Label-Free Fluorescence Detection of Carbohydrate Antigen 15-3 via DNA AND Logic Gate Based on Graphene Oxide

Background: Molecular logic gate always used fluorescent dyes to realize fluorescence signal. The labeling of the fluorophore is relatively expensive, low yield and singly labeled impuritiesaffects the affinity between the target and the aptamer. Label-free fluorescent aptamer biosensor strategy has attracted widespread interest due to lower cost and simple. Objective: Herein, we have designed a AND logic gate fluorescent aptasensor for detecting carbohydrate antigen 15-3(CA15-3) based on label-free fluorescence signal output. Materials and Methods: A hairpin DNA probe consists of CA15-3 aptamer and partly anti-CA15-3 aptamer sequences as a long stem and G-rich sequences of the middle ring as a quadruplex-forming oligomer. G-rich sequences can fold into a quadruplex by K+, and then G-quadruplex interacts specifically with N-methylmesoporphyrin IX(NMM), leading to a dramatic increase in fluorescence of NMM. With CA15-3 and NMM as the two inputs, the fluorescence intensity of the NMM is the output signal. Lacking of CA15-3 or NMM, there is no significant fluorescence enhancing, and the output of the signal is “0”. The fluorescence signal was dramatically increasing and the output of the signal is “1” only when CA15-3 protein and NMM were added at the same time. Results: This biosensor strategy possessed selectivity, high sensitivity for detecting CA15-3 protein from 10 to 500 U mL-1 and the detection limit was 10 U mL-1, and also showed good reproducibility in spiked human serum. Conclusion: In summary, the proposed AND logic gate fluorescent aptasensor could specifically detect CA15-3.

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A Label-Free Electrochemical Immunosensor for Detection of the Tumor Marker CA242 Based on Reduced Graphene Oxide-Gold-Palladium Nanocomposite

Nanomaterials ◽

10.3390/nano9091335 ◽

2019 ◽

Vol 9 (9) ◽

pp. 1335 ◽

Cited By ~ 2

Author(s):

Xin Du ◽

Xiaodi Zheng ◽

Zhenhua Zhang ◽

Xiaofan Wu ◽

Lei Sun ◽

...

Keyword(s):

Graphene Oxide ◽

Tumor Marker ◽

High Performance ◽

Synthesis Method ◽

Carbohydrate Antigen ◽

Electrochemical Immunosensor ◽

Redox Activity ◽

Label Free ◽

Early Cancer Diagnosis ◽

Reduction Cycle

As a tumor marker, carbohydrate antigen 24-2 (CA242) is a highly accurate and specific diagnostic indicator for monitoring pancreatic and colorectal cancers. The goal of this study was to create a novel label-free electrochemical immunosensor using a nanocomposite glassy carbon electrode for the detection of CA242. Graphene oxide (GO) and polyvinyl pyrrolidone were chosen as the dopants for the preparation of a high-performance reduced-GO-gold-palladium (rGO-Au-Pd) nanocomposite. RGO-Au-Pd was characterized using X-ray diffraction and transmission electron microscopy, revealing that the material exhibited superior electrochemical redox activity and electron transfer ability. The effects of the synthesis method, material concentration, reduction cycle, and pH were investigated to optimize the performance of the immunosensor. As a result of the catalytic activity and biocompatibility of rGO-Au-Pd, the prepared CA242 immunosensor displayed a wide linear range of detection from 0.001 U/mL to 10,000 U/mL with a detection limit of 1.54 × 10−3 U/mL and a sensitivity of 4.24 μA (log10CCA242)−1. More importantly, the immunosensor exhibited satisfactory reproducibility and selectivity when detected CA242 in PBS or human serum. The results of our study provide a platform for the development of novel bioassays for use in early cancer diagnosis and promote the application of biosensing technology in the medical field.

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Simple and Label-Free Electrochemical Immuno Determination of the Gastric Cancer Biomarker Carbohydrate Antigen 72-4 with a Carbon Nanotube-Graphene Oxide Hybrid as the Sensing Platform and Ferrocyanide/Ferricyanide as the Probe

Analytical Letters ◽

10.1080/00032719.2021.2002887 ◽

2021 ◽

pp. 1-12

Author(s):

Cheng Wei ◽

Jun Xiao ◽

Sheng Liu ◽

Zhiwei Wang ◽

Luchuan Chen ◽

...

Keyword(s):

Gastric Cancer ◽

Graphene Oxide ◽

Carbon Nanotube ◽

Carbohydrate Antigen ◽

Cancer Biomarker ◽

Label Free ◽

Sensing Platform

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A label-free logic gate hairpin aptasensor for sensitive detection of ATP based on graphene oxide and PicoGreen dye

Journal of Analytical Science & Technology ◽

10.1186/s40543-021-00262-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Jingjing Zhang ◽

Handan Xu ◽

Chunhui Li ◽

Yilin Wang ◽

Debing Liu ◽

...

Keyword(s):

Graphene Oxide ◽

Detection Limit ◽

Adenosine Triphosphate ◽

Low Cost ◽

Logic Gate ◽

High Sensitivity ◽

Single Strand ◽

Fluorescence Signal ◽

Label Free ◽

Detection Range

Abstract Background In this paper, a simple, enzyme-free, label-free fluorescence, high sensitivity logic gate hairpin aptasensor was developed for adenosine triphosphate (ATP) detection based on graphene oxide (GO) and PicoGreen dye. Methods Using single-strand deoxyribonucleic acid (DNA) and adenosine triphosphate (ATP) as input signal and fluorescence signal as output signal, if single-strand DNA (DNA-L), single-strand DNA (DNA-S), and ATP were present at the same time, one segment of DNA-L formed a hairpin ring with ATP, and the other segment of DNA-L formed a completely complementary hairpin stem with DNA-S. The hairpin DNA was detached from the GO surface, and PicoGreen dye was embedded into the hairpin stem, and the fluorescence signal was enhanced. The molecular logic gate was constructed through the establishment of logic histogram, logic circuit, truth table, and logic formula. The biosensor-related performances including sensitivity, selectivity, and linearity were investigated, respectively. Results We have successfully constructed a AND logic gate. The detection limit of ATP is 138.0 pmol/L (3σ/slope) with detection range of 50–500 nmol/L (R2 = 0.98951), and its sensitivity is 4.748 × 106–6.875 × 108 a.u. (mol/L)−1. Conclusions The logic gate hairpin aptamer sensor has the advantages of high sensitivity, low detection limit, and low cost, and can be successfully applied to the detection of adenosine triphosphate (ATP) in actual human urine samples.

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Recognition of Bimolecular Logic Operation Pattern Based on a Solid-State Nanopore

Sensors ◽

10.3390/s21010033 ◽

2020 ◽

Vol 21 (1) ◽

pp. 33

Author(s):

Han Yan ◽

Zhen Zhang ◽

Ting Weng ◽

Libo Zhu ◽

Pang Zhang ◽

...

Keyword(s):

Self Assembly ◽

Detection Method ◽

Logic Gate ◽

Detection Methods ◽

Label Free ◽

Recognition Method ◽

Operation Pattern ◽

Simple Detection ◽

Dna Tetrahedron ◽

Marker Molecule

Nanopores have a unique advantage for detecting biomolecules in a label-free fashion, such as DNA that can be synthesized into specific structures to perform computations. This method has been considered for the detection of diseased molecules. Here, we propose a novel marker molecule detection method based on DNA logic gate by deciphering a variable DNA tetrahedron structure using a nanopore. We designed two types of probes containing a tetrahedron and a single-strand DNA tail which paired with different parts of the target molecule. In the presence of the target, the two probes formed a double tetrahedron structure. As translocation of the single and the double tetrahedron structures under bias voltage produced different blockage signals, the events could be assigned into four different operations, i.e., (0, 0), (0, 1), (1, 0), (1, 1), according to the predefined structure by logic gate. The pattern signal produced by the AND operation is obviously different from the signal of the other three operations. This pattern recognition method has been differentiated from simple detection methods based on DNA self-assembly and nanopore technologies.

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Label-free electrochemical immunosensor based on gold nanoparticle/polyethyleneimine/reduced graphene oxide nanocomposite for the ultrasensitive detection of cancer biomarker matrix metalloproteinase-1

The Analyst ◽

10.1039/d1an00537e ◽

2021 ◽

Author(s):

Xinke Liu ◽

Lu-Yin Lin ◽

Fu-Yen Tseng ◽

Yu-Cheng Tan ◽

Jian Li ◽

...

Keyword(s):

Graphene Oxide ◽

Matrix Metalloproteinase ◽

Gold Nanoparticle ◽

Reduced Graphene Oxide ◽

Electrochemical Immunosensor ◽

Ultrasensitive Detection ◽

Label Free ◽

Matrix Metalloproteinase 1 ◽

Reduced Graphene ◽

P Matrix

Matrix metalloproteinase-1 (MMP-1) is associated with many types of cancers, including oral, colorectal, and brain cancers. This paper describes the fabrication of an MMP-1 immunosensor based on a gold nanoparticle/polyethyleneimine/reduced...

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