Cost-effective and facile fluorescent probes for label-free recognition of chlorpromazine hydrochloride and logic gate operation

Printed circuit boards (PCBs) offer a promising platform for the development of electronics-assisted biomedical diagnostic sensors and microsystems. The long-standing industrial basis offers distinctive advantages for cost-effective, reproducible, and easily integrated sample-in-answer-out diagnostic microsystems. Nonetheless, the commercial techniques used in the fabrication of PCBs produce various contaminants potentially degrading severely their stability and repeatability in electrochemical sensing applications. Herein, we analyse for the first time such critical technological considerations, allowing the exploitation of commercial PCB platforms as reliable electrochemical sensing platforms. The presented electrochemical and physical characterisation data reveal clear evidence of both organic and inorganic sensing electrode surface contaminants, which can be removed using various pre-cleaning techniques. We demonstrate that, following such pre-treatment rules, PCB-based electrodes can be reliably fabricated for sensitive electrochemical biosensors. Herein, we demonstrate the applicability of the methodology both for labelled protein (procalcitonin) and label-free nucleic acid (E. coli-specific DNA) biomarker quantification, with observed limits of detection (LoD) of 2 pM and 110 pM, respectively. The proposed optimisation of surface pre-treatment is critical in the development of robust and sensitive PCB-based electrochemical sensors for both clinical and environmental diagnostics and monitoring applications.

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Plasma enhanced label-free immunoassay for alpha-fetoprotein based on a U-bend fiber-optic LSPR biosensor

RSC Advances ◽

10.1039/c5ra02910d ◽

2015 ◽

Vol 5 (31) ◽

pp. 23990-23998 ◽

Cited By ~ 37

Author(s):

Gaoling Liang ◽

Zhongjun Zhao ◽

Yin Wei ◽

Kunping Liu ◽

Wenqian Hou ◽

...

Keyword(s):

Surface Plasmon Resonance ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Localized Surface Plasmon Resonance ◽

Fiber Optic ◽

Cost Effective ◽

Alpha Fetoprotein ◽

Localized Surface Plasmon ◽

Label Free

A simple, label-free and cost-effective localized surface plasmon resonance (LSPR) immunosensing method was developed for detection of alpha-fetoprotein (AFP).

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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 Biosensor Based on Au@MoS₂–PANI for Escherichia coli Detection

Chemosensors ◽

10.3390/chemosensors9030049 ◽

2021 ◽

Vol 9 (3) ◽

pp. 49

Author(s):

Pushap Raj ◽

Man Hwan Oh ◽

Kyudong Han ◽

Tae Yoon Lee

Keyword(s):

Escherichia Coli ◽

Bacterial Infections ◽

Limit Of Detection ◽

Bacterial Pathogens ◽

Cost Effective ◽

Covalent Immobilization ◽

Label Free ◽

Self Assembled Monolayer ◽

Detection Range ◽

Linear Detection

Bacterial infections have become a significant challenge in terms of public health, the food industry, and the environment. Therefore, it is necessary to address these challenges by developing a rapid, cost-effective, and easy-to-use biosensor for early diagnosis of bacterial pathogens. Herein, we developed a simple, label-free, and highly sensitive immunosensor based on electrochemical detection using the Au@MoS₂–PANI nanocomposite. The conductivity of the glassy carbon electrode is greatly enhanced using the Au@MoS₂–PANI nanocomposite and a self-assembled monolayer of mercaptopropionic acid on the gold nanoparticle surface was employed for the covalent immobilization of antibodies to minimize the nonspecific adsorption of bacterial pathogens on the electrode surface. The biosensor established a high selectivity and sensitivity with a low limit of detection of 10 CFU/mL, and detected Escherichia coli within 30 min. Moreover, the developed biosensor demonstrated a good linear detection range, practical utility in urine samples, and electrode regenerative studies.

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Redox-induced target-dependent ratiometric fluorescence sensing strategy and logic gate operation for detection of α-glucosidase activity and its inhibitor

Dalton Transactions ◽

10.1039/d1dt01299a ◽

2021 ◽

Author(s):

Xucan Yuan ◽

Yi Sun ◽

Pengfei Zhao ◽

Longshan Zhao ◽

Zhili Xiong

Keyword(s):

Redox Reaction ◽

Logic Gate ◽

Sensitive Detection ◽

Ratiometric Fluorescence ◽

Fluorescence Sensing ◽

Gate Operation ◽

Glucosidase Activity ◽

Highly Sensitive ◽

Highly Sensitive Detection ◽

Ratiometric Fluorescence Sensing

A target-dependent ratiometric fluorescence sensing strategy was designed and fabricated based on redox reaction for highly sensitive detection of α-glucosidase (α-Glu) activity and its inhibitor. In this study, silicon quantum...

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Dual-frequency impedance assays for intracellular components in microalgal cells

Lab on a Chip ◽

10.1039/d1lc00721a ◽

2021 ◽

Author(s):

Tao Tang ◽

Xun Liu ◽

yapeng Yuan ◽

Ryota Kiya ◽

Yigang Shen ◽

...

Keyword(s):

Cost Effective ◽

Label Free ◽

Dual Frequency ◽

Cost Effective Approach

Intracellular components (including organelles and biomolecules) at the submicron level are typically analyzed in situ by special preparation or expensive setups. Here, a label-free and cost-effective approach of screening microalgal...

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A Label-Free Fluorescent AND Logic Gate Aptasensor for Carbohydrate Antigen 15-3 Detection Based on Graphene Oxide

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207324666210216095053 ◽

2021 ◽

Vol 24 ◽

Author(s):

Wenxiao Hu ◽

Yafei Dong ◽

Luhui Wang ◽

Yue Wang ◽

Mengyao Qian ◽

...

Keyword(s):

Fluorescent Dyes ◽

Logic Gate ◽

High Sensitivity ◽

Carbohydrate Antigen ◽

Fluorescence Signal ◽

Label Free ◽

Molecular Logic ◽

Long Stem ◽

Middle Ring ◽

Fluorescent Aptasensor

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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Realizing an N-two-qubit quantum logic gate in a cavity QED with nearest qubit--qubit interaction

Quantum Information and Computation ◽

10.26421/qic16.5-6-4 ◽

2016 ◽

Vol 16 (5&6) ◽

pp. 465-482

Author(s):

Taoufik Said ◽

Abdelhaq Chouikh ◽

Karima Essammouni ◽

Mohamed Bennai

Keyword(s):

Quantum Logic ◽

Cavity Qed ◽

Logic Gate ◽

Operation Time ◽

Logic Gates ◽

Initial State ◽

Gate Operation ◽

Quantum Logic Gates ◽

Current State ◽

Phase Gate

We propose an effective way for realizing a three quantum logic gates (NTCP gate, NTCP-NOT gate and NTQ-NOT gate) of one qubit simultaneously controlling N target qubits based on the qubit-qubit interaction. We use the superconducting qubits in a cavity QED driven by a strong microwave field. In our scheme, the operation time of these gates is independent of the number N of qubits involved in the gate operation. These gates are insensitive to the initial state of the cavity QED and can be used to produce an analogous CNOT gate simultaneously acting on N qubits. The quantum phase gate can be realized in a time (nanosecond-scale) much smaller than decoherence time and dephasing time (microsecond-scale) in cavity QED. Numerical simulation under the influence of the gate operations shows that the scheme could be achieved efficiently within current state-of-the-art technology.

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