From Monochrome to Technicolor: Simple Generic Approaches to Multicomponent Protein Nanopatterning Using Siloxanes with Photoremovable Protein-Resistant Protecting Groups

• Published in: Langmuir 2017-09, Vol.33 (35), p.8829-8837
• Main Authors: El Zubir, Osama, Xia, Sijing, Ducker, Robert E, Wang, Lin, Mullin, Nic, Cartron, Michaël L, Cadby, Ashley J, Hobbs, Jamie K, Hunter, C. Neil, Leggett, Graham J
• Format: Article
• Language: English
• Subjects: Adsorption; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Microscopy, Atomic Force; Nanotechnology; Proteins; Siloxanes
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/acs.langmuir.7b01255

We show that sequential protein deposition is possible by photodeprotection of films formed from a tetraethylene-glycol functionalized nitrophenylethoxycarbonyl-protected aminopropyltriethoxysilane (NPEOC-APTES). Exposure to near-UV irradiation removes the protein-resistant protecting group, and allows protein adsorption onto the resulting aminated surface. The protein resistance was tested using proteins with fluorescent labels and microspectroscopy of two-component structures formed by micro- and nanopatterning and deposition of yellow and green fluorescent proteins (YFP/GFP). Nonspecific adsorption onto regions where the protecting group remained intact was negligible. Multiple component patterns were also formed by near-field methods. Because reading and writing can be decoupled in a near-field microscope, it is possible to carry out sequential patterning steps at a single location involving different proteins. Up to four different proteins were formed into geometric patterns using near-field lithography. Interferometric lithography facilitates the organization of proteins over square cm areas. Two-component patterns consisting of 150 nm streptavidin dots formed within an orthogonal grid of bars of GFP at a period of ca. 500 nm could just be resolved by fluorescence microscopy.