本文關(guān)鍵詞： 納米ZnO 浸潤性 蛋白吸附 蛋白分離　出處：《東北師范大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：納米ZnO作為一種具有優(yōu)異光電性能和良好生物相容性的半導(dǎo)體納米材料,在熒光成像、生物檢測等諸多生物醫(yī)學(xué)領(lǐng)域中體現(xiàn)出了巨大的應(yīng)用潛力。在加快其實用化進程中,Zn O與生物物質(zhì)界面間相互作用的研究尤為重要。大量研究表明固體表面浸潤性是影響納米生物界面性質(zhì)的重要因素之一。雖然納米ZnO表面浸潤性已有研究,但是其對蛋白吸附行為的調(diào)控卻鮮有報道。蛋白在固體表面的吸附還將進一步影響細胞的粘附,因此,系統(tǒng)研究納米ZnO表面浸潤性對蛋白吸附的影響規(guī)律并建立相關(guān)模型有助于加深ZnO與生物物質(zhì)作用機制的理解,為新型、高效納米生物醫(yī)用平臺的發(fā)展提供理論與技術(shù)支持。本論文以浸潤性可調(diào)的納米ZnO為研究對象,探究了蛋白與細胞在其表面吸附/粘附規(guī)律,并以此為基礎(chǔ),改進了傳統(tǒng)的蛋白磁分離技術(shù),開發(fā)了基于超疏水納米ZnO界面的高效痕量蛋白分離技術(shù)。具體研究內(nèi)容如下:1.利用紫外光輻射和暗態(tài)存儲等方式調(diào)節(jié)了納米ZnO表面浸潤性,獲得了一系列從超親水到超疏水的納米ZnO。以牛血清白蛋白(BSA)為模型蛋白,系統(tǒng)研究了納米ZnO表面浸潤性對BSA吸附行為的影響。研究結(jié)果表明,由于蛋白吸附位點隨ZnO親水性增強而增加,因此,BSA在納米ZnO表面的吸附量也隨之增加。BSA吸附動力學(xué)測試及紅外光譜表征證實了BSA在納米ZnO表面存在著吸附、脫附與構(gòu)象變化三個過程。BSA吸附與脫附速率隨ZnO表面疏水性的增強而增大,這可能與鍵聯(lián)在ZnO表面的水分子氫鍵網(wǎng)絡(luò)產(chǎn)生的能量勢壘有關(guān)。BSA構(gòu)象變化速率隨納米ZnO疏水性增強而增大,但當(dāng)ZnO表面達到超疏水時,該速率略有減小,這可能是BSA與ZnO間疏水相互作用增強和吸附位點減小共同導(dǎo)致的結(jié)果。軟蛋白BSA在具有不同浸潤性的納米ZnO表面的吸附規(guī)律還適用于硬蛋白(如溶菌酶蛋白)吸附及細胞(如4T1細胞)粘附。這一研究對加深納米生物界面作用機制的理解及納米生物界面材料的選擇、設(shè)計和應(yīng)用提高了重要的理論和實驗參考。2.選用納米ZnO作為痕量蛋白磁分離器壁材料,研究其表面浸潤性對蛋白分離效率的影響。研究結(jié)果表明,蛋白分離效率隨蛋白濃度的降低而減小,蛋白在超疏水納米ZnO上的分離效率優(yōu)于普通商用的塑料、玻璃基底和疏水納米ZnO,尤其在蛋白濃度較低時(≤200μg/mL),超疏水納米ZnO分離效率更具明顯優(yōu)勢。疏水納米ZnO蛋白分離效率低于商用材料,證實了提高痕量蛋白分離效率的關(guān)鍵因素是材料表面浸潤性,而非化學(xué)組成。超疏水納米ZnO蛋白分離效率還與蛋白種類有關(guān),硬蛋白分離回收效率較軟蛋白來說更高。該超疏水ZnO表面適用于分離pH為6.0~8.0,離子強度為0~1mol/mL的痕量蛋白體系的分離。該研究結(jié)果為改進現(xiàn)有痕量蛋白磁分離技術(shù)提供了新思路。
[Abstract]:Nanocrystalline ZnO is a kind of semiconductor nanomaterials with excellent optoelectronic properties and good biocompatibility in fluorescence imaging. Many biomedical fields, such as biological detection, have shown great application potential. It is particularly important to study the interaction between Zno and biomaterial interface in accelerating the practical process. A large number of studies show that solid surface infiltration. Property is one of the most important factors affecting the properties of nanoscale biological interface. Although the surface wettability of nanocrystalline ZnO has been studied, However, the regulation of protein adsorption behavior is rarely reported. The adsorption of protein on solid surface will further affect cell adhesion. A systematic study of the effect of surface wettability on protein adsorption of nanometer ZnO and the establishment of related models will help to deepen the understanding of the mechanism of interaction between ZnO and biomaterials, which is a new type of protein adsorption. The development of high efficiency nano-biomedical platform provides theoretical and technical support. In this paper, we study the adsorption / adhesion of protein and cell on the surface of ZnO. In this paper, the traditional protein magnetic separation technique is improved, and the high efficiency trace protein separation technology based on superhydrophobic nanometer ZnO interface is developed. The specific research contents are as follows: 1. The surface wettability of nanometer ZnO is regulated by ultraviolet radiation and dark state storage. A series of nanocrystalline ZnOs from superhydrophilic to superhydrophobic were obtained. Using bovine serum albumin (BSA) as model proteins, the effects of surface wettability of ZnO on the adsorption behavior of BSA were systematically studied. Because the protein adsorption sites increase with the increase of the hydrophilicity of ZnO, the adsorption capacity of BSA on the surface of nano-BSA is also increased. The adsorption kinetics of BSA on the surface of nano-BSA and the characterization of IR spectra confirm the existence of BSA adsorption on the surface of nano-#en3#. Desorption and conformation change. The adsorption and desorption rate of BSA increases with the increase of hydrophobicity of ZnO surface. This may be related to the energy barrier generated by the hydrogen bond network of water molecules on the surface of ZnO. The conformational change rate of ZnO increases with the increase of hydrophobicity of ZnO nanoparticles, but decreases slightly when the surface of ZnO reaches superhydrophobicity. This may be the result of the enhancement of hydrophobic interaction between BSA and ZnO and the decrease of adsorption sites. The adsorption of soft protein BSA on the surface of nano-sized ZnO with different wettability can also be applied to the absorption of hard protein (such as lysozyme protein). Adhesion to cells (such as 4T1 cells). This study is intended to deepen the understanding of the mechanism of nanoscale biological interface and the selection of nanoscale biomaterials. The design and application improved the important theoretical and experimental reference. 2. Using nanometer ZnO as the wall material of trace protein magnetic separator, the effect of surface wettability on protein separation efficiency was studied. The separation efficiency of protein decreased with the decrease of protein concentration, and the separation efficiency of protein on superhydrophobic nanometer ZnO was better than that of ordinary commercial plastics. The separation efficiency of superhydrophobic nano-ZnO on glass substrate and hydrophobic nano-ZnO, especially when the protein concentration is lower (鈮，

本文編號：1541932