Nanoscale protein patterning using self-assembled diblock copolymers.

Nitin Kumar; Jong-in Hahm

doi:10.1021/la050331v

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PubMed · 16008369

Nanoscale protein patterning using self-assembled diblock copolymers.

Nitin Kumar·Jong-in Hahm

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Abstract

Novel methods for immobilizing proteins on surfaces have the potential to impact basic biological research as well as various biochip applications. Here, we demonstrate a unique method to pattern proteins with a nanometer periodicity on silicon oxide substrates using microphase-separated diblock copolymer thin films. We developed a straightforward and effective protein immobilization technique using the microphase-separated domains of polystyrene-block-poly(methyl methacrylate) to localize various model protein molecules such as bovine immunoglobulin G, fluorescein isothiocyanate conjugated anti-bovine immunoglobulin G, and protein G. The self-organizing nature of the diblock copolymer was exploited to produce periodically alternating, nanometer-spaced polymeric domains exposing the two chemical compositions of the diblock to surface. We demonstrate that the model proteins selectively self-organize themselves on the microdomain regions of specific polymer components due to their preferential interactions with one of the two polymer segments. This diblock copolymer-based, self-assembly approach represents a step forward for facile, nanometer-spaced protein immobilization with high areal density and could provide a pathway to high-throughput proteomic arrays and biosensors.

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Microscopy, Atomic Force Nanotechnology Polymethyl Methacrylate Polystyrenes Proteins Journal Article Research Support, Non-U.S. Gov't

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Nitin Kumar, Jong-in Hahm. 2005-07-19. Nanoscale protein patterning using self-assembled diblock copolymers.. https://doi.org/10.1021/la050331v

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