Polystyrene nanoparticles (PS NPs) are widely used in cell-surface antigen detection, neuronal retrograde tracers and nanoparticle-cell interactions. In microfluidic size sorters, PS NPs are the most frequently-used virus and organelles models. Cells co-culture microfluidic chips and microfluidic size sorters generally have complex channel structures hardly be fabricated by silicon, glass and thermoplastics substrates (PMMA, PC, PS, etc.), however, could easily be fabricated by polydimethylsiloxane (PDMS). According to our findings, commercial PS NPs from dominating companies are adsorbed and absorbed in PDMS seriously, which seriously influence the accuracy of quantitative analysis. And to our best knowledges, methods specialized in these troublesome problems have not been reported yet. In this thesis, we focus on two convenient methods, dynamic surfactant coating and sol-gel coating, to minimize adsorption and absorption of PS NPs in PDMS. The effect of dynamic coating of several frequently-used surfactants (Pluronic® F-127, Pluronic® F108, trition X-100, tween 20 and sodium dodecyl sulfate (SDS)) were investigated and SDS revealed to be the most effective one and the coating concentration was optimized to be 1% (w/w). Solgel coating of silica, titanium and vanadium were also investigated respectively for their effect and vanadium coating performed best. Although adsorption and absorption of different sizes (45, 90, 220 and 370nm) of PS NPs in PDMS could be minimized significantly by simple using of 1% SDS coating or vanadium coating, the problems could not be solved completely. Thus, a combined use of vanadium coating and 1% SDS dynamic coating was investigated and the effect improved significantly and almost prevented adsorption and absorption of PS NPs in PDMS. The combined use of two modifications provide an accessible solution for the application of PS NPs in PDMSbased microfluidic chips. Furthermore, biocompatibility of PDMS was significantly improved after vanadium coating or titanium coating, providing more choose to modify PDMS-based microfluidic chips to conduct biology experiments.

聚苯乙烯納米粒子廣泛應用於細胞表面抗原的檢測、神經逆行示蹤以及納 米粒子-細胞相互作用等研究，同時在微流控粒徑分離晶片上常常被用作模擬病 毒和細胞器大小的模型。微流控多細胞共培養晶片和粒徑分離晶片的軌道結構 通常都比較複雜，難以用矽、玻璃和熱塑性材料（例如：聚甲基丙烯酸甲酯、 聚碳酸酯、聚苯乙烯等）加工而成，然而，能夠很容易地用易於製作複雜結構 的聚二甲基矽氧烷（PDMS）材料製成。根據我們的實驗發現，商品化的聚苯 乙烯納米粒子吸附和滲透到 PDMS 上的情況較為嚴重，這將影響後續實驗定量 分析的準確性。然而，據我們所瞭解，並沒有相關的研究對這個問題提出過針 對性的解決方案。因此在這篇論文中，我們選用了兩種較為簡便的方法：動態 表面活性劑修飾法和溶膠-凝膠修飾法對 PDMS 軌道進行修飾以減少聚苯乙烯納 米粒子在 PDMS 上的吸附和滲透。實驗中初步評價了常用的幾種表面活性劑 （Pluronic® F-127, Pluronic® F108, trition X-100, 吐溫 20 和 十二烷基硫酸鈉 （SDS））動態修飾後納米粒子吸附和滲透在 PDMS 上的情況，發現在這個實 驗中 SDS 是最有效的一種表面活性劑，並確定優化濃度為 1%（w/w）。同時， 本論文也考察了氧化釩、二氧化矽及二氧化鈦溶膠-凝膠法修飾 PDMS 晶片表面 的效果，實驗結果發現氧化釩減少不同粒徑的聚苯乙烯納米粒子在 PDMS 上的 吸附與滲透的效果明顯優於二氧化矽和二氧化鈦。雖然簡單地應用 1% SDS 或 者氧化釩修飾 PDMS 軌道能夠分別顯著地減少 45nm、90nm、220nm 和 370nm 的聚苯乙烯納米粒子吸附和滲透到 PDMS 上，但是問題並沒有被完全地解決。 所以，我們嘗試將這兩種修飾方法結合起來應用，發現幾乎能夠完全地抑制聚 苯乙烯納米粒子吸附及滲透在 PDMS 上，基本上解決了這個問題，為後續聚苯 乙烯納米粒子可以無障礙地應用在 PDMS 上提供了可能性。同時，按照我們的 方法對 PDMS 進行氧化釩修飾或者二氧化鈦修飾後生物相容性明顯提高，為 PDMS 微流控晶片在生物上的應用提供了更多的修飾選擇。