ARTICLE pubs.acs.org/Langmuir
High-Fidelity Solvent-Resistant Replica Molding of Hydrophobic Polymer Surfaces Produced by Femtosecond Laser Nanofabrication Carmela De Marco,*,†,‡ Shane M. Eaton,§,‡ Marinella Levi,† Giulio Cerullo,§,^ Stefano Turri,† and Roberto Osellame§ †
Dipartimento di Chimica, Materiali e Ingegneria Chimica “Giulio Natta” and ^Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy § Istituto di Fotonica e Nanotecnologie (IFN)-CNR, Piazza Leonardo da Vinci 32, 20133 Milan, Italy ABSTRACT: We demonstrate that hydrophobic areas formed by femtosecond laser irradiation on poly(methyl methacrylate) (PMMA) and polystyrene (PS) polymer substrates can be faithfully replicated on samples of the same material via a solvent-resistant perfluoropolyether (PFPE) elastomer mold. The replicated PMMA and PS samples show nearly identical micro-nanoscale topography and hydrophobic wetting characteristics as the laser-patterned master substrates. This work combines the femtosecond laser capability of spatially tailoring the wettability with a high-resolution parallel replication method, offering the potential for the efficient production of microfluidic devices with selectively tailored flow behavior.
’ INTRODUCTION Miniaturizing standard biochemical laboratory processes and integrating them on a single lab-on-a-chip (LoC) offers many benefits: the quantity of reagents is smaller, operations are less time-consuming, and measurement sensitivity is improved. A LoC consists of a network of microfluidic channels which are used to manipulate small amounts of liquids (
