Investigation of Approaches for the Fabrication of Protein Patterns by Scanning Probe Lithography

Abstract

This paper investigates three different approaches to patterning proteins within ultrathin resist layers formed from self-assembled monolayers using scanning probe lithography (SPL) at the submicrometer length scale. The first approach uses a “nanografting” method to pattern a reactive carboxylic acid terminated thiol into a resist composed of a methyl-terminated monolayer. Rabbit IgG antigen is bound to the patterned region, and an immunoassay utilizing direct readout of the topographic change resulting from specific binding of anti-rabbit IgG antibody is performed using scanning force microscopy. To address issues related to nonspecific protein adsorption, the other two approaches investigated the patterned removal of glycol-terminated monolayers by mechanically “scraping” patterns at high tip−sample forces by SPL. Protein attachment to the scraped regions was achieved either through the chemisorption of a disulfide coupling agent or by the direct adsorption of Fab‘-SH antibody fragments. Results obtained from all approaches are presented and compared, and the strengths and weaknesses of each toward fabricating high-density, multiple protein arrays are discussed.

Scanning Probe Nanolithography and Protein Patterning of Low‐Fouling Plasma Polymer Multilayer Films

“…[7] SPM can produce nanometer-sized protein patterns with lateral dimensions as small as 100-200 nm through the anodic oxidation of silicon and metal surfaces. [21][22][23] DPN utilizes a sharp scanning probe tip, coated with chemical molecules, that can write patterns with 15 nm line widths. [9,15,24,25] In addition, SPN, performed by the scratching of gold-thiol self-assembled monolayers (SAMs) has been used to generate protein nanopatterns with lateral dimensions from 10 nm to 1 lm with precise control over the pattern size and geometry.…”

Exploration of Simple Analytical Approaches for Rapid Detection of Pathogenic Bacteria

“…The ultraviolet (UV) irradiation of SAMs has been widely used for creating patterns. 165,182,[184][185][186] The more popular photolithographic technique involves the photooxidation of alkanethiolate monolayers on gold. 185,187 The technique involves UV radiation in the presence of oxygen that converts the gold bound thiolate to various oxygenated forms of sulfur (e.g., RSO3 -).…”

Nanolithography: Towards Fabrication of Nanodevices for Life Sciences

“…Using force-induced SPL methods of nanografting and nanoshaving, Porter and coworkers compared three approaches for protein patterning [78]. They successfully combined force-induced SPL with immobilization of IgG via EDC activation of 11-mercaptoundecanoic acid; through direct adsorption of Fab 0 -SH fragments to nanoshaved regions of an EG 3 -OMe matrix, and through chemisorption of a disulfide coupling agent, DSU.…”