本文選題：石墨烯/銀納米復(fù)合材料　切入點：絲網(wǎng)印刷電極　出處：《北京印刷學(xué)院》2015年碩士論文

【摘要】：電化學(xué)免疫傳感器，作為分析生物技術(shù)的一個重要領(lǐng)域，能夠針對性地實現(xiàn)對目標物質(zhì)快速的分析和追蹤。但傳統(tǒng)的電化學(xué)免疫傳感器結(jié)構(gòu)復(fù)雜，需要引入標記物用以增強傳感響應(yīng)，不僅耗時耗力、價格高昂，且易因生物分子變性而出現(xiàn)誤差，無標記型電化學(xué)免疫傳感器則無需標記，操作簡單、分析時間快速、測量精確；同時，玻碳電極作為目前常用的基礎(chǔ)電極，在使用時需要反復(fù)打磨，操作繁瑣也造成了檢測誤差，而絲網(wǎng)印刷電極不僅保證了低成本、批量化生產(chǎn)，還實現(xiàn)了電極的微型化、便攜性；此外，傳統(tǒng)電極材料的導(dǎo)電性能較低，需要進行修飾，用以提高其電化學(xué)響應(yīng)性能。 本課題針對上述存在的問題，從電極材料的制備入手，以檸檬酸鈉為銀納米顆粒的保護劑，水合肼、檸檬酸鈉為雙還原劑，在溫和條件下“一鍋”法制備得到石墨烯/銀納米復(fù)合材料。通過調(diào)整投料比，實現(xiàn)對負載銀納米顆粒粒徑(16.6 35.8nm)和分布量(0.16 59.63%)的可控調(diào)節(jié)，結(jié)果顯示該復(fù)合材料具有較高的導(dǎo)電性(rGO固含量為40%時電導(dǎo)率值為35.48S/cm)和電化學(xué)響應(yīng)性(100mV/s掃面速率下峰電流可達45uA)。 采用石墨烯/銀納米復(fù)合材料修飾絲網(wǎng)印刷三電極體系的工作電極，在提高電極表面電子傳輸能力、放大檢測信號的同時，銀納米粒子也為前列腺癌特異性抗體提供了吸附位點，制作了一種無標記型電化學(xué)免疫傳感器。結(jié)果顯示，該傳感器具有快速響應(yīng)性，對前列腺癌特異性抗原的最低檢測限可達0.01ng/mL，線性檢測范圍為1 1000ng/mL，具有良好的特異性、重復(fù)性和穩(wěn)定性。 此外，本論文還制備了一種具有磁響應(yīng)性和生物可降解特性的新型基因載體，通過溶劑熱法制備超小粒徑油相四氧化三鐵納米顆粒，，其粒徑約為4-8nm，飽和磁化強度可達27.27emu/g；再者，采用內(nèi)消旋-2,3-二巰基丁二酸二次交換該納米顆粒表面的油酸分子，獲得水相分散性好的磁性納米顆粒，其飽和磁化強度增至35.67emu/g；最后，由酰胺化反應(yīng)將支鏈型聚乙烯亞胺接枝到水相四氧化三鐵納米顆粒表面，得到具有基因遞送能力的磁響應(yīng)性基因載體，其表面zeta電位可高達52.5±1.94mV，仍具有一定的超順磁性(14.48emu/g)。此外，細胞水平結(jié)果顯示，該基因載體對EGFP質(zhì)粒具有一定的遞送效率。
[Abstract]:Electrochemical immunosensor, as an important field of bioanalysis technology, can be used to analyze and track the target material quickly, but the structure of traditional electrochemical immunosensor is complex. It is necessary to introduce markers to enhance the sensing response, which is not only time-consuming and expensive, but also prone to errors due to biomolecular denaturation, while the unlabeled electrochemical immunosensors need no labeling, so they are easy to operate and analysis time is fast. At the same time, the glassy carbon electrode, as the basic electrode commonly used at present, needs to be polished repeatedly in use, and the complicated operation also causes the detection error, and the screen printing electrode not only guarantees the low cost, but also the mass production. The electrode is miniaturized and portable. In addition, the traditional electrode material has low conductivity and needs to be modified to improve its electrochemical response performance. In order to solve the above problems, starting with the preparation of electrode materials, sodium citrate was used as the protective agent of silver nanoparticles, hydrazine hydrate and sodium citrate were used as double reductants. The graphene / silver nanocomposites were prepared by "one pot" method under mild conditions. By adjusting the feeding ratio, the particle size of loaded silver nanoparticles was 16.6 ~ 35.8 nm) and the distribution of silver nanoparticles was 0.16 ~ 59.63). The results show that the conductivity of the composite is 35.48s / cm when the solid content of rGO is 40) and the peak current of the composite is up to 45uAn at the sweep rate of 100mV / s. The working electrode of the three-electrode system was modified by graphene / silver nanocomposites, which can improve the electronic transmission ability on the electrode surface and amplify the detection signal. Silver nanoparticles also provided an adsorption site for prostate cancer specific antibodies, and an unlabeled electrochemical immunosensor was developed. The results showed that the sensor had rapid response. The minimum detection limit for prostate cancer specific antigen was 0.01ng / mL, and the linear detection range was 1 / 1000ng / mL, which had good specificity, reproducibility and stability. In addition, a novel gene carrier with magnetic response and biodegradability was prepared. The ultrasmall oil phase iron trioxide nanoparticles were prepared by solvothermal method. The particle size was about 4-8 nm, and the saturation magnetization reached 27.27 emu / g. The oleic acid molecules on the surface of the nanoparticles were exchanged twice by using racemic -2o 3-dimercaptosuccinic acid to obtain magnetic nanoparticles with good water dispersion. The saturation magnetization of the nanoparticles increased to 35.67 emu / g, and the saturation magnetization of the nanoparticles was increased to 35.67 emu / g. The branched polyethyleneimine was grafted onto the surface of Fe _ 2O _ 3 nanoparticles in aqueous phase by amidation reaction, and the magnetic responsive gene vector with gene delivery ability was obtained. The surface zeta potential of the vector was as high as 52.5 鹵1.94 MV, and it still had a certain superparamagnetic potential of 14.48 emu / g. Cell level results showed that the gene vector had a certain delivery efficiency to EGFP plasmid.
【學(xué)位授予單位】：北京印刷學(xué)院
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TP212;TB333

【參考文獻】

相關(guān)期刊論文 前1條

1 杜華麗;符雪文;溫永平;仇澤君;熊麗梅;洪年章;楊云慧;;基于石墨烯和金納米籠修飾的無標記型微囊藻毒素免疫傳感器的研制[J];分析化學(xué);2014年05期

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