Study of dielectrophoresis effect of dipolar molecules in electric field of nanopore and development of medical diagnostic nanopore sensor

2015 ◽  
Author(s):  
◽  
Kai Tian
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acids ◽  
Early Stage ◽  
Medical Diagnostics ◽  
Nucleic Acid Detection ◽  
Detection Accuracy ◽  
University Of Missouri ◽  
Complex Samples ◽  
Medical Diagnostic ◽  
Polycationic Peptide

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] The nanopore sensor can detect cancer-derived nucleic acid biomarkers such as microRNAs (miRNAs), providing a noninvasive tool potentially useful in medical diagnostics. However, the nanopore-based detection of these biomarkers remains confounded by the presence of numerous other nucleic acid species found in biofluid extracts. Their nonspecific interactions with the nanopore inevitably contaminate the target signals, reducing the detection accuracy. Here we report a novel method that utilizes a polycationic peptide-PNA probe as the carrier for selective nucleic acid detection in the nucleic acids mixture. The cationic probe hybridized with DNA or RNA forms a dipole complex, which can be captured by the pore using a voltage polarity that is opposite the polarity used to capture negatively charged nucleic acids. As a result, non-target species are driven away from the pore opening, and the target sequences can be detected accurately without interference. In addition, we demonstrate that the PNA probe enables to accurately discriminate single-nucleotide difference. Moreover, molecule dynamic simulation is applied to expose the mechanism. Combined with experimental and calculating data, we construct a model to demonstrate that it is universal for all kinds of nucleic acid targets. In sum, this highly sensitive and selective nano-dielectrophoresis approach can be applied to the detection of clinically relevant nucleic acid fragments in complex samples and fulfills the diagnostic of diseases in early stage.

scholarly journals A nuclease protection ELISA assay for colorimetric and electrochemical detection of nucleic acids

2019 ◽  
Vol 11 (8) ◽  
pp. 1027-1034 ◽  
Author(s):  
Jessica E. Filer ◽  
Robert B. Channon ◽  
Charles S. Henry ◽  
Brian J. Geiss
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acids ◽  
Electrochemical Detection ◽  
Nucleic Acid Detection ◽  
Elisa Assay

The NP-ELISA combines traditional nuclease protection with optical and electrochemical enzymatic readout for nucleic acid detection.

Recent advance in exonuclease Ⅲ-assisted target signal amplification strategy for nucleic acid detection

2021 ◽  
Author(s):  
hongyu liu ◽  
Yuhao You ◽  
Youzhuo Zhu ◽  
Heng Zheng
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acids ◽  
Molecular Diagnostics ◽  
Mutation Analysis ◽  
Signal Amplification ◽  
Nucleic Acid Detection ◽  
Target Signal ◽  
Forensic Investigations ◽  
Exo Iii ◽  
Amplification Strategy

Detection of nucleic acids have become significantly important in molecular diagnostics, genetics therapy, mutation analysis, forensic investigations and biomedical development, and so on. In recent years, exonuclease Ⅲ (Exo III)...

A catalytic DNA circuit-programmed and enzyme-powered autonomous DNA machine for nucleic acid detection

The Analyst ◽  
2019 ◽  
Vol 144 (20) ◽  
pp. 5923-5927 ◽  
Author(s):  
Shuang Liu ◽  
Chen Xin ◽  
Xiaoxiao Yu ◽  
Zhenbo Ding ◽  
Shufeng Liu
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acids ◽  
Nucleic Acid Detection ◽  
One Step ◽  
Catalytic Dna ◽  
Dna Machine

A catalytic DNA circuit-programmed and enzyme-powered autonomous DNA machine was proposed for one-step, isothermal and dual-level amplified detection of nucleic acids.

NAIL: Nucleic Acid detection using Isotachophoresis and Loop-mediated isothermal amplification

Lab on a Chip ◽  
2015 ◽  
Vol 15 (7) ◽  
pp. 1697-1707 ◽  
Author(s):  
Mark D. Borysiak ◽  
Kevin W. Kimura ◽  
Jonathan D. Posner
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acids ◽  
Mobile Phone ◽  
Isothermal Amplification ◽  
Nucleic Acid Detection ◽  
Complex Matrices ◽  
Loop Mediated Isothermal Amplification

The NAIL device integrates isotachophoresis and loop-mediated isothermal amplification (LAMP) with mobile phone detection to extract, amplify, and detect nucleic acids from complex matrices in less than one hour.

scholarly journals A case of SARS-CoV-2 carrier for 32 days with several times false negative nucleic acid tests

2020 ◽  
Author(s):  
Lingjie Song ◽  
Guibao Xiao ◽  
Xianqin Zhang ◽  
Zhan Gao ◽  
Shixia Sun ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Clinical Symptoms ◽  
Early Stage ◽  
Antiviral Treatment ◽  
Immune Therapy ◽  
False Negative ◽  
Clinical Manifestations ◽  
Nucleic Acid Detection ◽  
Rt Pcr ◽  
Nucleic Acid Tests

AbstractIn 2019, a novel coronavirus (SARS-CoV-2) was first discovered in Wuhan, Hubei, China, causing severe respiratory disease in humans, and has been identified as a public health emergency of international concern. With the spread of the virus, there are more and more false negative cases of RT-PCR nucleic acid detection in the early stage of potential infection. In this paper, we collected the epidemiological history, clinical manifestations, outcomes, laboratory results and images of a SARS-CoV-2 carrier with no significant past medical history. The patient was quarantined because of her colleague had been diagnosed. After the onset of clinical symptoms, chest CT results showed patchy ground-glass opacity (GGO) in her lungs, but it took a total of nine nucleic acid tests to confirm the diagnosis, among which the first eight RT-PCR results were negative or single-target positive. In addition to coughing up phlegm during her stay in the hospital, she did not develop chills, fever, abdominal pain, diarrhea and other clinical symptoms. Since initial antiviral treatment, the lung lesions were absorbed. But the sputum nucleic acid test was still positive. In combination with antiviral and immune therapy, the patient tested negative for the virus. Notably, SARS-CoV-2 was detected only in the lower respiratory tract samples (sputum) throughout the diagnosis and treatment period. This is a confirmed case of SARS-CoV-2 infection with common symptoms, and her diagnosis has undergone multiple false negatives, suggesting that it is difficult to identify certain carriers of the virus and that such patients may also increase the spread of the SARS-CoV-2.

scholarly journals Evaluation of the auxiliary diagnosis value of antibodies assays for the detection of novel coronavirus (SARS-Cov-2)

2020 ◽  
Author(s):  
Gao Yong ◽  
Yuan Yi ◽  
Li Tuantuan ◽  
Wang Xiaowu ◽  
Li Xiuyong ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Early Stage ◽  
Clinical Information ◽  
Diagnostic Value ◽  
Nucleic Acid Detection ◽  
Course Of Illness ◽  
Combined Use ◽  
Hospitalization Period ◽  
Positive Rate ◽  
Novel Coronavirus

AbstractBackgroundThe spread of an novel coronavirus (SARS-CoV-2, previously named 2019-nCoV) has already taken on pandemic proportions, affecting over 100 countries in a matter of weeks. Elucidating the diagnostic value of different methods, especially the auxiliary diagnosis value of antibodies assays for SARS-CoV-2 infection is helpful for improving the sensitivities of pathogenic-diagnosis, providing timely treatment, and differentiating the infected cases from the healthy, thus preventing further epidemics.MethodsMedical records from 38 patients with confirmed SARS-CoV-2 infection in the Second People’s Hospital of Fuyang from January 22, 2020 to February 28, 2020 were collected and retrospectively analyzed. Specimens including throat swabs, sputum and serum were collected during the hospitalization period, viral RNAs and serum IgM-IgG antibodies to SARS-CoV-2 were measured respectively. The detectability of different methods as well as the auxiliary diagnosis value of antibodies test for SARS-CoV-2 infection were analyzed.ResultsAmong 38 patients, the total seropositive rate for IgM and IgG was 50.0% and 92.1%, respectively. Two patients remained seronegative throughout the course of illness. In the early phase of illness, the RNA test for sputum specimens possessed the highest detectability(92.3%), followed by the the RNA test for throat swabs (69.2%), and the antibodies assays presented lower positive rates(IgM, 23.0%, IgG, 53.8%). While, the sensitivity of antibodies assays overtook that of RNA test since day 8 after onset (IgM, 50.0%; IgG, 87.5%). Of note, the positive rate of throat swabs was only 13.0% for cases in later phase(≥15 d.a.o), and the sensitivities of IgM and IgG rose to 52.2% and 91.3%, respectively. Combined use of antibodies assay and qRT-PCR at the same time was able to improve the sensitivities of pathogenic-diagnosis, especially for the throat swabs group at the later stage of illness. Moreover, most of these cases with undetectable viral RNA in throat swabs specimens at the early stage of illness were able to be IgM/IgG seropositive after 7 days.ConclusionsThe antibodies detection against SARS-CoV-2 offers vital clinical information for physicians, and could be used as an effective supplementary indicator for suspected cases of negative viral nucleic acid detection or in conjunction with nucleic acid detection in the diagnosis of suspected cases.

scholarly journals Analytical Ancestry: “Firsts” in Fluorescent Labeling of Nucleosides, Nucleotides, and Nucleic Acids

2009 ◽  
Vol 55 (4) ◽  
pp. 670-683 ◽  
Author(s):  
Larry J Kricka ◽  
Paolo Fortina
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acids ◽  
Fluorescent Dyes ◽  
Fluorescent Labeling ◽  
Covalent Attachment ◽  
Detection Methods ◽  
Fluorescent Label ◽  
Nucleic Acid Detection ◽  
Fluorescent Labels ◽  
Fluorescent Properties

Abstract Background: The inherent fluorescent properties of nucleosides, nucleotides, and nucleic acids are limited, and thus the need has arisen for fluorescent labeling of these molecules for a variety of analytical applications. Content: This review traces the analytical ancestry of fluorescent labeling of nucleosides, nucleotides, and nucleic acids, with an emphasis on the first to publish or patent. The scope of labeling includes (a) direct labeling by covalent labeling of nucleic acids with a fluorescent label or noncovalent binding or intercalation of a fluorescent dye to nucleic acids and (b) indirect labeling via covalent attachment of a secondary label to a nucleic acid, and then binding this to a fluorescently labeled ligand binder. An alternative indirect strategy involves binding of a nucleic acid to a nucleic acid binder molecule (e.g., antibody, antibiotic, histone, antibody, nuclease) that is labeled with a fluorophore. Fluorescent labels for nucleic acids include organic fluorescent dyes, metal chelates, carbon nanotubes, quantum dots, gold particles, and fluorescent minerals. Summary: Fluorescently labeled nucleosides, nucleotides, and nucleic acids are important types of reagents for biological assay methods and underpin current methods of chromosome analysis, gel staining, DNA sequencing and quantitative PCR. Although these methods use predominantly organic fluorophores, new types of particulate fluorophores in the form of nanoparticles, nanorods, and nanotubes may provide the basis of a new generation of fluorescent labels and nucleic acid detection methods.

scholarly journals Abiotic Fluorescent Receptors for Bioimaging: Sensing of Nucleic Acids

2019 ◽  
Vol 16 (3) ◽  
pp. 235-239
Author(s):  
Masood Ayoub ◽  
Bilal Ahmad Bhat ◽  
Shahjahan Ul Islam ◽  
Syed Masood Ahmad Rizvi ◽  
Qazi Mohd Junaid
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acids ◽  
Related Species ◽  
Living Cells ◽  
Nucleic Acid Detection ◽  
Acid Phosphate ◽  
Bio Imaging ◽  
Nitrogenous Base ◽  
First Time ◽  
Real Time Application

The design and development of synthetic fluorescent molecular architectures for sensing of nucleic acids and related species in living cells is an area of enormous interest. For the first time a novel compilation of single molecular abiotic fluorescent receptors for nucleic acid detection in living cells have been reviewed. Selected reports have been screened and thoroughly discussed which have revealed enormous promise for bio imaging. The mechanistic aspects of nucleic acid, phosphate or nitrogenous base sensing upon encounter with the receptors has been examined under diverse matrices. In addition to the cytotoxicity, specific conditions deciphering suitable and promising results for real-time application have been highlighted.

scholarly journals A general onepot-method for nucleic acid detection with CRISPR-Cas12a

2020 ◽  
Author(s):  
Tang Guanghui ◽  
Jiaojiao Gong ◽  
Lijuan Kan ◽  
Xiuming Zhang ◽  
Ying He ◽  
...  
Keyword(s):  
Reaction Time ◽  
Nucleic Acid ◽  
Nucleic Acids ◽  
Single Copy ◽  
Human Papillomaviruses ◽  
Nucleic Acid Amplification ◽  
Nucleic Acid Detection ◽  
Time Required ◽  
Cis And Trans ◽  
Single Reaction

Abstract CRISPR/Cas12a system has been shown promising for nucleic acid diagnostics due to its rapid, portable and accurate features. In combination with isothermal amplification technology, single-copy sensitivity can be achieved. However, cleavage of the amplicons and primers by the cis- and trans-activity of Cas12a hinders the attempts to integrate the amplification and detection steps into a single reaction. Through phosphorothioate modification of primer and design of crRNA that allow for the cutting site locating at the modified site of the primer, we realized onepot detection of SARS-CoV-2 with single-copy sensitivity. We also identified the activated Cas12a has a much higher affinity to C nucleotide-rich reporter than others. By applying such reporters, we significantly reduced the reaction time required for the lateral-flow readout. Furthermore, to improve the specificity of the strip-based assay, we created a novel reporter and, when combined with a customized strip, the unspecific signal could be completely eliminated. This established system termed Targeting DNA by Cas12a-based Eye Sight Testing in Onepot Reaction (TESTOR) was validated using clinical cervical samples for human papillomaviruses (HPVs) detection. Our system represents a general approach to integrating the nucleic acid amplification and detection into a onepot reaction in CRISPR-Cas systems, highlighting its potential as a rapid, portable and accurate detection platform of nucleic acids.

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