环境医学工程教育部重点实验室
纳米金在分析检测中的应用

发布时间: 2016-08-09      访问次数: 636

卫伟教授课题组利用8-OHdG诱导的金纳米颗粒的手性组装,建立了圆二色谱检测8-OHdG的新方法。主要研究了不同尺寸金胶的组装以及不同长度的连接DNA对所组装的金胶二聚体CD信号的影响,得知20nm25nm的金纳米颗粒由35bpDNA连接时,其CD信号最大。我们利用DNA组装的金纳米粒子手性二聚体作为信号分子。当8-OHdG存在时,其于aptamer的亲和力大于aptamer与其互补链的亲和力,金胶二聚体结构被破坏,CD信号减弱。通过条件优化,检测的线性范围是0.05 to 2 nM,检测限可达33 pM,低于大多数关于8-OHdG的检测限。可以定量检测血液中的8-OHdG,对空白血清中做加标回收实验,准确度在92%115%。该研究成果发表在Anal. Chem.10.1021/acs.analchem.6b01258.


原理图

金胶尺寸及其手性组装信号


8-OHdG的检测


金胶二聚体的组装效率及方法的选择性

Table 1 Comparison of analytical performance of various methods for determination of 8-OHdG.

method

system

detection range

detection limit

reference

fluorescence

triplex aptamer sensor

3 ~ 100 nM

2

CV

DNA/grapheme/glassy carbon electrode

5.6 ~ 1155 nM

0.875 nM

12

LSV

poly(3-acetylthiophene)/GCE

0.7 ~ 70 μM

100 nM

13

RLS

conformational switching of aptamer

0.09 ~ 14.1 nM

27 pM

16

amperometry

dendrimer modified electrodes

1.2 nM

41

ECL

CQDs coated Au/SiO2 core-shell NPs

0.7 ~ 70 nM

0.3 nM

42

UV-vis

G-quadruplex/hemin DNAzyme

0.466 ~ 247 nM

141 pM

43

UV-vis

label-free aptamer and unmodified AuNPs

5.6 ~ 282 nM

1.7 nM

44

DPV

poly(3-acetylthiophene)/GCE

0.5 ~ 35 μM

31.3 nM

45

ELISA

a monoclonal antibody

46

DPV

SWCNTs-Nafion/GCE

0.03 ~ 1.25 μM

8.0 nM

47

HPLC/MS

direct injection of urine

0.5 nM

48

CD

chiroplasmonic assemblies of AuNPs

0.05 ~ 2 nM

33 pM

this work

与文献方法的比较

Table 2 Recovery results of 8-OHdG added in 10% human serum samplesa.

Sample number

Added (nM)

Found (nM)

Recovery (%)

RSD (%, n = 5)

1

0

-

-

-

2

0.2

0.21

115

7.27

3

0.4

0.37

92.5

5.66

4

0.6

0.58

96.7

5.25

5

0.8

0.82

103

4.89

6

1.0

1.07

107

6.18

aHuman serum samples are sampling from healthy donors at the Second Affiliated Hospital of Southeast University, Nanjing, China.

空白血清中8-OHdG的检测准确度验证实验




代表论文

Yuanjian Liu, Min Wei, Linqun Zhang, Wei Wei*, Yuanjian Zhang, Songqin Liu. Evaluation of DNA Methyltransferase Activity and Inhibition via Chiroplasmonic Assemblies of Gold Nanoparticles. Chem. Commun.  2015, 51, 76, 14350-14353.

Jingjing Ji, Yuanjian Liu, Wei Wei, Yuanjian Zhang, Songqin Liu*. Quantitation of DNA methyltransferase activity via chronocoulometry in combination with rolling chain amplification. Biosens. Bioelectron. 20168525-31.

Linqun Zhang, Yuanjian Liua, Ying Li, Yuewu Zhao, Wei Wei,* Songqin Liu,* Sensitive electrochemical assaying of DNA methyltransferase activity based on mimic-hybridization chain reaction amplified strategy. Anal. Chim. Acta 2016DOI:10.1016/j.aca.2016.05.044

Bingjing Lv, Min Wei, Yuanjian Liu, Xu Liu, Wei Wei*, Songqin Liu. Ultrasensitive photometric and visual determination of organophosphorus pesticides based on the inhibition of enzyme-triggered formation of core-shell gold-silver nanoparticles. Microchimic Acta. 2016, DOI: 10.1007/s00604-016-1939-8