
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