Self-assembly amphiphilic block copolymers

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Alexandridis P, Lindman B (eds) (2000) Amphiphilic block copolymers self assembly and applications. Elsevier, Amsterdam... 

Booth, C, Yu, G.-E. and Nace, V. M. (1997). Block copolymers of ethylene oxide and 1,2-butylene oxide. In Amphiphilic block copolymers self-assembly and applications, (ed. P. Alexandridis and B. Lindman). Elsevier, Amsterdam. 

Malmsten M. Block copolymers in pharmaceutics. In Alexan-dridis P, Lindman B, eds. Amphiphilic Block Copolymers Self Assembly and Applications. Amsterdam, New York Elesvier, 2000 319-346. 

Block Copolymers In solutions, amphiphilic block copolymers self-assemble into a variety of supramolecular micellar nanostructures [163-165]. Micelles form when one block is insoluble or only sparingly soluble in the solvent, whereas the other block is soluble and swollen in the solvent. In order to reduce the interfacial energy of the system, the insoluble block segregates in the core of the micelle. When the... 

Another important factor which is not directly related to the hydrophilicity/lipophilicity ratio of various pluronics but which strongly influences the efflux pump inhibitoiy activity of pluronics is micelle formation. Above a certain concentration, the so called critical micelle concentration (CMC), amphiphilic block copolymers self assemble into micelles. It has been demonstrated, that the efflux pump inhibitory activity of pluronics increases with increasing pluronie concentrations, but only until the CMC is reached. Above the CMC, substrate accumulation in cancer cells could not be further increased or was found to even decrease [37]. Therefore, the occurrence of pluronie unimers can be regarded as the crucial prerequisite for the efflux pump inhibitory activity of pluronics [37]. As one mechanism for efflux pump inhibition has been identified to be ATP depletion, it seems necessary that the pluronie unimers are transported into the cells in order to exert this action. 

Amphiphilic block copolymers self-assemble in selective solvents such as water. Depending on parameters like overall average molecular weight, volume fraction of each block, or effective interaction energy between monomers in the blocks, vesicles with a bilayer shell and a solvent interior volume similar to liposomes are formed. They are often called polymersomes [241]. Such polymersomes in aqueous media have attracted increasing interest due to their enhanced stability compared to classical liposomes and due to the potential to control vesicle properties like bilayer thickness, permeability, or surface functionalities by appropriate chemical copolymer adjustment [242]. 

In solution, amphiphilic block copolymers self-assemble into various morphologies, such as micelles, rods, vesicles, or larger aggregates. A number of factors, including the structure of the amphiphile (chemical constitution and relative block lengths of the individual blocks) and properties of the solution (concentration, pH, temperature, and solvent) affect the size and shape of such aggregates [139]. 

Alexandridis P, Lindman B (eds) (2000) Amphiphilic block copolymers self assembly and applications. Elsevier, Amsterdam Xie HQ, Xie D (1999) Prog Polym Sci 24 275 Riess G (2003) Prog Polym Sci 28 1107 FOrster S, Abetz V, Muller AHE (2004) Adv Polym Sci 166 173 Elias HG (1973) J Macromol Sci Chem 7 601... 

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