Label-free fluorescence probe based on structure-switching aptamer for the detection of interferon gamma.
A novel label-free fluorescence probe based on structure-switching aptamer was developed for the detection of interferon-gamma (IFN-γ). In this work, a single stranded DNA (ssDNA) with G-rich sequence (aptamer) was folded into secondary G-quadruplex structures in the presence of Na(+) and Mg(2+), thiazole orange (TO) was then intercalated into the G-quadruplex structures, resulting in a high fluorescence emission. The target combined with its aptamer, disrupts G-quadruplex structure and releases TO, resulting in a reduction of fluorescence. Using IFN-γ as the model target, the proposed fluorescence probe shows a linear range from 3.0 to 120 nM with a detection limit of 2.0 nM. The proposed strategy avoids complicated covalent modifications or chemical labeling, and thus offers advantages of simplicity and cost efficiency.
Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources, College of Chemistry and Chemical Engineering, Guangxi Normal University, Guilin, 541004, China. zhaoshulin001@163.com.
Li
L
Pan
Yong
Y
Huang
Changchun
C
Wen
Shulin
S
Zhao
D052157:Aptamers, Nucleotide / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D005456:Fluorescent Dyes / Q000737:chemistry*; D007371:Interferon-gamma / Q000032:analysis*; D015203:Reproducibility of Results; D013194:Staining and Labeling
D052157:Aptamers, Nucleotide; D005456:Fluorescent Dyes; D007371:Interferon-gamma