Preparation of Hydrophilic Poly(dimethylsiloxane) Stamps by Plasma-Induced Grafting

Abstract

We report a method to prepare hydrophilic poly(dimethylsiloxane) (PDMS) stamps that could transfer patterns of polar molecules homogeneously in soft lithography. In this method, we demonstrated a twostep procedure by using a mixed gas of argon (Ar) and hydrogen (H2)-based microwave plasma pretreatment to activate PDMS and subsequent acrylonitrile grafting onto PDMS, generating a hydrophilic surface with cyano (-CN) group coatings. The PDMS hydrophilic surface exhibited high affinity for wetting acetonitrile, which is a conventional solvent for DNA synthesis. Acetonitrile droplets possessed contact angles as low as 17 ( 7°on the cyano (-CN) groups grafted PDMS stamps surface. The hydrophilicity was stable and could last for at least 1 month at room temperature. Attenuated total reflectance Fourier transform infrared spectroscopy and X-ray photoelectron spectrum were used to characterize the surface hydrophilization. Such a hydrophilic and inert PDMS stamp showed significance for reactive multilevel fabrications in soft lithography. The possible chemical mechanism for PDMS surface grafting was discussed.

Microcontact Printing: Limitations and Achievements

“…[76][77][78][79][80][81] He and coworkers have developed a method using argon and hydrogen mixed-gas microwave plasma pretreatment and acrylonitrile grafting to prepare stable hydrophilic PDMS surfaces for mCP applications. [82] In our group, we used PDMS stamps with plasma-polymerized allylamine thin films for printing of polar inks. [83] Plasma polymerization led to a homogeneous hydrophilic polymer layer on top of the stamp that remained stable for prolonged periods.…”

Cold Plasma Treatment Effects on the Physicochemical and Biodegradable Properties of a Corn Biomass-containing Polyester Film

“…5B). CP 처리된 CBPE 필름 표면의 조도는 CP 처리의 etching에 의한 것으로 사 료되었다 (34,35). CP 처리는 etching 효과로 고분자의 표면 조도 를 증가시킬 수 있는 것으로 알려져 있다 (36).…”

Scaffold fabrication in a perfusion culture microchamber array chip by O2 plasma bonding of poly(dimethylsiloxane) protected by a physical mask

“…Various methods have been used to produce hydrophilic PDMS surfaces, [16][17][18] UV/ozone oxidation, 19 silanization, [20][21][22] radiation-induced graft polymerization, 23,24 and photoinduced graft polymerization. 25,26 However, the number of applicable methods for fabrication of chips with ECM spots on a PDMS surface inside microchambers is limited.…”