Multifunctional self-assembled monolayers via microcontact printing and degas-driven flow guided patterning

Sang Hun Lee,Bong-Hyun Jun,Seon Joo Park,Jinyeong Kim,Oh Seok Kwon,Won-Yeop Rho

doi:10.1038/s41598-018-35195-9

Abstract

Soft lithography-based patterning techniques have been developed to investigate biological and chemical phenomena. Until now, micropatterning with various materials required multiple procedural steps such as repeating layer-by-layer patterning, aligning of stamps, and incubating printed inks. Herein, we describe a facile micropatterning method for producing chemically well-defined surface architectures by combining microcontact (µCP) and microfluidic vacuum-assisted degas-driven flow guided patterning (DFGP) with a poly(dimethylsiloxane) (PDMS) stamp. To demonstrate our concept, we fabricated a bi-composite micropatterned surface with different functional molecular inks such as fluorescein isothiocyanate labelled bovine serum albumin (FITC-BSA) and polyethylene glycol (PEG)-silane for a biomolecule array, and 3-aminopropyltriethoxysilane (APTES) and PEG-silane pattern for a self-assembled colloid gold nanoparticle monolayer. With a certain composition of molecular inks for the patterning, bi-composite surface patterns could be produced by this µCP-DFGP approach without any supplementary process. This patterning approach can be used in microfabrication and highly applicable to biomolecules and nanoparticles that spread as a monolayer.

Highlights

Micropatterns are widely used in various research fields such as tissue engineering, developing bio-chips or sensors, etc[1,2,3,4]
Prior to 1st ink patterning, the PDMS stamp was soaked in a fluorescein isothiocyanate (FITC)-labelled BSA (FITC-BSA) and placed on a glass slide for 5 min
After that the PDMS stamp was degassed in a vacuum desiccator for 15 min, and the 2nd ink for passivation was dispensed at the opening of an inlet with a micropipette

Summary

Introduction

Micropatterns are widely used in various research fields such as tissue engineering, developing bio-chips or sensors, etc[1,2,3,4]. After completion of a μCP process with 1st ink, 2nd ink can be aspired by DFGP through microfluidic channels in the free space of a PDMS stamp. We capitulated the use of DFGP based on unique characteristics of the PDMS which is a solubility of gas for fluid actuation without any surface modification of substrate for capillary force-driven flow.

Results

Conclusion