聚二甲基硅氧烷衬底上金岛膜的制备及其荧光增强作用的研究

Gold-on-gold Film Formation on Polydimethylsiloxane Subtrates for Cyanine 5 Fluorescence Enhancement

利用接种-生长法在疏水性高分子聚合物聚二甲基硅氧烷(Polydimethylsiloxane,PDMS)衬底上制备了金岛膜并研究了该金岛膜衬底对于Cyanine 5(Cy5)荧光染料的荧光增强效应。通过氨水调节氯金酸溶液p H值在PDMS衬底上接种Au3+离子,利用硼氢化钠还原Au3+离子在衬底上形成金纳米颗粒种子,之后通过羟胺对于氯金酸的还原作用使得金纳米颗粒生长为金岛并形成金岛膜。利用原子力显微镜、扫描电子显微镜及荧光显微镜等表征手段研究了所用溶液的浓度变化对于金岛膜形貌及其荧光增强效应的影响。采用5 m M氯金酸溶液作为接种母液,1000μM氯金酸/羟胺溶液作为生长母液时可以得到平均面积为92784 nm2的金岛膜,对于衬底的覆盖率达到最大值68.36%,此时能得到对于Cy5荧光染料的最大荧光增强效应。同时对比了相同制备条件下亲水性的玻璃衬底和疏水性的PDMS衬底上金岛膜形貌及其荧光增强效应的异同,发现PDMS衬底上获得的金岛膜具有更好的分散性及更强的荧光增强效果。

Based on seed-growth synthesis method,gold-on-gold(Au/Au)film was coated onto the surface of polydimethylsiloxane(PDMS)substrates,which enhanced the fluorescence of Cyanine 5(Cy5).After pH modification of HAuCl4 solution by ammonium hydroxide,Au3+was bonded on the PDMS substrates and then reduced to Au0 to form Au nanoparticles.Hydroxylamine subsequently deposited more Au3+from HAuCl4 onto Au nanoparticles to grow to Au/Au film.Atomic force microscopy(AFM),scanning electron microscopy(SEM)and fluorescent microscopy were employed toquantitatively characterize the morphology as well as fluorescence enhancement performance of Au/Au films formed under different synthesis conditions.With 5m M HAuCl4 as seeding solution and 1000μM HAuCl4/NH2OH as growth solution,Au islands with average area of 92784 nm2 were obtained and they covered 68.36%area of the PDMS substrate,and this Au/Au film could achieve the maximum fluorescence enhancement performance.The morphology and fluorescence enhancement of the hydrophilic glass substrates and the hydropobic PDMS substrates were compared and better performance was obtained by the hydropobic PDMS substrates.