"Click on the bidirectional switch": the aptasensor for simultaneous detection of lysozyme and ATP with high sensitivity and high selectivity.

Feng Chen,Changqun Cai,Chunyan Chen,Xiaoming Chen

doi:10.1038/srep18814

Abstract

A bifunctional and simple aptasensor was designed to one-spot simultaneously detect two analytes, lysozyme and ATP. The aptasensor was obtained by the electronic interaction between methyl violet (MV) and dsDNA. The dsDNA was obtained by hybridization of ATP aptamer and lysozyme aptamer. And we used the resonance light scattering (RLS) technique to detect the concentration of lysozyme and ATP. During the procedure of detection, the aptasensor works like a bidirectional switch, the corresponding side of the dsDNA will open when the target (lysozyme or ATP) “click” the aptamer, which results in corresponding RLS signal change. By the combination of the RLS technique, it is found that the changed RLS intensity was proportional to the concentration of lysozyme and ATP. The mixtures of ATP and lysozyme also met two binary function relations. The results indicated that the aptasensor could achieve simultaneous detection of ATP and lysozyme, the detection limits of ATP and lysozyme could reach 10−11 M and 10−12 M, respectively. The aptasensor shows potential application for small molecule and protein detection by RLS, it could extend the application of RLS technique.

Highlights

A bifunctional and simple aptasensor was designed to one-spot simultaneously detect two analytes, lysozyme and ATP
We reported a simple aptasensor (Fig. 1) for one-spot simultaneous detection of lysozyme and ATP by using resonance light scattering (RLS) technique
Negative induced circular dichroic (CD) signal around 330 nm is observed for the interaction of methyl violet (MV) with dsDNA, which would be expected for an intercalative-binding mode[42,43]

Summary

Introduction

A bifunctional and simple aptasensor was designed to one-spot simultaneously detect two analytes, lysozyme and ATP. Because of the advantages of rapidity and high sensitivity, RLS technique has more widely applications including the detection of DNA11,12, proteins[13,14], small biological molecules[15], and metal ions[16]. All these aptasensors for parallel analysis of different analytes have not used RLS technique. Zhang et al designed a SERS bio-barcodes probe for the detection of the ATP and lysozyme with high sensitivity, but needed multiple amplification steps and one magnetic-separation procedure[38] Compared with these multiplexed detection mothods, our new RLS-based aptasensor exhibited several advantages. This sensor provided a promising potential application for small molecule and protein detection, and extended the application of RLS

Methods

Results

Conclusion