中文摘要：

研究了一种基于紫外光/臭氧（UV/O3）表面改性和硅烷化技术的聚二甲基硅氧烷（PDMS）与聚苯乙烯（PS）的不可逆封合的新方法.首先,用UV/O3处理PS使其表面产生羟基、羧基等极性基团;然后用3-氨丙基三乙氧基硅烷（APTES）对UV/O3处理后的PS硅烷化,使其表面形成氨丙基硅分子链;再将硅烷化后的PS与拟封合的PDMS同时用UV/O3处理,使两者表面均产生硅羟基.最后将处理后的PDMS与PS贴合,通过硅羟基之间的缩合实现两者的不可逆封合.以接触角、XPS和ATR-FT-IR对封合过程进行表征.封合的PDMS-PS复合芯片可承受大于0.5 MPa的压强.采用该方法制备了PDMS-PS复合微流控芯片用于HeLa细胞的培养.实验表明,HeLa细胞在PDMS-PS复合芯片通道内的生长状况大大优于在全PS芯片、略好于在全PDMS芯片内的生长状况.

英文摘要：

In some circumstances, hybrid polymer microfluidic chips composed of both elastic, gas-permeable polydi- methylsiloxane （PDMS） and rigid plastics are needed. However, it is quite difficult to bond PDMS irreversibly to plastics such as polystyrene （PS）. In this article, a facile method for irreversible bonding of PDMS to PS was proposed based on UV/O3-assisted surface modification in combination of surface silanization. Firstly, a PS sheet was exposed to UV/O3 to produce oxygen-containing polar moieties, such as hydroxyl and carboxvlic acid, on its surface. Secondly, the UV/O3 treated FS sheet was silanized with （3-aminopropyl）triethoxysilane （APTES） via the reaction between the oxygen-containing polar moieties on the PS surface and the molecules of APTES. Thirdly, the silanized-PS sheet and the PDMS substrate with micro channel network were treated with UV/O3 again to generate silanol moieties on both surfaces. Finally, the UV/O3 treated PDMS was immediately brought intimate contact with the UV/O3 treated silanized-PS, and irreversible bonding of PDMS with PS occurred after putting the PDMS-PS complex at room temperature for 1 h through the condensation reaction between silanol moieties. Contact angle measurement, X-ray photoelectron spectroscopy, total reflection Fourier transformation infra- red spectrometer were applied to characterize the surface chemistry of the PS during the UV/O3 treatment and silanization. The hybrid PDMS-PS microfludic chips prepared with the established method can bear a gas pressure higher than 0.5 MPa and a water stream at a flow rate higher than 170 I~L/min （the test channels were 2.5 cm in the length, 50 lam in the width, 200 ~m in the depth）. A hybrid PDMS-PS microfluidic chip composed of gas-permeable PDMS substrate with channel net- work and excellently biocompatible PS cover sheet was fabricated for cell culture. The experimental results showed that HeLa cells cultured in the hybrid PDMS-PS microchip grew much better than those cultured in the full PS microch