Development of an Iridium(III) Complex as a G‑Quadruplex Probe and Its Application for the G‑Quadruplex-Based Luminescent Detection of Picomolar Insulin

In this study, an unreported Ir­(III) complex 1 was identified by screening as a versatile G-quadruplex probe. It exhibited highly selective response for different G-quadruplex DNA over double strand, single strand and triplex DNA. Compared with the organic G-quadruplex probe thioflavin T, complex 1...

Full description

Saved in:
Bibliographic Details
Published in:Analytical chemistry (Washington) 2016-01, Vol.88 (1), p.981-987
Main Authors: Wang, Modi, Wang, Wanhe, Kang, Tian-Shu, Leung, Chung-Hang, Ma, Dik-Lung
Format: Article
Language:English
Subjects:
Analytical chemistry
Assaying
Bioassays
Deoxyribonucleic acid
Detection
Displays
DNA
Fluorescent Dyes - chemistry
G-Quadruplexes
Humans
Insulin
Insulin - blood
Iridium - chemistry
Luminescence
Luminescent Measurements
Molecular biology
Molecular Structure
Optimization
Organic chemicals
Organometallic Compounds - chemistry
Strands
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In this study, an unreported Ir­(III) complex 1 was identified by screening as a versatile G-quadruplex probe. It exhibited highly selective response for different G-quadruplex DNA over double strand, single strand and triplex DNA. Compared with the organic G-quadruplex probe thioflavin T, complex 1 displays a longer lifetime, a larger Stokes shift, comparable G-quadruplex/ssDNA enhancement ratios, and higher G-quadruplex/triplex DNA enhancement ratios. In consideration of the encouraging G-quadruplex probe performance of complex 1, we employed 1 to develop a G-quadruplex-based detection system for the detection of insulin as a “proof-of-principle” concept. We also demonstrate an optimization process that enhanced the sensitivity of this sensing assay. Compared to previously reported methods, our “mix-and-detect” detection methodology is easy operated, quick, and cost-effective. A detection limit as low as 80 pM for insulin can be achieved by this sensing approach, with a linear relationship between luminescence intensity and insulin concentration established from 80 pM to 20 nM. Moreover, this assay could work effectively in diluted human serum.
ISSN:0003-2700
1520-6882
DOI:10.1021/acs.analchem.5b04064