Photochemical Microcontact Printing by Thiol−Ene and Thiol−Yne Click Chemistry

Abstract

This article describes the microstructured immobilization of functional thiols on alkene- and alkyne-terminated self-assembled monolayers on silicon oxide substrates by photochemical microcontact printing. A photochemical thiol-ene or thiol-yne “click” reaction was locally induced in the area of contact between stamp and substrate by irradiation with UV light (365 nm). The immobilization reaction by photochemical microcontact printing was verified by contact angle measurements, X-ray photoelectron spectroscopy, atomic force microscopy, and time-of-flight secondary ion mass spectrometry. The reaction rate of photochemical microcontact printing by thiol-ene chemistry was studied using time dependent contact angle measurements. The selective binding of lectins to galactoside microarrays prepared by photochemical microcontact printing was also demonstrated. It was found that photochemical microcontact printing results in a high surface coverage of functional thiols within 30 s of printing even for dilute (mM) ink solutions.

Immobilization of Enzymes via Microcontact Printing and Thiol–Ene Click Chemistry

“…21 Increasingly, this bioorthogonal "click reaction" finds application in the conjugation of biomolecules to substrates and scaffolds, 22−28 including photochemical microcontact printing. 24,27 In this Communication we report an easy and fast method to produce enzyme patterns on alkene terminated SAMs on glass surfaces without the need of enzyme modification or coupling reagents (see Figure 1). By using photochemical thiol−ene addition it was possible to form a covalent bond between the alkenes on the substrates and free thiol groups in the native enzymes.…”

Surface Patterning via Thiol‐Yne Click Chemistry: An Extremely Fast and Versatile Approach to Superhydrophilic‐Superhydrophobic Micropatterns

“…Phototriggered thiol-yne reactions have been explored as a viable approach to surface modifi cations, such as using different thiols to modify "yne"-containing polymer brushes, [ 18 ] immobilizing gold nanoparticles on a polymer surface site-specifi cially, [ 19 ] and creating micropatterns on a monolayer by microcontact printing. [ 20 ] To our knowledge, however, this type of functionalization strategy has never been applied to create superhydrophobic-superhydrophilic micropatterns. Here we show that an alkyne functionalized porous polymethacrylate surface could be easily transformed into either a superhydrophobic or superhydrophilic surface under UV irradiation.…”

Carbohydrate, Biomaterials, and Tissue Engineering Applications

“…Moreover, carbohydrates have very strategic locations on the cell surface [17]. Despite their importance, glycans have not been given as much attention as signaling molecules in biomaterial design for tissue engineering and regenerative medicine applications [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. One of the main successful exploitations of carbohydrates in biomaterial design is the creation of galactose-grafted scaffolds to support hepatocyte (liver cell) growth (Sections 16.2.4) [36,37].…”