Terminal deoxynucleotidyl transferase (TdT)-catalyzed homo-nucleotides-constituted ssDNA: Inducing tunable-size nanogap for core-shell plasmonic metal nanostructure and acting as Raman reporters for detection of Escherichia coli O157:H7

Yangyang Zhou; Weina Fang; Keqiang Lai; Yongheng Zhu; Xiaojun Bian; Jianlei Shen; Qian Li; Lihua Wang; Weijia Zhang; Juan Yan

doi:10.1016/j.bios.2019.111419

Terminal deoxynucleotidyl transferase (TdT)-catalyzed homo-nucleotides-constituted ssDNA: Inducing tunable-size nanogap for core-shell plasmonic metal nanostructure and acting as Raman reporters for detection of Escherichia coli O157:H7

Biosens Bioelectron. 2019 Sep 15:141:111419. doi: 10.1016/j.bios.2019.111419. Epub 2019 Jun 8.

Authors

Yangyang Zhou¹, Weina Fang², Keqiang Lai¹, Yongheng Zhu¹, Xiaojun Bian¹, Jianlei Shen³, Qian Li³, Lihua Wang², Weijia Zhang⁴, Juan Yan⁵

Affiliations

¹ Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture, Shanghai Engineering Research Center of Aquatic-Product Process & Preservation, College of Food Science and Technology, Shanghai Ocean University, Shanghai, 201306, China.
² Division of Physical Biology & Bioimaging Center, Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China.
³ School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
⁴ Fifth People's Hospital of Shanghai and Institutes of Biomedical Sciences, and State Key Laboratory of Molecular Engineering, Fudan University, Shanghai, 200032, China. Electronic address: weijiazhang@fudan.edu.cn.
⁵ Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture, Shanghai Engineering Research Center of Aquatic-Product Process & Preservation, College of Food Science and Technology, Shanghai Ocean University, Shanghai, 201306, China. Electronic address: j-yan@shou.edu.cn.

PMID: 31203177
DOI: 10.1016/j.bios.2019.111419

Abstract

Core-shell plasmonic metal nanoparticles with interior nanogaps are superior nanostructures owing to their large signal enhancement for Surface enhanced Raman spectroscopy (SERS). Herein, we incorporated Terminal deoxynucleotidyl transferase (TdT)-catalyzed DNA in the preparation of core-shell nanostructures for the detection of Escherichia coli O157:H7 (E. coli O157:H7) cells. The elongated products-homo-nucleotides-composed of long single DNA strands (hn-D) are used not only to induce tunable-size nanogaps but also as Raman reporters with consistent and uniform signal enhancement. Using this synthetic process of hn-D-embedded core-shell nanoparticles (hn-DENPs), we found that the length of hn-D strands affects the size of the nanogap. In addition, performances of the specific Raman imaging of E. coli O157:H7, high detection sensitivity of 2 CFU/mL, and the recovery of 98.1%-105.2% measured in the real food samples, make hn-DENP a biosensor that will be widely used in biological detection.

Keywords: Bacterial detection; Core-shell nanostructures; Nanogap; Surface enhanced Raman spectroscopy (SERS); Terminal deoxynucleotidyl transferase (TdT).

MeSH terms

Biosensing Techniques / methods
DNA Nucleotidylexotransferase / chemistry*
DNA, Single-Stranded / chemistry*
Escherichia coli Infections / microbiology*
Escherichia coli O157 / isolation & purification*
Food Analysis / methods
Gold / chemistry
Humans
Nanostructures / chemistry*
Nanostructures / ultrastructure
Nucleotides / chemistry
Spectrum Analysis, Raman / methods

Substances

DNA, Single-Stranded
Nucleotides
Gold
DNA Nucleotidylexotransferase