Polycarbonate bonding assisted by surface chemical modification without plasma treatment and its application for the construction of plastic-based cell arrays

In this paper, we introduce a strategy for adhering two polycarbonate (PC) substrates by embossing them under relatively mild conditions via simple surface chemical pre-coating without plasma treatment. Bonding was achieved by anchoring aminosilanes, specifically those with primary amines, onto the surface of the PC through urethane linkages between the amine functionality of the silane coupling reagent and the carbonyl group of the PC. Next, the terminal silanol groups on the surfaces of the two PC substrates were cross-linked via the formation of SiOSi bonds at a slightly lower temperature (125 C) than the glass transition temperature (T_g) of PC (145 C) and under atmospheric pressure (0.1 MPa). The chemically treated PC surface was characterized by analyzing water contact angle, X-ray photoelectron spectroscopy (XPS), and fluorescence. The bond strength and reliability were investigated by performing pull strength test, static and dynamic leakage tests, and burst test. In addition, since the proposed bonding allowed physical detachment after the bonding, the assembly was used for the selective patterning of Escherichia coli (E. coli) on the PC surface, which proves the ability to use this technology to construct disposable plastic-based array platforms for cell studies and sensor construction in a highly cost-effective manner.