【摘要】：碳量子點(carbon quantum dots, CDs)是2004年發(fā)現(xiàn)的尺寸小于20 nm的新型納米材料。碳量了點熒光明亮、穩(wěn)定性高、無光漂白現(xiàn)象,發(fā)射波長可通過改變材料的粒徑大小、結(jié)構(gòu)成分或摻雜種類來調(diào)控,并具有良好的生物相容性和精確的生物靶向性以及低毒性,因而成為傳統(tǒng)半導(dǎo)體量子點在生物成像、生物標(biāo)記等應(yīng)用中理想的替代物。由于碳量子點制備工藝簡單、生產(chǎn)成木低廉,易于功能化和工業(yè)化,使其在環(huán)境檢測、光催化、光電子器件等眾多領(lǐng)域中展現(xiàn)出巨大的應(yīng)用潛力,給生物醫(yī)學(xué)、光電器件、薄膜顯示等學(xué)科領(lǐng)域帶來新的、廣闊的發(fā)展空間。本文以新鮮檸檬汁/橙汁為碳源,采用水熱法制備碳量子點,對碳量子點的表面形態(tài)、微觀結(jié)構(gòu)、結(jié)晶狀態(tài)及熒光特性進(jìn)行表征和分析,探索碳量子點的發(fā)光機(jī)制和影響因素：并利用碳量子點生物相容性和低細(xì)胞毒性以及優(yōu)異的熒光特性實現(xiàn)了生物成像和肺腺癌細(xì)胞標(biāo)記。研究結(jié)果表明：1.檸檬汁/橙汁水熱法制備熒光碳量子點的最佳工藝參數(shù)為120℃下恒溫150 min。此條件下制備的碳量子點粒徑分布均勻,分散獨立,結(jié)晶度高,穩(wěn)定性好,能長時間穩(wěn)定存在于水溶液中。2.檸檬汁/橙汁碳化合成碳量子點的原理是：檸檬汁/橙汁中的主要成分抗壞血酸、檸檬酸及糖類的碳化形成碳量子點。延長水熱反應(yīng)的時間會引起碳量子點團(tuán)聚、變形和粒徑分布不均等現(xiàn)象。3.用最佳工藝制備的碳量子點晶粒尺寸分布為2～4 nm,平均尺寸約為3 nm,晶格條紋清晰；對紫外光吸收較強(qiáng),吸收峰位于202 nm和290 nm處；此方法制備的碳量子點表面存在大量含氧官能團(tuán),使之易溶于水,并有利于碳量子點表面改性和功能化。4.碳量子點的熒光波長具有激發(fā)光波長依賴的特性,隨著激發(fā)光波長的增加,其熒光發(fā)射峰會發(fā)生小范圍的紅移,最強(qiáng)的熒光發(fā)射峰位于482nm處,呈藍(lán)綠色熒光。將所制備熒光碳量子點用于肺腺癌細(xì)胞標(biāo)記,用生物顯微鏡可觀察到在藍(lán)光激發(fā)下,碳量子點標(biāo)記的肺腺癌細(xì)胞呈清晰的綠色熒光圖像,細(xì)胞輪廓與白光明場像一致。
[Abstract]:Carbon quantum dot (carbon quantum dots, CDs) is a new nanometer material with size less than 20 nm discovered in 2004. Carbon content is bright, stable, photobleaching phenomenon, emission wavelength can be controlled by changing the particle size, structural composition or doping type of materials, and has good biocompatibility, accurate biological targeting and low toxicity. Therefore, it has become an ideal substitute for traditional semiconductor quantum dots in biological imaging, biomarker and other applications. Because of its simple preparation process, cheap wood production, easy functionalization and industrialization, carbon quantum dots have shown great application potential in many fields, such as environmental detection, photocatalysis, optoelectronic devices, and so on. Film display and other disciplines bring new and broad space for development. Using fresh lemon juice / orange juice as carbon source, carbon quantum dots were prepared by hydrothermal method. The surface morphology, microstructure, crystalline state and fluorescence characteristics of carbon quantum dots were characterized and analyzed. To explore the luminescence mechanism and influencing factors of carbon quantum dots (QDs), biocompatibility, low cytotoxicity and excellent fluorescence characteristics of QDs were used to achieve biologic imaging and labeling of lung adenocarcinoma cells. The results of the study show that 1: 1. Preparation of fluorescent carbon Quantum Dots by hydrothermal method of Lemon Juice / Orange Juice: 150 min. at constant temperature of 120 鈩，

本文編號：2223452