36 results on '"Lingwen Zeng"'
Search Results
2. Click Chemistry-Mediated Particle Counting Sensing via Cu(II)-Polyglutamic Acid Coordination Chemistry and Enzymatic Reaction
- Author
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Zhilong Wang, Luyu Wei, Lingwen Zeng, Niu Feng, Jianjun Chen, and Yiping Chen
- Subjects
Polyglutamic Acid ,Alkynes ,Click Chemistry ,Biosensing Techniques ,Copper ,Analytical Chemistry - Abstract
An electrical resistance-based particle counter (ERPC) with simple operation and high resolution has proved to be a promising biosensing toolkit, whereas amplification-free ERPC biosensors are incapable of analyzing trace small molecules due to their relatively low sensitivity. In this work, click chemistry-mediated particle counting sensing of small-molecule hazards in food samples with high sensitivity was developed. In this strategy, unbound alkyne-functionalized polystyrene microspheres were collected by magnetic separation from the copper-ion-mediated click reaction between alkyne-functionalized polystyrene microspheres and azido-functionalized magnetic beads, which could be used as signal probes for the readout. This click chemistry-mediated ERPC biosensor converts the detection of targets to the quantification of copper ions or ascorbic acid by performing competitive immunoassay-based coordination chemistry and enzymatic reaction, respectively. The sensitivity of the ERPC biosensor has been improved by an order of magnitude due to the signal amplification effects of click chemistry, coordination adsorption, and enzyme catalysis. Furthermore, because of the efficient separation and enrichment of immunomagnetic beads and the robustness of click chemistry, the interference from food matrixes and immunoassay is effectively reduced, and thus, our strategy is exceedingly suitable for detecting trace targets in complex samples.
- Published
- 2022
3. A lateral flow biosensor based on gold nanoparticles detects four hemorrhagic fever viruses
- Author
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Lingwen Zeng, Jin Zhao, Shuting Fang, Yujie Liu, and Zhixu He
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General Chemical Engineering ,Metal Nanoparticles ,Biosensing Techniques ,Dengue virus ,medicine.disease_cause ,01 natural sciences ,Analytical Chemistry ,law.invention ,Viral hemorrhagic fever ,03 medical and health sciences ,law ,medicine ,Humans ,Pathogen ,Polymerase chain reaction ,030304 developmental biology ,0303 health sciences ,biology ,business.industry ,010401 analytical chemistry ,General Engineering ,Dengue Virus ,medicine.disease ,Hemorrhagic fever virus ,Virology ,0104 chemical sciences ,Colloidal gold ,Hemorrhagic Fever Virus, Crimean-Congo ,biology.protein ,Gold ,Antibody ,business ,Biosensor - Abstract
The pathogen of viral hemorrhagic fever (VHF), which is harmful to human health, is a hemorrhagic fever virus. Clinicians have long needed convenient and sensitive point-of-care rapid diagnostic tests (RDTs) for hemorrhagic fever viruses. Commonly used methods for pathogen detection rely on conventional culture-based tests, antibody-based assays and polymerase chain reaction (PCR)-based techniques. However, these methods are costly, laborious and time-consuming. Herein, we present a simple and sensitive biosensor for the rapid detection of hemorrhagic fever viruses. For this assay, we develop lateral flow biosensors (LFBs) based on magnetic beads and nicking enzyme-assisted isothermal strand-displacement amplification (SDA) for the detection of hemorrhagic fever viruses. The detection limit of this assay is 10 fM.
- Published
- 2020
4. A rapid and sensitive CRISPR/Cas12a based lateral flow biosensor for the detection of Epstein–Barr virus
- Author
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Wei Chen, Yuxia Zhang, Ting Yuan, Rong Zeng, Zhiyuan Li, Lingwen Zeng, Omar Mukama, Jean de Dieu Habimana, Yinghui Zhang, Zhixu He, and Chengrong Nie
- Subjects
Epstein-Barr Virus Infections ,Herpesvirus 4, Human ,Biosensing Techniques ,In situ hybridization ,medicine.disease_cause ,01 natural sciences ,Biochemistry ,Virus ,Analytical Chemistry ,law.invention ,03 medical and health sciences ,chemistry.chemical_compound ,Plasmid ,law ,Electrochemistry ,medicine ,Humans ,Environmental Chemistry ,CRISPR ,Clustered Regularly Interspaced Short Palindromic Repeats ,Spectroscopy ,Polymerase chain reaction ,030304 developmental biology ,0303 health sciences ,Chemistry ,010401 analytical chemistry ,Nasopharyngeal Neoplasms ,medicine.disease ,Molecular biology ,Epstein–Barr virus ,0104 chemical sciences ,Nasopharyngeal carcinoma ,DNA, Viral ,CRISPR-Cas Systems ,DNA - Abstract
Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumors in the world, and several studies have associated Epstein-Barr virus (EBV) with NPC occurrence and development. EBV-PCR (polymerase chain reaction), in situ hybridization and immunoassays are the most common methods for NPC identification. However, these approaches have drawbacks, which include tedious procedures and false results. Therefore, a rapid, accurate, and sensitive clinical diagnostic method for the prognosis of EBV-related diseases is needed. In this study, we developed a simple and sensitive approach for EBV detection based on the combination of CRISPR-Cas12a and a lateral flow biosensor (LFB). Cas12a exhibits collateral cleavage propensity of both target DNA and any single-stranded(ss) DNA in the vicinity (herein referred to as a reporter). The LFB test line contained an ssDNA probe complementary to the reporter. In the presence of the target, Cas12a trans-cleaved the ssDNA reporter, which resulted in the inability of cleaved sequences to bind the LFB test line. With a PCR pre-amplification of the target (45 min), the assay achieved a sensitivity of 7.1 × 10-14 M (∼42 000 copies per μl) both in plasmid and plasmid-spiked samples. The assay attained a high specificity in the presence of various bacteria and applicability in EBV Burkitt's lymphoma serum samples. This method could be applied for the detection of EBV and other infectious diseases.
- Published
- 2020
5. An ultrasensitive and specific point-of-care CRISPR/Cas12 based lateral flow biosensor for the rapid detection of nucleic acids
- Author
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Gaëlle Guiewi Makafe, Jinghua Wu, Zhijian Yi, Jiaxin Liu, Qiongxin Liang, Ning Xu, Lingwen Zeng, Zhiyuan Li, Omar Mukama, Yujie Liu, Yumei Liu, Xuewen Lu, and Muzammal Hussain
- Subjects
DNA, Bacterial ,Point-of-Care Systems ,Biomedical Engineering ,Biophysics ,DNA, Single-Stranded ,02 engineering and technology ,Biosensing Techniques ,01 natural sciences ,Sensitivity and Specificity ,Plasmid ,Nucleic Acids ,Electrochemistry ,CRISPR ,Effector ,Chemistry ,Hybridization probe ,010401 analytical chemistry ,General Medicine ,021001 nanoscience & nanotechnology ,DNA extraction ,0104 chemical sciences ,Biochemistry ,Molecular Diagnostic Techniques ,Nucleic acid ,Naked eye ,CRISPR-Cas Systems ,0210 nano-technology ,Biosensor ,Nucleic Acid Amplification Techniques ,Biotechnology - Abstract
CRISPR/Cas systems have displayed remarkable potential in developing novel biosensing applications for nucleic acid detection owing to the collateral cleavage activity of Cas effector proteins (Cas12, Cas13, etc.). Despite tremendous progress in recent years, the existing CRISPR/Cas based biosensing platforms have several limitations, including reliance on proper amplification methods, expensive fluorescence detection equipment, or lateral flow biosensor (LFB). Herein, we report a simple, inexpensive, and ultrasensitive DNA probe based LFB with C RISPR/Cas and loop-mediated I sothermal A mplification (namely CIA). The concept behind this approach is a non-detectable test line on the LFB when the Cas effector protein collaterally cleaves the cognate target and an ssDNA reporter sequence. The CIA based LFB can detect as low as a single copy cloned Pseudomonas aeruginosa acyltransferase gene, 1 cfu/ml plasmid containing E. coli DH5α pure cultures, as well as clinical samples without DNA extraction/purification or advanced apparatuses. No cross-reactivity with other non-target bacteria was observed. The naked eye result readout was obtained in 15 min of LAMP amplification, 30 min of Cas12 reaction, and 5 min of LFB readout. This platform is robust and of low cost for on-site testing.
- Published
- 2019
6. An enzyme-free DNA circuit for the amplified detection of Cd
- Author
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Jiafeng, Pan, Lingwen, Zeng, and Junhua, Chen
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G-Quadruplexes ,Spectrometry, Fluorescence ,Limit of Detection ,Biosensing Techniques ,DNA ,Aptamers, Nucleotide ,Nucleic Acid Amplification Techniques ,Sensitivity and Specificity ,Cadmium ,Fluorescent Dyes - Abstract
An enzyme-free DNA circuit was designed for the amplified detection of Cd2+ based on hairpin probe-mediated toehold binding and branch migration. A Cd2+-specific aptamer was used to recognize Cd2+ and a G-quadruplex was used to report the detection signal. The assay is sensitive, with a detection limit of 5 pM.
- Published
- 2019
7. A highly sensitive and specific lateral flow aptasensor for the detection of human osteopontin
- Author
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Wei Wu, Lingwen Zeng, Yumei Liu, Omar Mukama, Yujie Liu, Jinghua Wu, Jiaxin Liu, and Xuewen Lu
- Subjects
Aptamer ,02 engineering and technology ,Biosensing Techniques ,01 natural sciences ,Antibodies ,Analytical Chemistry ,stomatognathic system ,Humans ,Osteopontin ,biology ,Chemistry ,010401 analytical chemistry ,Aptamers, Nucleotide ,021001 nanoscience & nanotechnology ,Molecular biology ,Recombinant Proteins ,0104 chemical sciences ,Highly sensitive ,Test line ,HEK293 Cells ,Colloidal gold ,Biotinylation ,biology.protein ,Biomarker (medicine) ,Nanoparticles ,Gold ,0210 nano-technology ,Biosensor - Abstract
The rapid determination of human osteopontin (OPN) protein, a potential cancer biomarker, holds substantial promise for point-of-care diagnostics and biomedical applications. To date, most reported platforms for OPN detection are apparatus-dependent, time-consuming, and expensive. Herein, we established a lateral flow biosensor (LFB) for OPN detection. A biotinylated aptamer was used for OPN pre-capture from samples, an antibody for OPN was immobilized on the test line for a second specific target identification, and streptavidin-modified gold nanoparticles were sprayed on the conjugation pad for color detection. This LFB achieved as low as 0.1 ng mL−1 OPN sensitivity with a good dynamic detection between 10 and 500 ng mL−1 within 5 min. Intriguingly, the LFB allowed a qualitative and semi-quantitative detection of OPN in serum at clinically cut-off levels as in cancer patients, and can discriminate OPN from interfering proteins with high specificity. Thus, it is a promising alterative approach for point-of-care OPN screening and detection.
- Published
- 2019
8. Autocatalytic DNA circuit for Hg
- Author
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Danhua, Zhou, Lingwen, Zeng, Jiafeng, Pan, Qiong, Li, and Junhua, Chen
- Subjects
G-Quadruplexes ,Exodeoxyribonucleases ,Base Sequence ,Limit of Detection ,Water ,Biosensing Techniques ,DNA, Catalytic ,Mercury - Abstract
Utilizing G-quadruplex as the signal report probe, an ultrasensitive and label-free autocatalytic DNA circuit for Hg
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- 2019
9. Highly Sensitive Aptasensor for Trace Arsenic(III) Detection Using DNAzyme as the Biocatalytic Amplifier
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Chengshuai Liu, Danhua Zhou, Junyu Gong, Lingwen Zeng, and Junhua Chen
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Aptamer ,Deoxyribozyme ,Biosensing Techniques ,010402 general chemistry ,01 natural sciences ,Analytical Chemistry ,Arsenic ,Rivers ,Limit of Detection ,Fluorescent Dyes ,Detection limit ,Exonuclease III ,biology ,Chemistry ,Rhodamines ,Drinking Water ,010401 analytical chemistry ,Inverted Repeat Sequences ,Nucleic Acid Hybridization ,DNA ,DNA, Catalytic ,Aptamers, Nucleotide ,Fluoresceins ,Combinatorial chemistry ,Fluorescence ,0104 chemical sciences ,Lakes ,Exodeoxyribonucleases ,Ultrasensitivity ,biology.protein ,Selectivity ,DNA Probes ,Biosensor ,Water Pollutants, Chemical - Abstract
A highly sensitive fluorescence biosensing system was designed for the detection of trace amounts of arsenic(III) (As3+) based on target-triggered successive signal amplification strategy. The specific recognition between the target As3+ and the aptamer sequence results in the release of the blocking DNA to trigger the subsequent signal amplification steps. Exonuclease III (Exo III)-mediated DNA recycling digest process is introduced into the sensing system to generate numerous Mg2+-dependent DNAzymes. After magnetic separation, the active DNAzyme with multiple turnovers could catalyze the continuous cleavage of the fluorophore-quencher-functionalized substrate strands, thus yielding a significantly amplified fluorescence signal for target detection. Due to the synergetic signal amplification of Exo III and DNAzyme, the fluorescent biosensor exhibits ultrasensitivity for As3+ monitoring, with a detection limit of 2 pM. Our established biosensor also displays excellent selectivity toward the target As3+ an...
- Published
- 2019
10. A CRISPR/Cas12a Based Universal Lateral Flow Biosensor for the Sensitive and Specific Detection of African Swine-Fever Viruses in Whole Blood
- Author
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Rong Zeng, Omar Mukama, Jean de Dieu Habimana, Zhiyuan Li, Yinghui Zhang, Chengrong Nie, Wei Wu, Lingwen Zeng, and Jinghua Wu
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Swine ,lcsh:Biotechnology ,target pre-amplification ,Clinical Biochemistry ,detection ,DNA, Single-Stranded ,Biosensing Techniques ,Biology ,Polymerase Chain Reaction ,African swine fever virus ,Fluorescence ,Article ,Virus ,law.invention ,03 medical and health sciences ,chemistry.chemical_compound ,law ,lcsh:TP248.13-248.65 ,Animals ,CRISPR ,Clustered Regularly Interspaced Short Palindromic Repeats ,Polymerase chain reaction ,030304 developmental biology ,Whole blood ,0303 health sciences ,CRISPR–Cas12a ,African swine fever ,030306 microbiology ,General Medicine ,biology.organism_classification ,Virology ,chemistry ,lateral flow biosensor ,CRISPR-Cas Systems ,Biosensor ,DNA - Abstract
Cross-border pathogens such as the African swine fever virus (ASFV) still pose a socio-economic threat. Cheaper, faster, and accurate diagnostics are imperative for healthcare and food safety applications. Currently, the discovery of the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) has paved the way for the diagnostics based on Cas13 and Cas12/14 that exhibit collateral cleavage of target and single-stranded DNA (ssDNA) reporter. The reporter is fluorescently labeled to report the presence of a target. These methods are powerful, however, fluorescence-based approaches require expensive apparatuses, complicate results readout, and exhibit high-fluorescence background. Here, we present a new CRISPR&ndash, Cas-based approach that combines polymerase chain reaction (PCR) amplification, Cas12a, and a probe-based lateral flow biosensor (LFB) for the simultaneous detection of seven types of ASFV. In the presence of ASFVs, the LFB responded to reporter trans-cleavage by naked eyes and achieved a sensitivity of 2.5 ×, 10&minus, 15 M within 2 h, and unambiguously identified ASFV from swine blood. This system uses less time for PCR pre-amplification and requires cheaper devices, thus, it can be applied to virus monitoring and food samples detection.
- Published
- 2020
11. Synergetic performance of isothermal amplification techniques and lateral flow approach for nucleic acid diagnostics
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Yinghui Zhang, Peter Rwibasira, Fanuel Songwe, Xiaogao Meng, Chengrong Nie, Yuan Ting, Samson Mugisha, Omar Mukama, Jean de Dieu Habimana, Lingwen Zeng, and Ammar Al Farga
- Subjects
0303 health sciences ,Materials science ,010401 analytical chemistry ,Biophysics ,Loop-mediated isothermal amplification ,Nanotechnology ,Biosensing Techniques ,Cell Biology ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,03 medical and health sciences ,Nucleic Acids ,Nucleic acid ,Humans ,CRISPR-Cas Systems ,Nucleic Acid Amplification Techniques ,Molecular Biology ,Biosensor ,030304 developmental biology ,Single strand - Abstract
The advancement in developing sensitive, rapid, and specific sensing tools is crucial in diagnostics and biotechnological applications. Although various isothermal amplification approaches exist for the detection and identification of nucleic acids, post-amplicon analysis is still based on traditional methods such as gel electrophoresis, colorimetry, turbidity, which could be non-specific and inconvenient. Thus, this review will first elaborate various isothermal amplification techniques (principle, merits, and demerits) and their potentials when combined with lateral flow approach for point-of-care nucleic acid diagnostics. Different methods for monitoring carryover contamination resulting from amplification product contamination will be discussed. Then, we will present recent advances in diagnostics with both target pre-amplification and CRISPR-Cas systems, which exhibit collateral cleavage of target nucleic acid and a reporter single strand nucleic acid within the vicinity. When the reporter is fluorophore-labeled, it provides a detectable signal by fluorescence or lateral flow biosensors. Lastly, we will discuss how CRISPR-Cas system based diagnostics could be more effective, affordable and portable for on-site detection.
- Published
- 2020
12. A portable and quantitative biosensor for cadmium detection using glucometer as the point-of-use device
- Author
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Lingwen Zeng, Chengshuai Liu, Junhua Chen, Peisen Rong, and Junyu Gong
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Detection limit ,Exonuclease III ,Chromatography ,biology ,Chemistry ,Aptamer ,Glucose meter ,Blood Glucose Self-Monitoring ,010401 analytical chemistry ,Magnetic separation ,02 engineering and technology ,Biosensing Techniques ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Hydrolysis ,Invertase ,Point-of-Care Testing ,biology.protein ,Humans ,0210 nano-technology ,Biosensor ,Cadmium - Abstract
As an ubiquitous heavy metal pollutant, cadmium ion (Cd2+) is detrimental to food and human health even at low concentrations. Conventional methods require costly instruments and cannot meet the requirements of on-site analysis. Here we report the use of a personal glucose meter (PGM) as the point-of-use (POU) device for portable and quantitative detection of Cd2+. The specific recognition between the aptamer and Cd2+ trigger the recycling signal amplification process by exonuclease III (Exo III). After successive hybridization and cleavage reactions, numerous single-stranded DNA were liberated on the surface of the magnetic bead. An invertase-conjugated DNA that is complementary to the single-stranded DNA is introduced into the sensing system. After magnetic separation, the invertase conjugates hydrolyze sucrose into glucose, thus establishing direct conversion of Cd2+ concentration to glucose amount, which can be directly quantified by a PGM. Thanks to the synergistic signal amplification of Exo III and invertase, the POU device greatly improves the sensitivity for Cd2+ analysis, with a detection limit of 5 p.M. With the advantages of portability, cost-effectiveness, wide availability, and ease of use, the PGM-based detector has the potential to be used by the public as a routine tool for reliable and quantitative detection of Cd2+.
- Published
- 2018
13. A wash-free and label-free colorimetric biosensor for naked-eye detection of aflatoxin B1 using G-quadruplex as the signal reporter
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Jinghua Wu, Lingwen Zeng, Junhua Chen, Nianlong Li, and Chengshuai Liu
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Aflatoxin ,Aflatoxin B1 ,Food Contamination ,Biosensing Techniques ,G-quadruplex ,01 natural sciences ,Signal ,Analytical Chemistry ,0404 agricultural biotechnology ,Limit of Detection ,Label free ,Exonuclease III ,biology ,Chemistry ,Hybridization probe ,Benzidines ,010401 analytical chemistry ,food and beverages ,04 agricultural and veterinary sciences ,General Medicine ,Hydrogen Peroxide ,040401 food science ,Combinatorial chemistry ,0104 chemical sciences ,G-Quadruplexes ,Exodeoxyribonucleases ,biology.protein ,Colorimetry ,Naked eye ,DNA Probes ,Biosensor ,Food Analysis ,Food Science - Abstract
A wash-free and label-free colorimetric biosensor for the amplified detection of aflatoxin B1 (AFB1) has been constructed by the integration of an ingenious hairpin DNA probe with exonuclease III (Exo III)-assisted signal amplification. The presence of the AFB1 activates the continuous cleavage reactions by Exo III toward a hairpin probe, resulting in the autonomous accumulation of numerous free G-quadruplex sequences, which can catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) by H2O2 to produce a colorimetric response. The naked-eye biosensor is ultrasensitive, enabling the visual detection of trace amounts of AFB1 as low as 1 pM without instrumentation. The sensor is robust and can work even when challenged with complex sample matrices such as peanut samples. With the advantages of simple operation, wash-free and label-free format, visible and intuitive output, and low cost, the naked-eye based colorimetric biosensor is expected to have potential applications for in-field detection of AFB1.
- Published
- 2018
14. Strand displacement amplification for ultrasensitive detection of human pluripotent stem cells
- Author
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Lingwen Zeng, Xingguo Liang, Shiming Zhao, Wei Wu, Yiping Mao, and Xuewen Lu
- Subjects
Pluripotent Stem Cells ,Stage-Specific Embryonic Antigens ,Cell Culture Techniques ,DNA, Single-Stranded ,Metal Nanoparticles ,Biosensing Techniques ,Sensitivity and Specificity ,Biochemistry ,Regenerative medicine ,Analytical Chemistry ,Humans ,Environmental Chemistry ,Antigens, Tumor-Associated, Carbohydrate ,Induced pluripotent stem cell ,Spectroscopy ,Chemistry ,Multiple displacement amplification ,Equipment Design ,Nucleic acid amplification technique ,Embryonic stem cell ,Molecular biology ,Cell culture ,Gold ,Stem cell ,Antibodies, Immobilized ,Nucleic Acid Amplification Techniques - Abstract
Human pluripotent stem cells (hPSCs), such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), provide a powerful model system for studies of cellular identity and early mammalian development, which hold great promise for regenerative medicine. It is necessary to develop a convenient method to discriminate hPSCs from other cells in clinics and basic research. Herein, a simple and reliable biosensor for stem cell detection was established. In this biosensor system, stage-specific embryonic antigen-3 (SSEA-3) and stage-specific embryonic antigen-4 (SSEA-4) were used to mark human pluripotent stem cells (hPSCs). Antibody specific for SSEA-3 was coated onto magnetic beads for hPSCs enrichment, and antibody specific for SSEA-4 was conjugated with carboxyl-modified tDNA sequence which was used as template for strand displacement amplification (SDA). The amplified single strand DNA (ssDNA) was detected with a lateral flow biosensor (LFB). This biosensor is capable of detecting a minimum of 19 human embryonic stem cells by a strip reader and 100 human embryonic stem cells by the naked eye within 80min. This approach has also shown excellent specificity to distinguish hPSCs from other types of cells, showing that it is promising for specific and handy detection of human pluripotent stem cells.
- Published
- 2015
15. A sensitive lateral flow biosensor for Escherichia coli O157:H7 detection based on aptamer mediated strand displacement amplification
- Author
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Xuewen Lu, Yiping Mao, Zhiyuan Fang, Shiming Zhao, Lingwen Zeng, and Wei Wu
- Subjects
Chemistry ,Aptamer ,Multiple displacement amplification ,Biosensing Techniques ,Aptamers, Nucleotide ,Escherichia coli O157 ,medicine.disease_cause ,Biochemistry ,DNA extraction ,Molecular biology ,Analytical Chemistry ,law.invention ,law ,medicine ,Environmental Chemistry ,Naked eye ,Escherichia coli ,Pathogen ,Biosensor ,Spectroscopy ,Polymerase chain reaction - Abstract
Foodborne diseases caused by pathogens are one of the major problems in food safety. Convenient and sensitive point-of-care rapid diagnostic tests for food-borne pathogens have been a long-felt need of clinicians. Commonly used methods for pathogen detection rely on conventional culture-based tests, antibody-based assays and polymerase chain reaction (PCR)-based techniques. These methods are costly, laborious and time-consuming. Herein, we present a simple and sensitive aptamer based biosensor for rapid detection of Escherichia coli O157:H7 (E. coli O157:H7). In this assay, two different aptamers specific for the outmembrane of E. coli O157:H7 were used. One of the aptamers was used for magnetic bead enrichment, and the other was used as a signal reporter for this pathogen, which was amplified by isothermal strand displacement amplification (SDA) and further detected by a lateral flow biosensor. Only the captured aptamers on cell membrane were amplified, limitations of conventional DNA amplification based method such as false-positive can be largely reduced. The generated signals (red bands on the test zone of a lateral flow strip) can be unambiguously read out by the naked eye. As low as 10 colony forming units (CFU) of E. coli O157:H7 were detected in this study. Without DNA extraction, the reduced handling and simpler equipment requirement render this assay a simple and rapid alternative to conventional methods.
- Published
- 2015
16. A Lateral Flow Biosensor for the Detection of Single Nucleotide Polymorphisms
- Author
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Lingwen, Zeng and Zhuo, Xiao
- Subjects
Immunoconjugates ,Genotype ,Point-of-Care Systems ,Metal Nanoparticles ,Biosensing Techniques ,Gold ,Nucleic Acid Amplification Techniques ,Polymorphism, Single Nucleotide - Abstract
A lateral flow biosensor (LFB) is introduced for the detection of single nucleotide polymorphisms (SNPs). The assay is composed of two steps: circular strand displacement reaction and lateral flow biosensor detection. In step 1, the nucleotide at SNP site is recognized by T4 DNA ligase and the signal is amplified by strand displacement DNA polymerase, which can be accomplished at a constant temperature. In step 2, the reaction product of step 1 is detected by a lateral flow biosensor, which is a rapid and cost effective tool for nuclei acid detection. Comparing with conventional methods, it requires no complicated machines. It is suitable for the use of point of care diagnostics. Therefore, this simple, cost effective, robust, and promising LFB detection method of SNP has great potential for the detection of genetic diseases, personalized medicine, cancer related mutations, and drug-resistant mutations of infectious agents.
- Published
- 2017
17. Colorimetric Detection of Copper(II) Ion Using Click Chemistry and Hemin/G-Quadruplex Horseradish Peroxidase-Mimicking DNAzyme
- Author
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Shiming Zhao, Luxin Yu, Dou Wang, Xiaoling Liang, Lingwen Zeng, Xuerong Xing, Quan Luo, and Chenchen Ge
- Subjects
Sodium ascorbate ,Azides ,Cations, Divalent ,Inorganic chemistry ,Biosensing Techniques ,Horseradish peroxidase ,Analytical Chemistry ,chemistry.chemical_compound ,Limit of Detection ,Humans ,Horseradish Peroxidase ,Aqueous solution ,Base Sequence ,biology ,Drinking Water ,food and beverages ,Substrate (chemistry) ,DNA, Catalytic ,Benzidine ,G-Quadruplexes ,chemistry ,Alkynes ,biology.protein ,Click chemistry ,Hemin ,Click Chemistry ,Colorimetry ,Azide ,Copper - Abstract
G-quadruplex-forming sequence can be formed through a copper(I) ion (Cu(+))-catalyzed click chemistry between azide- and alkyne-modified short G-rich sequences in aqueous solution, eliminating immobilization and washing steps of conventional assays. The source for Cu(+) was generated from the reduction of Cu(2+) with the reductant of sodium ascorbate. In the presence of hemin and K(+), the self-assembly of hemin/G-quadruplex structure has the activity of horseradish peroxidase (HRP), which can catalyze its colorless substrate tetrazmethyl benzidine (TMB) into a colored product. Hence, the concentration of Cu(2+) can be evaluated visually for qualitative analysis according to the color change of the solution, and the optical density (OD) value of the resulting solution at 450 nm was also recorded using a microplate reader for quantitative analysis.
- Published
- 2014
18. An Enhanced Strip Biosensor for Rapid and Sensitive Detection of Histone Methylation
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Chenchen Ge, Zhiyuan Fang, Lingwen Zeng, and Luxin Yu
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biology ,Chemistry ,Oligonucleotide ,Blotting, Western ,Metal Nanoparticles ,Biosensing Techniques ,DNA ,Methylation ,Molecular biology ,Analytical Chemistry ,Histones ,Histone H3 ,Histone ,Colloidal gold ,Histone methylation ,biology.protein ,Humans ,Gold ,Epigenetics ,Enhancer ,Biosensor ,HeLa Cells - Abstract
Histone methylation is a crucial epigenetic modification of chromosomes. In this work, we describe an enhanced strip biosensor using oligonucleotide-functionalized gold nanoparticles as an enhancer probe (AuNP-DNA) for rapid and sensitive detection of histone methylation. In conventional strip biosensor, methylated histone is captured on the test zone through the formation of antibody/methylated histone/antibody-labeled AuNP sandwich structures. Whereas, in the enhanced strip biosensor, the AuNPs in the sandwich structures are dual labeled with an antibody and another oligonucleotide (c-DNA). The sequence of the c-DNA is complementary to the oligonucleotide on the enhancer probe. The enhancer probe, AuNP-DNA, hybridizes with the c-DNA on the dual labeled AuNPs, and the color intensity of the red band on the test zone is then enhanced dramatically. The enhanced strip biosensor has been used for the visual detection of trimethylated lysine 9 of histone H3 (H3K9me3) in 20 ng of histone extract from HeLa cells within 15 min. The detection limit is 10-fold and 15-fold lower than the conventional strip biosensor and Western blot, respectively.
- Published
- 2013
19. A lateral flow biosensor for the detection of human pluripotent stem cells
- Author
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Zhiyuan Fang, Lingwen Zeng, Puchang Lie, Luxin Yu, and Wei Wu
- Subjects
Pluripotent Stem Cells ,Stage-Specific Embryonic Antigens ,Biophysics ,Biosensing Techniques ,Biology ,Sensitivity and Specificity ,Biochemistry ,Antigen ,medicine ,Humans ,Antigens, Tumor-Associated, Carbohydrate ,Induced pluripotent stem cell ,Molecular Biology ,Embryonic Stem Cells ,medicine.diagnostic_test ,Equipment Design ,Cell Biology ,Embryonic stem cell ,Molecular biology ,Cell biology ,Colloidal gold ,Immunoglobulin G ,Immunoassay ,biology.protein ,Nanoparticles ,Gold ,Antibody ,Stem cell ,Antibodies, Immobilized ,Biosensor - Abstract
A lateral flow biosensor based on immunoassay has been developed for the detection of human stem cells for the first time. Antibody specific for a human stem cell surface antigen, SSEA-4, is coated onto gold nanoparticles, whereas antibody against another human pluripotent stem cell surface antigen, SSEA-3, is immobilized on the test zone of the NC membrane. Target cells bind to the antibody coated on the gold nanoparticles to form nanoparticles-stem cell complexes, and the complexes are then captured by another antibody immobilized on the test zone to form a red line for visual detection. This biosensor has been successfully applied to human embryonic stem cells and induced pluripotent stem cells. It is capable of detecting a minimum of 10,000 human embryonic stem cells by the naked eye and 7000 cells with a portable strip reader within 20 min. This approach has also shown excellent specificity to distinguish other types of cells. The biosensor shows great promise for specific and handy detection of human pluripotent stem cells.
- Published
- 2013
20. Enzyme-amplified electronic logic gates based on split/intactaptamers
- Author
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Junhua Chen and Lingwen Zeng
- Subjects
chemistry.chemical_classification ,Chemistry ,Aptamer ,fungi ,Thrombin ,Biomedical Engineering ,Biophysics ,Proteins ,NAND gate ,Nanotechnology ,Biosensing Techniques ,General Medicine ,Aptamers, Nucleotide ,NAND logic ,Small molecule ,humanities ,Adenosine Triphosphate ,Molecular recognition ,Enzyme ,Logic gate ,Electrochemistry ,Humans ,Biological system ,AND gate ,Biotechnology - Abstract
A series of enzyme-amplified electronic logic gates (OR, AND, NOR, and NAND) for one-spot simultaneous monitoring of small molecules and proteins has been constructed at the molecular level. This simple but universal system is based on target-induced self-assembly of split aptamer fragments or target-induced conformational changes of intact aptamers. For the OR and AND logic operations, the split aptamer fragments were used as the molecular recognition components, while for the NOR and NAND logic operations, the intact aptamers were used as the molecular recognition components. Using ATP and thrombin as inputs, the split/intact aptamers as molecular recognition elements, biotin as a tracer, and SA–HR as a reporter molecule, the electronic logic operations can be easily realized by generating amplified current signals as outputs. The logic system is robust and can be applied to human serum samples with excellent selectivity. Importantly, the reversibility of these logic gates makes the electronic system feasible to perform the set–reset function. Our work not only provides a “smart” and flexible logic platform for ATP and thrombin sensing, but also can be expanded for other ligands assay, such as adenosine monophosphate (AMP), theophylline, and cocaine, by rationally splitting their aptamer sequences into two fragments.
- Published
- 2013
21. Lateral flow biosensor for multiplex detection of nitrofuran metabolites based on functionalized magnetic beads
- Author
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Xuewen Lu, Jianghong Dong, Lingwen Zeng, Zhiyuan Fang, and Xiaoling Liang
- Subjects
medicine.drug_class ,Nitrofurans ,Metabolite ,02 engineering and technology ,Biosensing Techniques ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,chemistry.chemical_compound ,Mice ,Limit of Detection ,Phenethylamines ,medicine ,Moiety ,Animals ,Derivatization ,Nitrofuran ,Reagent Strips ,Detection limit ,Chromatography ,Goats ,010401 analytical chemistry ,Antibodies, Monoclonal ,Equipment Design ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Ractopamine ,chemistry ,Reagent ,Magnets ,0210 nano-technology ,Biosensor ,Antibodies, Immobilized - Abstract
The use of potential mutagenic nitrofuran antibiotic in food animal production has been banned world-wide. Common methods for nitrofuran detection involve complex extraction procedures. In the present study, magnetic beads functionalized with antibody against nitrofuran derivative were used as both the extraction and color developing media in lateral flow biosensor. Derivatization reagent carboxybenzaldehyde is firstly modified with ractopamine. After reaction with nitrofuran metabolites, the resultant molecule has two functional groups: the metabolite moiety and the ractopamine moiety. Metabolite moiety is captured by the antibody that is coated on magnetic beads. This duplex is then loaded onto biosensor and ractopamine moiety is further captured by the antibody immobilized on the test zone of nitrocellulose membrane. Without tedious organic reagent-based extraction procedure, this biosensor was capable of visually detecting four metabolites simultaneously with a detection limit of 0.1 μg/L. No cross-reactivity was observed in the presence of 50 μg/L interferential components. Graphical abstract Derivatization of nitrofuran metabolites (AHD, AOZ, SEM, or AMOZ) and LFA detection of the derivative products.
- Published
- 2016
22. Portable and quantitative monitoring of mercury ions using DNA-gated mesoporous silica nanoparticles using a glucometer readout
- Author
-
Liang Xiaoling, Dou Wang, Lin Wang, Zhiyuan Fang, and Lingwen Zeng
- Subjects
Materials science ,Silicon dioxide ,Inorganic chemistry ,Nanoparticle ,chemistry.chemical_element ,Metal Nanoparticles ,02 engineering and technology ,Biosensing Techniques ,010402 general chemistry ,01 natural sciences ,Catalysis ,Ion ,chemistry.chemical_compound ,Materials Chemistry ,Nanotechnology ,Metal nanoparticles ,Ions ,Blood Glucose Self-Monitoring ,Metals and Alloys ,General Chemistry ,DNA ,Mercury ,Mesoporous silica ,021001 nanoscience & nanotechnology ,Silicon Dioxide ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Mercury (element) ,chemistry ,Ceramics and Composites ,Nanoparticles ,0210 nano-technology ,Biosensor ,Nuclear chemistry - Abstract
A novel glucometer biosensor was developed for the quantitative detection of mercury ions (Hg2+) based on glucose-loaded DNA-gated mesoporous silica nanoparticles (MSNs).
- Published
- 2016
23. A lateral flow biosensor for rapid detection of DNA-binding protein c-jun
- Author
-
Chenchen Ge, Lingwen Zeng, Zhiyuan Fang, Puchang Lie, and Wenjuan Zhang
- Subjects
Lysis ,Proto-Oncogene Proteins c-jun ,Biomedical Engineering ,Biophysics ,Metal Nanoparticles ,Biosensing Techniques ,macromolecular substances ,Plasma protein binding ,Chromatography, Affinity ,chemistry.chemical_compound ,Electrochemistry ,Humans ,Chromatography ,Chemistry ,technology, industry, and agriculture ,General Medicine ,Membrane ,Biochemistry ,Colloidal gold ,Gold ,Target protein ,DNA Probes ,Biosensor ,Nitrocellulose ,HeLa Cells ,Biotechnology ,Conjugate - Abstract
A lateral flow biosensor based on an immuno-chromatographic assay has been developed for the detection of DNA-binding proteins. The biosensor is composed of four parts: a sample pad, a conjugate pad, a strip of nitrocellulose membrane and an absorbent pad. A DNA probe containing a specific protein binding consensus sequence is coated onto gold nanoparticles, while an antibody against the DNA-binding protein is immobilized onto a test zone of the nitrocellulose membrane. The target protein binds to the protein binding DNA sequence that is coated on the gold nanoparticles to form nanoparticle-DNA-protein complexes, and the complexes are then captured by the antibody immobilized on the test zone to form a red line for visual detection of the target protein. This biosensor was successfully applied to a DNA-binding protein, c-jun, and the developed biosensor allows for the rapid detection of down to 0.2 footprint unit of c-jun protein within 10 min. This biosensor was verified using HeLa cells and it visually detected c-jun activity in 100 μg of crude cell lysate protein. The antibody against c-jun used in the biosensor can distinguish c-jun from other nonspecific proteins, with high specificity.
- Published
- 2011
24. Aptamer−Nanoparticle Strip Biosensor for Sensitive Detection of Cancer Cells
- Author
-
Joseph A. Phillips, Weihong Tan, Xun Mao, Lingwen Zeng, Guodong Liu, and Hui Xu
- Subjects
Chemistry ,Aptamer ,Cell ,Metal Nanoparticles ,Nanoparticle ,Nanotechnology ,Biosensing Techniques ,Cell Separation ,Aptamers, Nucleotide ,Ligands ,Neoplastic Cells, Circulating ,Sensitivity and Specificity ,Article ,Analytical Chemistry ,medicine.anatomical_structure ,Cell culture ,Colloidal gold ,Cell Line, Tumor ,Cancer cell ,Biophysics ,medicine ,Humans ,Gold ,Biosensor ,Systematic evolution of ligands by exponential enrichment - Abstract
We report an aptamer-nanoparticle strip biosensor (ANSB) for the rapid, specific, sensitive and low-cost detection of circulating cancer cells. Known for their high specificity and affinity, aptamers were first selected from live cells by the cell-SELEX (systematic evolution of ligands by exponential enrichment) process. When next combined with the unique optical properties of gold nanoparticles (Au-NPs), ANSBs were prepared on a lateral flow device. Ramos cells were used as a model target cell to demonstrate proof of principle. Under optimal conditions, the ANSB was capable of detecting a minimum of 4000 Ramos cells without instrumentation (visual judgment) and 800 Ramos cells with a portable strip reader within 15 minutes. Importantly, ANSB has successfully detected Ramos cells in human blood, thus providing a rapid, sensitive and low-cost quantitative tool for the detection of circulating cancer cells. ANSB therefore shows great promise for in-field and point-of-care cancer diagnosis and therapy.
- Published
- 2009
25. Enzyme-free strip biosensor for amplified detection of Pb2+based on a catalytic DNA circuit
- Author
-
Lingwen Zeng, Xuemeng Zhou, and Junhua Chen
- Subjects
Chemistry ,Metals and Alloys ,Analytical chemistry ,Enzyme free ,Biosensing Techniques ,DNA, Catalytic ,General Chemistry ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Visual detection ,Lead ,Biocatalysis ,Materials Chemistry ,Ceramics and Composites ,Biosensor ,DNA - Abstract
A simple and enzyme-free strip biosensor for the amplified detection of Pb(2+) has been constructed based on a catalytic DNA circuit. This assay is ultrasensitive, enabling the visual detection of Pb(2+) concentrations as low as 10 pM without instrumentation.
- Published
- 2013
26. A lateral flow biosensor for detection of nucleic acids with high sensitivity and selectivity
- Author
-
Zhiyuan Fang, Boying Dun, Lingwen Zeng, Puchang Lie, and Jie Liu
- Subjects
Nucleic acid quantitation ,Molecular Sequence Data ,Biosensing Techniques ,Catalysis ,Limit of Detection ,Nucleic Acids ,Materials Chemistry ,Polymerase ,Detection limit ,Chromatography ,Base Sequence ,biology ,Chemistry ,technology, industry, and agriculture ,Metals and Alloys ,Equipment Design ,General Chemistry ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Colloidal gold ,Ceramics and Composites ,biology.protein ,Nucleic acid ,Nanoparticles ,Gold ,Selectivity ,Biosensor ,Sensitivity (electronics) - Abstract
A lateral flow biosensor based on isothermal strand-displacement polymerase reaction and gold nanoparticles has been developed for the visual detection of nucleic acids with a detection limit of 0.01 fM.
- Published
- 2012
27. Lateral flow biosensor for DNA extraction-free detection of Salmonella based on aptamer mediated strand displacement amplification
- Author
-
Wei Wu, Xuewen Lu, Zhiyuan Fang, and Lingwen Zeng
- Subjects
DNA, Bacterial ,Salmonella ,Salmonella enteritidis ,Aptamer ,Point-of-Care Systems ,Molecular Sequence Data ,Biomedical Engineering ,Biophysics ,Biosensing Techniques ,Biology ,medicine.disease_cause ,Rapid detection ,Sensitivity and Specificity ,Electrochemistry ,medicine ,Humans ,Base Sequence ,Multiple displacement amplification ,General Medicine ,Equipment Design ,Aptamers, Nucleotide ,DNA extraction ,Molecular biology ,Magnetic bead ,Salmonella Infections ,Food Microbiology ,Biosensor ,Nucleic Acid Amplification Techniques ,Biotechnology - Abstract
Convenient and sensitive point-of-care rapid diagnostic tests for food-borne pathogens have been a long-felt need of clinicians. Traditional approaches such as culture-based methods have good sensitivity and specificity, but they tend to be tedious and time-consuming. Herein we present a simple and sensitive aptamer based biosensor for rapid detection of Salmonella enteritidis (S. enteritidis). One of the aptamers specific for the outmembrane of S. enteritidis was used for magnetic bead enrichments. Another aptamer against S. enteritidis was used as a reporter for this pathogen, which was amplified by isothermal strand displacement amplification (SDA) and further detected by a lateral flow biosensor. As low as 10(1) colony forming unit (CFU) of S. enteritidis was detected in this study. Without DNA extraction, the reduced handling and simpler equipment requirement render this assay a simple and rapid alternative to conventional methods.
- Published
- 2013
28. Lateral flow biosensors for the detection of nucleic acid
- Author
-
Lingwen, Zeng, Puchang, Lie, Zhiyuan, Fang, and Zhuo, Xiao
- Subjects
DNA, Bacterial ,Base Sequence ,DNA, Viral ,Animals ,Humans ,Metal Nanoparticles ,Biosensing Techniques ,Gold ,Hepacivirus ,Mycobacterium tuberculosis ,DNA Probes ,Nucleic Acid Amplification Techniques - Abstract
The detection of nucleic acid is of central importance for the diagnosis of genetic diseases, infectious agents, and biowarfare agents. Traditional strategies and technologies for nucleic acid detection are time-consuming and labor-intensive. Recently, isothermal strand-displacement reaction-based lateral flow biosensors have attracted a great deal of research interest because they are sensitive, simple, fast, and easy to use. Here, we describe a lateral flow biosensor based on isothermal strand-displacement polymerase reaction and gold nanoparticles for the visual detection of nucleic acid.
- Published
- 2013
29. An enzyme-free and label-free assay for copper(II) ion detection based on self-assembled DNA concatamers and Sybr Green I
- Author
-
Lingbo Chen, Lingwen Zeng, Zhiyuan Fang, Qi Liu, Wei Wu, Xuerong Xing, Junhua Chen, Lin Wang, and Chenchen Ge
- Subjects
inorganic chemicals ,Analytical chemistry ,chemistry.chemical_element ,Enzyme free ,Biosensing Techniques ,Diamines ,Biochemistry ,Analytical Chemistry ,Ion ,Self assembled ,chemistry.chemical_compound ,Electrochemistry ,Environmental Chemistry ,Benzothiazoles ,Organic Chemicals ,Spectroscopy ,Fluorescent Dyes ,Chromatography ,Base Sequence ,DNA ,Fluorescence ,Copper ,Spectrometry, Fluorescence ,chemistry ,SYBR Green I ,Quinolines ,Biosensor - Abstract
An enzyme-free and label-free fluorescence turn on biosensor for amplified copper(II) ion (Cu(2+)) detection has been constructed based on self-assembled DNA concatamers and Sybr Green I. This assay is simple, inexpensive and sensitive, enabling quantitative detection of as low as 12.8 pM Cu(2+).
- Published
- 2013
30. Computational lateral flow biosensor for proteins and small molecules: a new class of strip logic gates
- Author
-
Lingwen Zeng, Zhiyuan Fang, Puchang Lie, and Junhua Chen
- Subjects
Chemistry ,Aptamer ,Thrombin ,Metal Nanoparticles ,Nanotechnology ,STRIPS ,Biosensing Techniques ,Models, Theoretical ,Small molecule ,Analytical Chemistry ,law.invention ,Molecular recognition ,Adenosine Triphosphate ,Flow (mathematics) ,Colloidal gold ,law ,Logic gate ,Humans ,Gold ,Biological system ,Biosensor ,Aptamers, Peptide - Abstract
The first example of strip logic gates ("OR" and "AND" functions) for proteins and small molecules has been constructed on the basis of target-induced self-assembly of split aptamer fragments. Using thrombin and ATP as inputs, the corresponding split/integrated aptamers as molecular recognition elements, and gold nanoparticles as a tracer, the output signals can be directly visualized by observing the red bands on the test zones of the strips. The assay is simple, easy to perform, and cost-effective, allowing portable analysis at ambient temperature. The strip logic system is resistant to nonspecific interfering agents and can operate effectively even in human serum samples. Such logic strips hold great promise for application in intelligent point-of-care and in-field diagnostics.
- Published
- 2012
31. Disposable nucleic acid biosensors based on gold nanoparticle probes and lateral flow strip
- Author
-
Lingwen Zeng, Guodong Liu, Lurong Zhang, Xun Mao, Aiguo Zhang, and Yunqing Ma
- Subjects
Nucleic acid quantitation ,Time Factors ,Molecular Sequence Data ,Analytical chemistry ,Nanoparticle ,Color ,Metal Nanoparticles ,Biosensing Techniques ,Sensitivity and Specificity ,Analytical Chemistry ,Nucleic acid thermodynamics ,Nucleic Acids ,Animals ,Humans ,Disposable Equipment ,Horseradish Peroxidase ,Reagent Strips ,Detection limit ,Base Sequence ,Chemistry ,Genome, Human ,Nucleic Acid Hybridization ,Membrane ,Colloidal gold ,Nucleic acid ,Feasibility Studies ,Cattle ,Gold ,DNA Probes ,Biosensor - Abstract
In this article, we describe a disposable nucleic acid biosensor (DNAB) for low-cost and sensitive detection of nucleic acid samples in 15 min. Combining the unique optical properties of gold nanoparticles (Au-NP) and the high efficiency of chromatographic separation, sandwich-type DNA hybridization reactions were realized on the lateral flow strips, which avoid multiple incubation, separation, and washing steps in the conventional nucleic acid biosensors. The captured Au-NP probes on the test zone and control zone of the biosensor produced the characteristic red bands, enabling visual detection of nucleic acid samples without instrumentation. The quantitative detection was performed by reading the intensities of the produced red bands with a portable strip reader. The parameters (e.g., the concentration of reporter probe, the size of Au-NP, the amount of Au-NP-DNA probe, lateral flow membranes, and the concentration of running buffer) that govern the sensitivity and reproducibility of the sensor were optimized. The response of the optimized device is highly linear over the range of 1-100 nM target DNA, and the limit of detection is estimated to be 0.5 nM in association with a 15 min assay time. The sensitivity of the biosensor was further enhanced by using horseradish peroxidase (HRP)-Au-NP dual labels which ensure a quite low detection limit of 50 pM. The DNAB has been applied for the detection of human genomic DNA directly with a detection limit of 2.5 microg/mL (1.25 fM) by adopting well-designed DNA probes. The new nucleic acid biosensor thus provides a rapid, sensitive, low cost, and quantitative tool for the detection of nucleic acid samples. It shows great promise for in-field and point-of-care diagnosis of genetic diseases and detection of infectious agents or warning against biowarfare agents.
- Published
- 2009
32. A universal biosensor for multiplex DNA detection based on hairpin probe assisted cascade signal amplification
- Author
-
Lingwen Zeng, Boying Dun, Puchang Lie, Jie Liu, and Lingbo Chen
- Subjects
Materials science ,Genotyping Techniques ,Metal Nanoparticles ,Biosensing Techniques ,Computational biology ,Catalysis ,chemistry.chemical_compound ,Limit of Detection ,Materials Chemistry ,Biotinylation ,Multiplex ,Instrumentation (computer programming) ,Detection limit ,Hybridization probe ,Metals and Alloys ,DNA ,Equipment Design ,General Chemistry ,Molecular biology ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry ,Cascade ,Ceramics and Composites ,Gold ,DNA Probes ,Biosensor ,Signal amplification - Abstract
A hairpin DNA probe mediated cascade signal amplification method was developed for visual and rapid DNA analysis with a detection limit of 100 aM. The implementation of tag/anti-tag DNA and gold nanoparticle reporters permits a universal platform for multiplex genotyping without instrumentation.
- Published
- 2013
33. A simple colorimetric detection of DNA methylation
- Author
-
Chenchen Ge, Jie Liu, Lingwen Zeng, Xuewen Lu, Junhua Chen, and Zhiyuan Fang
- Subjects
Adenomatous polyposis coli ,Adenomatous Polyposis Coli Protein ,DNA, Single-Stranded ,Metal Nanoparticles ,Biosensing Techniques ,Conjugated system ,Biochemistry ,Analytical Chemistry ,Absorbance ,chemistry.chemical_compound ,Electrochemistry ,Environmental Chemistry ,Spectroscopy ,Detection limit ,Chromatography ,biology ,Chemistry ,Antibodies, Monoclonal ,DNA Methylation ,Molecular biology ,Microspheres ,CpG site ,DNA methylation ,Magnets ,biology.protein ,Feasibility Studies ,Colorimetry ,CpG Islands ,Adsorption ,Gold ,Cytosine ,DNA - Abstract
In this work, we describe a simple colorimetric method to detect DNA methylation. Adenomatous polyposis coli (APC) with a small CpG region containing methylated cytosine (methylated APC) was synthesized and tested. Methylated APC was first captured and enriched by anti-5-methylcytosine monoclonal antibody conjugated magnetic microspheres (MMPs). Then a probe partly complementary to the APC sequence was added, resulting in the formation of DNA duplexes. The microsphere-captured probe was then released by heat denaturation and added into unmodified gold nanoparticle (AuNP) solution. Colorimetric detection was performed by salt-induced aggregation. The limit of detection is 80 fmol. Semi-quantitative analysis was done with a UV/Vis spectrophotometer by recording the absorbance of AuNP solution at 520 nm. Thus, this method provides a simple, rapid and quantitative tool for DNA methylation detection.
- Published
- 2012
34. A lateral flow biosensor for detection of single nucleotide polymorphism by circular strand displacement reaction
- Author
-
Zhiyuan Fang, Luxin Yu, Zhuo Xiao, Xuemeng Zhou, Lingwen Zeng, Junhua Chen, Chenchen Ge, Puchang Lie, and Jie Liu
- Subjects
Materials science ,DNA Ligases ,Analytical chemistry ,Metal Nanoparticles ,Single-nucleotide polymorphism ,Biosensing Techniques ,Polymorphism, Single Nucleotide ,Catalysis ,Materials Chemistry ,Single displacement reaction ,Detection limit ,chemistry.chemical_classification ,DNA ligase ,Metals and Alloys ,DNA ,General Chemistry ,Nucleic acid amplification technique ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry ,Colloidal gold ,Ceramics and Composites ,Gold ,Nucleic Acid Amplification Techniques ,Biosensor ,Signal amplification - Abstract
A lateral flow biosensor for detection of single nucleotide polymorphism based on circular strand displacement reaction (CSDPR) has been developed. Taking advantage of high fidelity of T4 DNA ligase, signal amplification by CSDPR, and the optical properties of gold nanoparticles, this assay has reached a detection limit of 0.01 fM.
- Published
- 2012
35. Lateral flow nucleic acid biosensor for Cu2+ detection in aqueous solution with high sensitivity and selectivity
- Author
-
Zhuo Xiao, Guodong Liu, Jing Huang, Zhiyuan Fang, Qing Wu, Chuanyan Ouyang, Yixing Wu, Puchang Lie, and Lingwen Zeng
- Subjects
Detection limit ,Aqueous solution ,Chromatography ,Chemistry ,Metals and Alloys ,Analytical chemistry ,Deoxyribozyme ,Metal Nanoparticles ,chemistry.chemical_element ,Biosensing Techniques ,DNA, Catalytic ,General Chemistry ,Copper ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Colloidal gold ,Materials Chemistry ,Ceramics and Composites ,Nucleic acid ,Gold ,Selectivity ,Biosensor - Abstract
A lateral flow nucleic acid biosensor based on copper-dependent DNA-cleaving DNAzyme and gold nanoparticles has been developed for the visual detection of copper ions (Cu(2+)) in an aqueous solution with a detection limit of 10 nM.
- Published
- 2010
36. Molecular beacon-functionalized gold nanoparticles as probes in dry-reagent strip biosensor for DNA analysis
- Author
-
Qingxiang Zeng, Xun Mao, Guodong Liu, Hui Xu, and Lingwen Zeng
- Subjects
Reagent strip ,Chemistry ,Hybridization probe ,technology, industry, and agriculture ,Metals and Alloys ,Metal Nanoparticles ,Nanotechnology ,Biosensing Techniques ,General Chemistry ,Combinatorial chemistry ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Colloidal gold ,Molecular beacon ,Materials Chemistry ,Ceramics and Composites ,Nucleic acid ,Molecule ,Indicators and Reagents ,Gold ,DNA Probes ,Biosensor ,DNA - Abstract
The highly specific molecule recognition properties of molecular beacons (MB) are combined with the unique optical properties of gold nanoparticles (Au-NPs) for the development of a dry-reagent strip-type nucleic acid biosensor (DSNAB) that enables sensitive and low-cost detection of nucleic acid samples within 15 min.
- Published
- 2009
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