Highly-Selective fluorescent Fe3O4@PPy aptasensor

Zhe Jiao; Xiaolin Zhang; Weibin Chen; Zongning Guo; Binyu Huang; Jiantao Ru; Xuelin Huang; Jinbin Liu

doi:10.1016/j.saa.2024.124447

Highly-Selective fluorescent Fe₃O₄@PPy aptasensor

Spectrochim Acta A Mol Biomol Spectrosc. 2024 May 17:318:124447. doi: 10.1016/j.saa.2024.124447. Online ahead of print.

Authors

Zhe Jiao¹, Xiaolin Zhang², Weibin Chen², Zongning Guo³, Binyu Huang⁴, Jiantao Ru², Xuelin Huang⁵, Jinbin Liu⁶

Affiliations

¹ School of Environment and Civil Engineering, Dongguan Key Laboratory of Low-carbon and Recycling, Dongguan University of Technology, Dongguan 523808, China. Electronic address: jiaoz@dgut.edu.cn.
² School of Environment and Civil Engineering, Dongguan Key Laboratory of Low-carbon and Recycling, Dongguan University of Technology, Dongguan 523808, China.
³ Guangdong Provincial Key Laboratory of Intelligent Port Security Inspection, Guangzhou 510700, China; Huangpu Customs District Technology Center, Dongguan 523000, China.
⁴ Guangdong Provincial Key Laboratory of Intelligent Port Security Inspection, Guangzhou 510700, China.
⁵ Guangdong Provincial Key Laboratory of Intelligent Port Security Inspection, Guangzhou 510700, China; Huangpu Customs District Technology Center, Dongguan 523000, China. Electronic address: 34056583@qq.com.
⁶ Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China. Electronic address: cejbliu@scut.edu.cn.

PMID: 38761471
DOI: 10.1016/j.saa.2024.124447

Abstract

Label-free nucleic acid fluorescent probes are gaining popularity due to their low cost and ease of application. However, the primary challenges associated with label-free fluorescent probes stem from their tendency to interact with other biomolecules, such as RNA, proteins, and enzymes, which results in low specificity. In this work, we have developed a simple detection platform that utilizes Fe₃O₄@PPy in combination with a label-free nucleic acid probe, 1,1,2,2-tetrakis[4-(2-bromo-ethoxy)phenyl]ethene (TTAPE) or Malachite Green (MG), for highly selective detection of metal ions, acetamiprid, and thrombin. Fe₃O₄@PPy not only adsorbs aptamers through electrostatic interactions, π-π bonding, and hydrogen bonding, but also quenches the fluorescence of the TTAPE/MG. Upon the addition of target compounds, the aptasensor separates from Fe₃O₄@PPy through magnetic separation. Moreover, by changing different aptamers, the aptasensor was applied to detect metal ions, acetamiprid, and thrombin, with the turned-on photoluminescence (PL) emission intensity recorded and showing linearity to the concentrations of targets. The robustness of method was demonstrated by applying it to real samples, which included vegetables (for detecting acetamiprid with LODs of 0.02 and 0.04 ng/L), serum samples (for detecting thrombin with LODs of 5.5 and 4.3 nM), and water samples (for detecting Pb²⁺ with an LOD of 0.17 nM). Therefore, due to its impressive selectivity and sensitivity, the Fe₃O₄@PPy aptasensor could be utilized as a universal detection platform for various clinical and environmental applications.

Keywords: Fe(3)O(4)@PPY; Malachite green; Nucleic acid probe; TTAPE.