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Polymers and Self Assembly: From Biology to Nanomaterials Poster Session II

1-POS

Board 1

Single Protein Nanopore as Mass Spectrometer to Polyvinylpyrrolidone

Juliana P. Aguliar

, Sheila M. Barros, Dijanah C. Machado, Janilson J. Silva Junior, Maria C.

Araujo Melo, Claudio Rodrigues

Universidade Federal de Pernambuco, Recife, Brazil.

Synthetic high-molecular polymers are widely applied in biochemistry, biology and medicine.

Many of these applications require a detailed understanding of the structure, morphology and

chemical interactions of these compounds under confinement and in aqueous solution. Poly-N-

vinylamides such as poly(vinylpyrrolidone) (PVP) are highly water soluble synthetic polymers

with a broad mass distribution. PVP is a versatile polymer with innate surface activity. It is very

difficult to accurately assay due to its wide molecular weight range and amphiphilic nature.

There are a number of analytical methods available for the analysis of synthetic polymers. But

analysis of PVP has some difficulty. The classical methods don’t differentiate between unique

oligomers present in a sample, and don’t distinguish impurities and/or additives. Nanometer

scale pores, including nanopore formed by

Staphylococcus aureus

α-toxin(α-HL), can be used to

detect and quantify nucleic acids, proteins, and synthetic polymers. Binding of analytes to

nanopore is random and reversible, and it causes characteristic fluctuations in the ionic current.

For this reason, single nanopores inserted in thin membranes have recently been referred to as

stochastic biosensors. Stochastic biosensing is an approach that relies on the observation of

individual binding events between analyte molecules and a single receptor. Recently we had

demonstrated that size of individual molecules in polydisperse polyethileneglycol (PEG1500)

sample is achievable with a single protein nanopore. The results are similar to MALDI-TOF

spectrograms. This study aims to apply the nanopore based method to PVP analyzer. PVP was

chosen because it wide applicability in pharmaceutical, cosmetic and food industries. We

demonstrated that α-HL nanopore is able to detect PVP and could be used as mass spectrometer

to this polymer and proposed nanopore based biosensor for molecular mass measurement and/or

monitoring different polymers in aqueous solutions.