Photocatalytic Nanolithography of Self-Assembled Monolayers and Proteins


Loading...

Date

2013-09-24

Publication Type

Journal Article

ETH Bibliography

yes

Citations

Altmetric

Data

Abstract

Self-assembled monolayers of alkylthiolates on gold and alkylsilanes on silicon dioxide have been patterned photocatalytically on sub-100 nm length-scales using both apertured near-field and apertureless methods. Apertured lithography was carried out by means of an argon ion laser (364 nm) coupled to cantilever-type near-field probes with a thin film of titania deposited over the aperture. Apertureless lithography was carried out with a helium–cadmium laser (325 nm) to excite titanium-coated, contact-mode atomic force microscope (AFM) probes. This latter approach is readily implementable on any commercial AFM system. Photodegradation occurred in both cases through the localized photocatalytic degradation of the monolayer. For alkanethiols, degradation of one thiol exposed the bare substrate, enabling refunctionalization of the bare gold by a second, contrasting thiol. For alkylsilanes, degradation of the adsorbate molecule provided a facile means for protein patterning. Lines were written in a protein-resistant film formed by the adsorption of oligo(ethylene glycol)-functionalized trichlorosilanes on glass, leading to the formation of sub-100 nm adhesive, aldehyde-functionalized regions. These were derivatized with aminobutylnitrilotriacetic acid, and complexed with Ni2+, enabling the binding of histidine-labeled green fluorescent protein, which yielded bright fluorescence from 70-nm-wide lines that could be imaged clearly in a confocal microscope.

Publication status

published

Editor

Book title

Journal / series

Volume

7 (9)

Pages / Article No.

7610 - 7618

Publisher

American Chemical Society

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

Nanofabrication; Photocatalytic patterning; Near-field lithography; Local probe lithography; Protein patterning; GFP; Monolayers

Organisational unit

03389 - Spencer, Nicholas (emeritus) / Spencer, Nicholas (emeritus) check_circle

Notes

Funding

Related publications and datasets