A label-free fluorometric assay for actin detection based on enzyme-responsive DNA-templated copper nanoparticles

Quanwei Song; Lixia Yang; Hongkun Chen; Rong Zhang; Na Na; Jin Ouyang

doi:10.1016/j.talanta.2017.06.031

A label-free fluorometric assay for actin detection based on enzyme-responsive DNA-templated copper nanoparticles

Talanta. 2017 Nov 1:174:444-447. doi: 10.1016/j.talanta.2017.06.031. Epub 2017 Jun 12.

Authors

Quanwei Song¹, Lixia Yang², Hongkun Chen³, Rong Zhang⁴, Na Na⁵, Jin Ouyang⁶

Affiliations

¹ State Key Laboratory of Petroleum Pollution Control, Beijing 102206, China; CNPC Research Institute of Safety and Environment Technology, Beijing 102206, China; Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China.
² Beijing Key Laboratory of Metal Material Characterization, Central Iron and Steel Research Institute, Beijing 100081, China.
³ State Key Laboratory of Petroleum Pollution Control, Beijing 102206, China; CNPC Research Institute of Safety and Environment Technology, Beijing 102206, China.
⁴ CNPC Research Institute of Safety and Environment Technology, Beijing 102206, China.
⁵ Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China.
⁶ Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China. Electronic address: jinoyang@bnu.edu.cn.

PMID: 28738606
DOI: 10.1016/j.talanta.2017.06.031

Abstract

Herein, we develop a fluorescent strategy for label-free detection of actin by the in situ formation of double-stranded DNA (dsDNA) templated copper nanoparticles (CuNPs) and the digestion capability of deoxyribonuclease I (DNase I). In this design, the introduction of actin can effectively hinder the enzymic digestion owing to the exceptional target-mediated conformational structure between actin and DNase I. Consequently, the remaining adenine-thymine-rich dsDNA can act as an efficient template for fluorescent CuNPs (λ_ex = 340nm, λ_em = 585nm) with a Mega-Stokes shifting (245nm). This novel fluorescent strategy exhibits several advantages such as low-cost and environmental-friendly, because it does not require the toxic organic dyes and laborious procedures. Under optimized experimental conditions, this method realizes a turn-on selective and sensitive response for actin with a detection limit of 0.12μgmL^-1 and a detection capability in complex biological media with satisfactory results.

Keywords: Actin; Copper nanoparticles; DNA; Fluorescence; Lable-free.

MeSH terms

Actins / analysis*
Actins / chemistry
Base Sequence
Biosensing Techniques / methods*
Copper / chemistry*
DNA / chemistry
DNA / genetics
DNA / metabolism*
Deoxyribonuclease I / metabolism*
Feasibility Studies
Fluorometry / methods*
Limit of Detection
Metal Nanoparticles / chemistry*
Models, Molecular
Nucleic Acid Conformation
Protein Conformation

Substances

Actins
Copper
DNA
Deoxyribonuclease I