具近紅外光響應之稠環分子的設計、合成、鑑定與應用

Abstract

近年來，近紅外光波段的材料發展快速，利用該波段具有較深的組織穿透度以及較低背景干擾的特性，可以應用於生物顯影上。本篇論文以推電子基—拉電子基核心—推電子基 (Donor-Acceptor-Donor) 為架構設計出吸收或放光在近紅外光區的有機分子材料，再以中孔洞二氧化矽奈米粒子 (mesoporous silica nanoparticles, MSNs) 作為載體來包覆螢光材料，以利進行生醫應用。 在論文的第一章，將簡述近紅外光波段分子應用於有機光電材料與生物顯影領域的發展。第二章則是以萘二噻吩二亞胺 (naphthodithiophenediimide, NDTI) 作為核心接上不同推電子基團形成 D-A-D 的結構，設計出吸收在近紅外光波段的分子，進一步探討其光物理性質。第三章則分為兩部分，第一部分是以本實驗室所發表的推電子基團苯並[4,5]噻吩並[3,2-b]噻吩並[2,3-d]吡咯 (benzo[4,5]thieno[3,2-b]thieno[2,3-d]pyrrole, BDTP) 出發，引入噻吩設計合成出新的推電子基團苯並[4,5]噻吩並[3,2-b]噻吩並[2',3':4,5]噻吩並[2,3-d]吡咯 (benzo[4,5]thieno[3,2-b]thieno[2',3':4,5]thieno[2,3-d]pyrrole, BTTP)，並探討其在共軛延伸後的性質，第二部分則是以 BDTP 作為推電子基團搭配不同拉電子核心結構，設計出系列 D-A-D 架構的分子，並探討該系列分子的光物理性質。第四章為不同內孔洞修飾之中孔洞二氧化矽奈米粒子的製備，並將本實驗室具有良好放光表現的分子包覆進此奈米載體內，使材料可以進到癌細胞中進行後續應用。

In recent years, organic materials with near-infrared (NIR) response have been developed. Their intrinsic photophysical properties allow them to exhibit not only deep biological tissue penetration but also low background interference. Such characteristics are beneficial for the application in bioimaging. In this study, we report the design, synthesis, and properties of a series of donor-acceptor-donor (D-A-D) type organic molecules that exhibit NIR response. Through preliminary characterizations of the target molecules, several specific molecules were selected and encapsulated into mesoporous silica nanoparticles (MSNs), which act as carrier for further biological applications. In Chapter 1, the development of molecules with NIR response materials used in organic electronics and biomedical fields were briefly described. In Chapter 2, the naphthodithiophenediimide (NDTI) core was selected as the central acceptor connecting with various electron-donating groups for giving D-A-D-configured molecules with NIR absorption. The photophysical properties have been investigated and discussed. In the first part of Chapter 3, we reported the design and synthesis of a new electron-donating group, benzo[4,5]thieno[3,2-b]thieno[2',3':4,5]thieno[2,3-d]pyrrole (BTTP), which was expanded by a thiophene from a reported electron-donating molecule, benzo[4,5]thieno[3,2-b]thieno[2,3-d]pyrrole (BDTP). The electron-donating ability of BTTP was studied through photophysical and electrochemical characterizations. In the second part of Chapter 3, BDTP was selected as the donor to couple with different electron-withdrawing derivatives to afford a series of D-A-D-configured molecules that exhibit NIR absorption. In Chapter 4, MSNs with different interior-surface modifications were prepared, then encapsulated the NIR emitters with excellent fluorescence quantum yields into the well-designed MSNs for future biological applications.