離子性有機共軛分子之設計與合成及其自組裝奈米螢光球之鑑定與應用

Abstract

本文以有機合成的方式，設計出一系列具有高度螢光量子效率之離子性有機自組裝π-共軛分子，並利用電子顯微鏡（electron microscope）及動態光散射儀（dynamic light scattering）的鑑定，分子可於有機溶劑丙酮下自組裝成粒徑100-400 nm的中空囊泡狀（vesicle-like）奈米球。另外也可藉由改變分子所處之溶劑環境，操縱分子自組裝作用力的平衡，可系統性探討奈米球的生成機制。此外我們嘗試利用共振能量轉移行為，探討離子性奈米球於液相時，自組裝動態平衡關係與其分子間自我辨識的能力。另一方面，透過所謂「非相容溶劑輔助分離法（non-solvent assisted separation method）」可強迫相同自組裝行為之藍綠奈米球於固態玻璃基板上達成分開的目的，可因此探討固態下奈米球間之能量轉移行為。最後與具「自分類（self-sorting）」能力的奈米球系統之球間能量轉移效率進行比較。歸因本π-共軛自組裝奈米球系統之離子特性與在水性條件下穩定存在的優點，我們成功將奈米球引入肺部正常細胞與癌細胞中，並透過共聚焦雷射掃描螢光顯微鏡（confocal laser scanning microscope）觀察其顯影位置。另外可藉由MTT assay探討各分子濃度下之細胞存活能力。而分子間不具自我辨識的能力，可藉由將藍、綠、紅分子以各比例相混，所形成之自組裝奈米球經球內能量轉移行為而放出各種光色，包含白光，達成多光色奈米球顯影的目的。最後以流式細胞儀進行奈米球於細胞內之螢光強度定量分析。

In this thesis, we designed a series of highly fluorescent π-conjugated organic molecules with ionic self-assembly motifs. Through the characterizations of electron microscope and dynamic light scattering, the molecules can spontaneously assemble into hollow vesicle-like nano-spheres with diameter of 100-400 nm in the acetone solutions. Moreover, we could systematically investigate the vesicular mechanism by manipulating the force balance of the self-assembly process in the way of changing solvent environments. In addition, by utilizing the FRET mechanism, we could further probe the dynamic equilibrium of the self-assembly behavior and even molecular self-recognition ability in liquid phase. On the other hand, through the so-called non-solvent assisted separation method we could compel the blue-green nano-spheres with the same self-assembly behavior separating on a solid glass substrate, and therefore explored the inter-spherical energy transfer process in solid state. Finally, we compared the energy transfer efficiencies with the nano-systems that behave the self-sorting ability. Because of the advantageous ionic nature and stability in the aqueous medium, we successfully internalized the nano-spheres into normal and cancer cells of lung tissues through the observation of confocal laser scanning microscope. The cell viability under different molecular concentrations was investigated by MTT assay. Moreover, we could obtain color tunable and even white-light nano-spheres for multi-channel imaging purposes by varying the composition of RGB components through intra-spherical energy transfer process attributed to the lack of molecular self-recognition. Finally, we utilized the flow cytometry to quantify the mean fluorescence intensity of nano-spheres within the living cells.