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Single-particle characterization of A? oligomers in solution.

ABSTRACT: Determining the pathological role of amyloids in amyloid-associated diseases will require a method for characterizing the dynamic distributions in size and shape of amyloid oligomers with high resolution. Here, we explored the potential of resistive-pulse sensing through lipid bilayer-coated nanopores to measure the size of individual amyloid-? oligomers directly in solution and without chemical modification. This method classified individual amyloid-? aggregates as spherical oligomers, protofibrils, or mature fibers and made it possible to account for the large heterogeneity of amyloid-? aggregate sizes. The approach revealed the distribution of protofibrillar lengths (12- to 155 -mer) as well as the average cross-sectional area of protofibrils and fibers.

SUBMITTER: Yusko EC

PROVIDER: S-EPMC3418869 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Single-particle characterization of Aβ oligomers in solution.

Yusko Erik C EC Prangkio Panchika P Sept David D Rollings Ryan C RC Li Jiali J Mayer Michael M

ACS nano 20120621 7

Determining the pathological role of amyloids in amyloid-associated diseases will require a method for characterizing the dynamic distributions in size and shape of amyloid oligomers with high resolution. Here, we explored the potential of resistive-pulse sensing through lipid bilayer-coated nanopores to measure the size of individual amyloid-β oligomers directly in solution and without chemical modification. This method classified individual amyloid-β aggregates as spherical oligomers, protofib ...[more]

PMID: 22686709

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