本文選題：石墨烯氧化物 + 汞離子��； 參考：《江蘇大學(xué)》2017年碩士論文

【摘要】：汞離子(Hg~(2+))是環(huán)境污染中的重要因素之一,由于該物質(zhì)低濃度即可對(duì)動(dòng)植物帶來(lái)不可逆的影響,經(jīng)過(guò)循環(huán)過(guò)程離子濃度被不斷富集,對(duì)人類(lèi)的身體健康造成不可估量的傷害。Hg~(2+)可以與特異性核酸序列,如多T的DNA序列作用,引起DNA構(gòu)型發(fā)生變化,基于這個(gè)原理一些檢測(cè)方法被發(fā)展,但仍然存在的一些問(wèn)題:有的方法檢測(cè)樣本少、有的假陽(yáng)性信號(hào)率高、有的靈敏性較低等,為解決這些問(wèn)題,將Hg~(2+)特異作用的DNA作為識(shí)別元件結(jié)合石墨烯氧化物(GO)構(gòu)建生物傳感器。生物傳感器是分子生物學(xué)的一種研究工具,基于生物傳感器對(duì)Hg~(2+)進(jìn)行檢測(cè),發(fā)展檢測(cè)的新方法與新技術(shù),進(jìn)行以下幾個(gè)方面的研究:1.GO表面固定多T序列對(duì)汞離子的檢測(cè)。多T的DNA序列作為識(shí)別元件,羧基熒光素(FAM)修飾的DNA序列固定到作為淬滅劑的GO表面,去除沒(méi)有結(jié)合上的DNA,減少了假陽(yáng)性對(duì)檢測(cè)的影響,提高檢測(cè)的靈敏性,檢測(cè)極限為9.37 nM,比物理吸附降低了20%。進(jìn)一步通過(guò)與檢測(cè)序列互補(bǔ)的DNA序列進(jìn)行雙氨基固定,雙氨基修飾的DNA檢測(cè)極限為2.52 nM,降低了75%。2.雙熒光標(biāo)記多T序列對(duì)汞離子的檢測(cè)。用FAM和SBRY Green I兩種熒光染料對(duì)DNA序列標(biāo)記,這兩種熒光基團(tuán)協(xié)同作用,相互促進(jìn)。單氨基修飾的DNA序列結(jié)合雙熒光修飾構(gòu)建的傳感器檢測(cè)極限為0.53nM,雙氨基修飾的DNA檢測(cè)極限為0.43 nM,降低了20%。3.硫代磷酸化(PS)修飾的DNA序列固定到GO表面對(duì)汞離子檢測(cè)。Hg~(2+)能特異性切割PS修飾的DNA,使Hg~(2+)能夠重復(fù)使用,用FAM標(biāo)記的PS修飾的DNA固定在GO表面對(duì)Hg~(2+)檢測(cè)的極限為1.37 nM,比物理吸附法降低了22%。4.硫代磷酸化修飾的DNA序列結(jié)合生物芯片對(duì)汞離子的檢測(cè)。將多個(gè)DNA序列樣品在玻片上進(jìn)行點(diǎn)陣排列,加入Hg~(2+)實(shí)現(xiàn)對(duì)多樣品的檢測(cè)。GO表面物理吸附PS修飾的DNA序列的檢測(cè)極限為3.187 nM,固定PS修飾的DNA序列的檢測(cè)極限為0.79 nM。通過(guò)上述研究,解決現(xiàn)有Hg~(2+)檢測(cè)方法中存在的問(wèn)題,發(fā)展了幾種Hg~(2+)檢測(cè)的新方法與新技術(shù),推動(dòng)食品安全中重金屬檢測(cè)技術(shù)的進(jìn)一步發(fā)展。
[Abstract]:Mercury ion (HG) is one of the important factors in environmental pollution. Because the low concentration of the substance can bring irreversible effects on animals and plants, the ion concentration is continuously enriched through the cycle process.Can act with specific nucleic acid sequences, such as polyT DNA sequences, causing changes in the configuration of DNA. Based on this principle, some detection methods have been developed.But there are still some problems: some methods to detect small samples, some false positive signal rate, some low sensitivity, to solve these problems,The biosensor was constructed by using Hg~(2 (DNA) as recognition element and graphene oxide (GOG).Biosensor is a research tool in molecular biology. The detection of Hg~(2 based on biosensor and the development of new methods and techniques are studied in the following aspects: 1. The detection of mercury ions by multi-T sequences fixed on the surface of go.The polyT DNA sequence was used as the recognition element, and the carboxyfluorescein modified DNA sequence was immobilized to the surface of go as a quenching agent to remove the unbound DNA, thus reducing the influence of false positive on the detection and improving the sensitivity of the detection.The detection limit is 9.37 nm, which is 20% lower than physical adsorption.Further, the DNA sequence complementary to the detection sequence was immobilized with two amino groups. The detection limit of the DNA modified by the double amino group was 2.52 nm, which reduced the detection limit by 75. 2.Detection of mercury ions by double fluorescence labeling multiple T sequences.The FAM and SBRY Green I fluorescent dyes were used to label the DNA sequence. The two fluorescent groups acted synergistically and promoted each other.The detection limit of single amino modified DNA sequence combined with double fluorescence modification was 0.53 nm and the detection limit of double amino modified DNA was 0.43 nm, which decreased 20.3 nm.Thiophosphorylated DNA sequence immobilized on go surface to detect mercury ions. Hgf2) can specifically cleave PS modified DNA so that Hg~(2) can be reused.The detection limit of DNA modified with PS modified by FAM on go surface is 1.37 nm, which is 22. 4% lower than that of physical adsorption method.Thiophosphorylation modified DNA sequence combined with biochip to detect mercury ions.The detection limit of PS modified DNA sequence is 3.187 nm and the detection limit of fixed PS modified DNA sequence is 0.79 nm.Through the above research, the problems existing in the existing Hg~(2) detection methods are solved, and several new methods and technologies of Hg~(2) detection are developed to promote the further development of heavy metal detection technology in food safety.
【學(xué)位授予單位】：江蘇大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類(lèi)號(hào)】：Q503;TP212

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相關(guān)期刊論文 前2條

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