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1.
Biosens Bioelectron ; 266: 116736, 2024 Dec 15.
Article in English | MEDLINE | ID: mdl-39226751

ABSTRACT

In photoelectrochemical (PEC) sensors, traditional detection modes such as "signal-on", "signal-off", and "polarity-switchable" limit target signals to a single polarity range, necessitating novel design strategies to enhance the operational scope. To overcome this limitation, we propose, for the first time, a "polarity-transcendent" design concept that enables a continuous response across the polarity spectrum, significantly broadening the sensor's concentration detection range. This concept is exemplified in our new "background-enhanced signal-off polarity-switchable" (BESOPS) mode, where the model analyte let-7a activates a cascade shearing reaction of a DNAzyme walker in conjunction with CRISPR/Cas12a, quantitatively peeling off Cu2O-H2 strands at the Cu2O/TiO2 electrode interface to expose the TiO2 surface. This exposure generates an anodic photocurrent at the expense of the cathodic photocurrent from Cu2O/TiO2, facilitating a seamless transition of the target signal from cathodic to anodic. Through systematic experiments and comparative analyses, the BESOPS sensor demonstrates highly sensitive and precise quantification of let-7a, with a detection limit of 2.5 aM and a broad operating range of 10 aM to 10 nM. Its performance exceeds most reported sensor platforms, highlighting the significant potential of our polarity-transcendent design in expanding the operational range of PEC sensors. This innovative approach paves the way for developing next-generation PEC sensors with enhanced applicability and heightened sensitivity in various critical fields.


Subject(s)
Biosensing Techniques , Copper , Electrochemical Techniques , Limit of Detection , Titanium , Biosensing Techniques/instrumentation , Electrochemical Techniques/methods , Copper/chemistry , Titanium/chemistry , MicroRNAs/analysis , Humans , Equipment Design , CRISPR-Cas Systems , Electrodes
2.
Anal Chem ; 96(37): 14918-14925, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39197157

ABSTRACT

Convenient and accurate quantification of disease-relevant multitargets is essential for community disease screening. However, in the field of photoelectrochemical (PEC) sensors for multisubstance detection, research on the continuous detection of multiple targets using a polarity-switching mode is scarce. In this study, a multiplexed PEC bioassay was developed based on a target-triggered "anodic-cathodic-anodic" multiple-polarity-switchable mode. Employing miRNA-21 and miRNA-141 as model analytes, the photosensitive material combinations of Cu2O/gold nanoparticles (AuNPs)/TiO2 and CdS/AuNPs/TiO2 were successively formed through the specific binding of different whisker branches of Whisker-DNA to Cu2O-H1 and the CdS-tripod DNA ring, respectively. This process reverses the photocurrent polarity from anodic to cathodic and then back to anodic upon detecting different targets, resulting in the high-sensitivity quantification of various biological targets with reduced interference. To enhance the device's utility and affordability in community disease screening, integrating a capacitor and a multimeter-smartphone connection simplifies the assembly and reduces costs. In developing the PEC sensor, the device demonstrated linear detection ranges for miRNA-21 and miRNA-141 from 0.01 fM to 10 nM. Detection limits for miRNA-21 and miRNA-141 were established at 3.2 and 4.3 aM, respectively. The innovative target-triggered multiple-polarity-switchable mode offers adaptability for other multitarget detections by simply modifying the structure of the whisker branches and the combination of photosensitive materials.


Subject(s)
Copper , Electrochemical Techniques , Gold , Metal Nanoparticles , MicroRNAs , Titanium , MicroRNAs/analysis , Gold/chemistry , Metal Nanoparticles/chemistry , Titanium/chemistry , Copper/chemistry , Humans , Cadmium Compounds/chemistry , Sulfides/chemistry , Photochemical Processes , Limit of Detection , DNA/chemistry , DNA/analysis , Biosensing Techniques
3.
Int J Biol Macromol ; 276(Pt 1): 133884, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39013507

ABSTRACT

Based on CRISPR/Cas12a triggered ordered concatemeric DNA probes, a "on/off" self-powered biosensor is developed to achieve highly sensitive detection of thalassemia gene CD142 through open-circuit potential-assisted visual signal output. The ingeniously constructed glucose oxidase (GOD)-functionalized ordered concatemeric DNA probe structure can significantly amplify signal output, while the coupled CRISPR/Cas12a system is served as a "signal switch" with excellent signal-transducing capabilities. When the ordered concatemeric DNA probe structure is anchored on electrode, the response signal of the sensing system is in the "signal on" mode. While, the presence of the target activates the non-specific cleavage activity of the CRISPR/Cas12a system, causing the sensing system to switch to the "signal off" mode. In the detection system, GOD catalyzes the oxidation of glucose to produce hydrogen peroxide, which further catalyzes the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to form a color product, enabling visual signal of the target through naked-eye color contrast. By employing a multifunctional analytical mode combining electrochemical and visual signal outputs, accurate determination of the target is achieved, with linear ranges of 0.0001-100 pM, and detection limits of 48.1 aM (S/N = 3). This work provides a reference method for sensitive detection of thalassemia genes and holds great diagnostic potential in biomedical applications.


Subject(s)
Biosensing Techniques , CRISPR-Cas Systems , DNA Probes , Thalassemia , Humans , Biosensing Techniques/methods , CRISPR-Cas Systems/genetics , DNA Probes/chemistry , DNA Probes/genetics , Thalassemia/diagnosis , Thalassemia/genetics , Glucose Oxidase/chemistry , Glucose Oxidase/metabolism , Electrochemical Techniques/methods , Limit of Detection , Electrodes
4.
Biosens Bioelectron ; 263: 116574, 2024 Nov 01.
Article in English | MEDLINE | ID: mdl-39029276

ABSTRACT

In this work, a platinum-nickel based nanozyme is prepared and used as a coreaction accelerator in the luminol-H2O2 electrochemiluminescence (ECL) system to construct an ECL biosensor for dimethyl phthalate (DMP) detection. The PtNi/NC nanozyme possesses dispersed metal active sites, and the synergistic effect of Pt and Ni endows it with excellent catalytic performance, which effectively converts H2O2 into more superoxide anions, and then significantly enhances the ECL intensity of the luminol system. The ECL mechanism is investigated by combining cyclic voltammetry and ECL with different types of free radical scavengers. Simultaneously, an "off-on" biosensor is constructed by integrating 3D DNA walker with enzyme-free recycling amplification for ultrasensitive detection of DMP. The biosensor based on PtNi/NC nanozyme mediated luminol-H2O2 system and 3D DNA walker exhibits a linear range of 1 × 10-16 to 1 × 10-6 M with a detection limit of 4.3 × 10-17 M (S/N = 3), and displays good stability and specificity. This study demonstrates the advantages of PtNi/NC nanozyme in enhancing the luminol-H2O2 ECL system, providing new strategy for designing efficient ECL emitter and offering a new method for detecting phthalate esters.


Subject(s)
Biosensing Techniques , Electrochemical Techniques , Hydrogen Peroxide , Limit of Detection , Luminescent Measurements , Luminol , Phthalic Acids , Platinum , Biosensing Techniques/methods , Luminol/chemistry , Luminescent Measurements/methods , Electrochemical Techniques/methods , Platinum/chemistry , Hydrogen Peroxide/chemistry , Phthalic Acids/chemistry , Nickel/chemistry , Metal Nanoparticles/chemistry , DNA/chemistry , DNA, Catalytic/chemistry
5.
Anal Chem ; 96(16): 6483-6492, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38613481

ABSTRACT

A disease-targeting nanoplatform that integrates imaging with therapeutic activity would facilitate early diagnosis, treatment, and therapeutic monitoring. To this end, a macrophage membrane-coated Cu-WO3-x-Hydro820 (CWHM) nanoreactor was prepared. This reactor was shown to target inflammatory tissues. The reactive oxygen species (ROS) such as H2O2 and ·OH in inflammatory tissues can react with Hydro820 in the reactor to form the NIR fluorophore IR820. This process allowed photoacoustic/fluorescence dual-mode imaging of H2O2 and ·OH, and it is expected to permit visual diagnosis of inflammatory diseases. The Cu-WO3-x nanoparticles within the nanoreactor shown catalase and superoxide enzyme mimetic activity, allowing the nanoreactor to catalyze the decomposition of H2O2 and ·O2- in inflammatory cells of hepatic tissues in a mouse model of liver injury, thus alleviating the oxidative stress of damaged liver tissue. This nanoreactor illustrates a new strategy for the diagnosis and treatment of hepatitis and inflammatory liver injury.

6.
Int J Biol Macromol ; 264(Pt 2): 130661, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38458292

ABSTRACT

Lung cancer is a major malignant cancer with low survival rates, and early diagnosis is crucial for effective treatment. Herein, a biosensing platform that is self-powered derived from a capacitor-coupled EBFC has been developed for ultra-sensitive real-time identification of microRNA-21 (miRNA-21) with the assistance of a mobile phone. The flexible substrate of the platform is prepared on a carbon paper modified with graphdiyne and gold nanoparticles. The biosensor employs DNAzyme-mediated dual strand displacement amplification, which enhances the signal output intensity of the EBFC and improves selectivity. The coupling of the capacitor with the EBFC significantly amplifies the sensing signal, causing a 10.6-fold surge in current respond and further improving the sensitivity of the sensing platform. The established detection approach demonstrates a linear relationship varied from 0.0001 to 10,000 pM, with a sensitivity down to 32.3 aM as the minimum detectable limit, which has been effectively utilized for detecting miRNA-21 in practical samples. This sensing system provides strong support for the construction of portable detection devices, and the strategy of the platform construction provides an effective method for ultra-sensitive and accurate detection of miRNA, holding great potential in clinical diagnosis, prognosis evaluation, and drug screening for cancer.


Subject(s)
Biosensing Techniques , Lung Neoplasms , Metal Nanoparticles , MicroRNAs , Humans , Lung Neoplasms/diagnosis , Smartphone , Gold , MicroRNAs/genetics , Biosensing Techniques/methods , Biomarkers , Limit of Detection , Electrochemical Techniques
7.
Biosens Bioelectron ; 248: 115962, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38150801

ABSTRACT

Thalassemia is a globally prevalent single-gene blood disorder, with nearly 7% of the world's population being carriers. Therefore, the development of specific and sensitive methods for thalassemia detection holds significant importance. Herein, a sandwich-type electrochemical/colorimetric dual-mode biosensor is developed based on gold nanoparticles (AuNPs)/graphdiyne (GDY) and DNA nanoframeworks for ultra-sensitive detection of CD142 gene associated with sickle cell anemia. Utilizing AuNPs/GDY as the substrate electrode, the fabricated sandwiched DNA nanoframework not only improves selectivity but also introduces numerous signal probes to further amplify the output signal. In the electrochemical mode, glucose oxidase catalyzes the oxidation of glucose, generating electrons that are transferred to the biocathode for a reduction reaction, resulting in an electric signal proportional to the target concentration. In the colorimetric mode, glucose oxidase catalyzes the generation of H2O2 from glucose, and with the aid of horseradish peroxidase, H2O2 oxidizes 3,3',5,5'-tetramethylbenzidine to produce a colored product, enabling colorimetric detection of the target. The dual-mode biosensor demonstrates a detection range of 0.0001-100 pM in the electrochemical mode and a detection range of 0.0001-10,000 pM in the colorimetric mode. The detection limit in the electrochemical mode is determined to be 30.4 aM (S/N=3), while in the colorimetric mode is of 35.6 aM (S/N=3). This dual-mode detection achieves ultra-sensitive detection of CD142, demonstrating broad prospects for application.


Subject(s)
Biosensing Techniques , Graphite , Metal Nanoparticles , Thalassemia , Humans , Gold , Hydrogen Peroxide , Glucose Oxidase , Limit of Detection , Biosensing Techniques/methods , DNA , Glucose , Electrochemical Techniques/methods
8.
Biomacromolecules ; 24(11): 4605-4621, 2023 11 13.
Article in English | MEDLINE | ID: mdl-37917193

ABSTRACT

With the emergence of challenges in the environmental degradation and resource scarcity fields, the research of biobased self-healing polyurethane (BSPU) has become a prevailing trend in the technology of the polyurethane industry and a promising direction for developing biomass resources. Here, the production of BSPU from lignocellulose, vegetable oil, chitosan, collagen, and coumarin is classified, and the principles of designing polyurethane based on compelling examples using the latest methods and current research are summarized. Moreover, the impact of biomass materials on self-healing and mechanical properties, as well as the tailored performance method, are presented in detail. Finally, the applications of BSPU in biomedicine, sensors, coatings, etc. are also summarized, and the possible challenges and development prospects are explored to helpfully make progress in the development of BSPU. These findings demonstrate valuable references and practical significance for future BSPU research.


Subject(s)
Chitosan , Polyurethanes , Biomass
9.
Anal Chim Acta ; 1280: 341876, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37858559

ABSTRACT

Research has shown that microRNAs exhibit regular dysregulation in cancers, making them potential biomarkers for cancer diagnosis. However, achieving specific and sensitive detection of microRNAs has been a challenging task. To address this issue, two-dimensional networked graphdiyne is used to fabricate a self-powered biosensor and establish a new approach for ultra-responsive dual-mode detection of miRNA-141, a breast cancer biomarker. This method detects miRNA-141 using both electrochemical and colorimetric modes by measuring the output electrical signal of an enzyme-based biofuel cell and the RGB blue value of the electrolyte solution. Tetrahedral DNA and DNA nanorods also are immobilized on the electrode as a biocathode and methylene blue is used as the electron acceptor, which is fixed in the DNA phosphate backbone through electrostatic adsorption. The bioanode catalyzes the oxidation of glucose to produce electrons, which reduces methylene blue to its reduced form, resulting in a high open-circuit voltage (EOCV) and a highger RGB Blue value, enabling dual-mode detection. A reliable linear correlation is observed between EOCV values and miRNA-141 concentrations ranging from 0.0001 to 100 pM, with a detection limit of 21.9 aM (S/N = 3). Additionally, the colorimetric mode also demonstrates a reliable linear correlation with a concentration range of 0.0001-10000 pM, and this method can detect a concentration of 22.2 aM (S/N = 3). This innovative research realizes sensitive and accurate determination of miRNA-141 and provides an important new method for cancer diagnosis.


Subject(s)
Biosensing Techniques , Breast Neoplasms , MicroRNAs , Nanotubes , Humans , Female , Biomarkers, Tumor , Breast Neoplasms/diagnosis , Methylene Blue , DNA , Biosensing Techniques/methods , Limit of Detection , Electrochemical Techniques/methods
10.
Anal Chem ; 95(44): 16374-16382, 2023 11 07.
Article in English | MEDLINE | ID: mdl-37871958

ABSTRACT

Based on the controllable instantaneous self-assembly ability of long-chain branched DNA nanostructures and the synergistic effect between nucleic acid amplification without enzymes, a highly sensitive and highly specific self-powered biosensing platform is developed. Two-dimensional graphdiyne is prepared, modified on flexible carbon cloth, and then functionalized with gold nanoparticles. When DNA mi-tubes are applied on it, target thalassemia gene CD122 triggers a dual-catalytic hairpin assembly reaction. The generated nanoscale DNA is precisely captured by the DNA mi-tube, exposing binding sites and activating the hybridization chain reaction to form long-chain branched DNA. Double-stranded DNA, along with dendritic DNA carrying a large number of guanine bases, precisely captures the signal molecule methylene blue (MB), generating a significant electrochemical signal. The redox reaction of MB also causes a proportional change in the system's color, achieving a colorimetric detection functionality. An efficient dual-mode self-powered sensing platform, therefore, is established for detecting the thalassemia gene CD122. The linear response range of target concentration to open-circuit voltage and RGB Blue value is 0.0001-10,000 pM. The detection limit under electrochemical mode is 36.3 aM (S/N = 3), and under colorimetric mode, it is as low as 12.1 aM (S/N = 3). The new method exhibits high sensitivity, excellent selectivity, and high accuracy, providing a universal strategy for designing novel biosensing platforms that can be extended to the detection of other biomolecules.


Subject(s)
Biosensing Techniques , Metal Nanoparticles , Thalassemia , Humans , Gold/chemistry , Eye-Tracking Technology , Biosensing Techniques/methods , Metal Nanoparticles/chemistry , DNA/chemistry , Methylene Blue/chemistry , Limit of Detection , Electrochemical Techniques
11.
Anal Chem ; 95(37): 14052-14060, 2023 09 19.
Article in English | MEDLINE | ID: mdl-37672636

ABSTRACT

One of the highly attractive research directions in the electrochemiluminescence (ECL) field is how to regulate and improve ECL efficiency. Quantum dots (QDs) are highly promising ECL materials due to their adjustable luminescence size and strong luminous efficiency. MoS2 NSs@QDs, an ECL emitter, is synthesized via hydrothermal methods, and its ECL mechanism is investigated using cyclic voltammetry and ECL-potential curves. Then, a stable and vertical attachment of a triplex DNA (tsDNA) probe to the MoS2 nanosheets (NSs) is applied to the electrode. Next, an innovative ECL sensor is courageously empoldered for precise and ultrasensitive detection of target miRNA-199a through the agency of ECL-resonance energy transfer (RET) strategy and a dextrous target-initiated catalytic three-arm DNA junction assembly (CTDJA) based on a toehold strand displacement reaction (TSDR) signal amplification approach. Impressively, the ingenious system not only precisely regulates the distance between energy donor-acceptor pairs leave energy less loss and more ECL-RET efficiency, but also simplifies the operational procedure and verifies the feasibility of this self-assembly process without human intervention. This study can expand MoS2 NSs@QDs utilization in ECL biosensing applications, and the proposed nucleic acid amplification strategy can become a miracle cure for ultrasensitive detecting diverse biomarkers, which helps researchers to better study the tumor mechanism, thereby unambiguously increasing cancer cure rates and reducing the risk of recurrence.


Subject(s)
DNA, Catalytic , MicroRNAs , Humans , Molybdenum , Catalysis , Electrodes
12.
Anal Chim Acta ; 1278: 341713, 2023 Oct 16.
Article in English | MEDLINE | ID: mdl-37709456

ABSTRACT

Thalassemia is one of the most common monogenic diseases, which seriously affects human growth and development, cardiovascular system, liver, etc. There is currently no effective cure for this disease, making screening for thalassemia particularly important. Herein, a self-powered portable device with high sensitivity and specificity for efficiently screening of low-level thalassemia is developed which is enabled with AuNPs/MoS2@C hollow nanorods and triple nucleic acid amplification technologies. It is noteworthy that AuNPs/MoS2@C electrode shows the advantages of high electrocatalytic activity, fast carrier migration rate and large specific surface area, which can significantly improve the stability and output signal of the platform. Using high-efficiency tetrahedral DNA as the probe, the target CD122 gene associated with thalassemia triggers a catalytic hairpin assembly reaction to achieve CD122 recycling while providing binding sites for subsequent hybridization chain reaction, greatly improving the detection accuracy and sensitivity of the device. A reliable electrochemical/colorimetric dual-mode assay for CD122 is then established, with a linear response range of 0.0001-100 pM for target concentration and open circuit voltage, and the detection limit is 78.7 aM (S/N = 3); a linear range of 0.0001-10000 pM for CD122 level and RGB Blue value, with a detection limit as low as 58.5 aM (S/N = 3). This method achieves ultra-sensitive and accurate detection of CD122, providing a new method for the rapid and accurate screening of thalassemia.


Subject(s)
Metal Nanoparticles , Nanotubes , Thalassemia , Humans , Gold , Molybdenum , DNA/genetics , Thalassemia/diagnosis , Thalassemia/genetics
13.
Biosens Bioelectron ; 237: 115557, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37531892

ABSTRACT

MicroRNA-21 (miRNA-21) is currently the only known oncogenic miRNA that is upregulated in almost all malignant tumors and exhibits a broad spectrum of tumor recognition characteristics. It holds significant value in the early diagnosis, malignant degree assessment, and prognostic evaluation of tumors. In this study, a novel dual-mode self-powered sensing platform is developed using Au nanoparticles/graphdiyne as the electrode substrate and combined with DNA nanoring for highly sensitive and specific detection of miRNA-21. The DNA nanoring structure, which is easy to prepare and contains multiple recognition sites, induces significant electrochemical/colorimetric signal responses of the signaling molecule methylene blue. Under optimal conditions, the linear ranges of the electrochemical and colorimetric detection modes of this self-powered sensor are 0.1 fM-100 pM and 0.1 fM-10 nM, respectively, with the detection limits of 35.1 aM and 61.6 aM (S/N=3). This strategy provides a new reference for the sensitive detection of microRNA and has immense potential for application in the screening and detection of clinical nucleic acid diseases.


Subject(s)
Biosensing Techniques , Metal Nanoparticles , MicroRNAs , Biomarkers, Tumor/genetics , Gold/chemistry , Metal Nanoparticles/chemistry , DNA/chemistry , MicroRNAs/genetics , Limit of Detection , Electrochemical Techniques
14.
Mikrochim Acta ; 190(8): 282, 2023 07 06.
Article in English | MEDLINE | ID: mdl-37415021

ABSTRACT

Nanocomposites with multiple functions have attracted much attention in designing novel SERS substrates. In this report, the enrichment ability of MIL-101(Cr) and the local surface plasma resonance (LSPR) of silver nanoparticles are combined to fabricate a SERS substrate denoted as MIL-101-MA@Ag, which can simultaneously produce high-density and uniformly distributed hot spots. Moreover, the enrichment ability of MIL-101(Cr) can further improve the sensitivity by concentrating and transferring the analytes in the vicinity of hot spots. Under optimal conditions, MIL-101-MA@Ag showed good SERS activity for malachite green (MG) and crystal violet (CV), with detection limits as low as 9.5×10-11 M and 9.2×10-12 M at 1616 cm-1, respectively. The prepared substrate has been successfully applied to detect MG and CV in tilapia, the recovery rate of fish tissue extract was 86.4~102%, and the relative standard deviation (RSD) was 8.9~15%. The results demonstrate that MOF-based nanocomposites are expected to be useful SERS substrates and have a universal applicability for the detection of other hazardous molecules.


Subject(s)
Metal Nanoparticles , Nanocomposites , Tilapia , Animals , Gentian Violet , Silver/chemistry , Metal Nanoparticles/chemistry , Spectrum Analysis, Raman/methods , Nanocomposites/chemistry
15.
Anal Chim Acta ; 1271: 341413, 2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37328239

ABSTRACT

Two-dimensional carbon-coated molybdenum disulfide (MoS2@C) hollow nanorods are combined with nucleic acid signal amplification strategies and DNA hexahedral nanoframework to construct a novel self-powered biosensing platform for ultra-sensitive dual-mode detection of tumor suppressor microRNA-199a. The nanomaterial is applied on carbon cloth and then modified with glucose oxidase or using as bioanode. A large number of double helix DNA chains are produced on bicathode by nucleic acid technologies including 3D DNA walker, hybrid chain reaction and DNA hexahedral nanoframework to adsorb methylene blue, producing high EOCV signal. Methylene blue also is reduced and an increased RGB Blue value is observed. For microRNA-199a detection, the assay shows a extensive linear range of 0.0001-100 pM with a low detection limit of 4.94 amol/L (S/N = 3). The method has been applied to the detection of actual serum samples, providing a novel method for the accurate and sensitive detection of tumor markers.


Subject(s)
Biosensing Techniques , Liver Neoplasms , MicroRNAs , Nanotubes , Humans , Molybdenum , Methylene Blue , Biosensing Techniques/methods , DNA , Carbon , Limit of Detection , Electrochemical Techniques/methods
16.
Biosens Bioelectron ; 232: 115310, 2023 Jul 15.
Article in English | MEDLINE | ID: mdl-37087985

ABSTRACT

To achieve sensitive detection of low-content microRNA, photoelectrochemical/electrochromic dual-mode sensor with intrinsically low background signal has been developed, but the two detection modules are usually designed with a series-connected structure, which may cause signal interference and thus affect the detection reliability. To solve the above problems, a decoupled dual-mode bioassay for sensitive miRNA-21 detection with high reliability is constructed in this work, by selecting two capacitors to realize parallel amplification for the two detection modules, supplemented with a 3D DNA nanoring photoelectrode signal amplification strategy. The complete decoupling of the two detection modes, photoelectrochemical and electrochromic, as well as the use of digital multimeter, improves the reliability and accuracy of the sensor, and also frees it from dependence on electrochemical workstation, making detection more intuitive and faster. With simple structure, low cost, good reproducibility, high sensitivity, and easy operation, the capacitor-parallel-amplified decoupled photoelectrochemical/electrochromic dual-mode bioassay has broad application prospect in on-site point-of-care detection of diseases and low-cost clinical diagnosis. The design idea of decoupled dual-mode detector can also be extended to the construction of other dual-mode methods.


Subject(s)
Biosensing Techniques , MicroRNAs , MicroRNAs/genetics , Reproducibility of Results , Biosensing Techniques/methods , Electrochemical Techniques/methods , Nucleic Acid Amplification Techniques/methods , Limit of Detection
17.
Analyst ; 148(6): 1330-1336, 2023 Mar 13.
Article in English | MEDLINE | ID: mdl-36857694

ABSTRACT

Graphdiyne oxide quantum dots (GDYO QDs), as derivatives of graphdiyne (GDY), have excellent electroconductibility and luminous properties and can be applied as a new ECL emitter. Herein, an electrochemiluminescence (ECL) biosensor for miRNA-21 ultrasensitive determination is constructed based on AuNPs/GDY, GDYO QD and oligonucleotide signal amplification strategy that integrates DNA walker and hybridization chain reaction (HCR) amplification. As electrode substrate material, AuNPs/GDY can not only bond with the aptamer CP but can also enhance the conductivity of the interface. When miRNA-21 exists, the DNA walker process is initiated, and the signaling probes are introduced on the electrode surface, producing abundant double-stranded H1/H2; then, H3/H4 undergoes complementary base pairing with H1/H2 through HCR. With the increase in miRNA-21, the 3D DNA nanomachine is actively manipulated, resulting in a gradual increase in ECL signal. This ECL biosensor demonstrates outstanding performance in the determination of miRNA-21 in the linear range from 0.1 fM to 1 nM. This study offers a new sensitive idea for the clinical analysis of cancer biomarkers.


Subject(s)
Biosensing Techniques , Metal Nanoparticles , MicroRNAs , Quantum Dots , MicroRNAs/analysis , Gold , Electrochemical Techniques/methods , Luminescent Measurements/methods , Metal Nanoparticles/chemistry , DNA/genetics , Biosensing Techniques/methods , Quantum Dots/chemistry , Limit of Detection
18.
Analyst ; 148(6): 1362-1370, 2023 Mar 13.
Article in English | MEDLINE | ID: mdl-36857724

ABSTRACT

Exploring new highly efficient electrochemiluminescence (ECL) luminophores is a necessary condition for developing ultrasensitive ECL biosensors. Therefore, a luminescent carbon dot-based covalent organic framework (CD-COF) was prepared using aldehyde-based carbon dots (CDs) and 1,3,5-tris (4-aminophenyl) benzene (TPB). Because the CD-COF made the regular arrangement of CDs conducive to improving the ECL response, CD-COF had a higher ECL intensity and efficiency than CDs. What's more, the ECL intensity of the CD-COF/S2O82-/Bu4N+ system was about 2.98, 7.50, and 28.08 times higher than those of the CD-COF/S2O82-, CDs/S2O82- and S2O82- systems, respectively. Considering the remarkable ECL performance, the CD-COF/S2O82-/Bu4N+ system was employed combined with the CRISPR/Cas12a trans-cutting strategy to construct an "off-on" ECL biosensor for BPA detection. The proposed ECL biosensor exhibited excellent performance with a wide linear range from 1.0 × 10-14 mol L-1 to 1.0 × 10-5 mol L-1 with a low detection limit of 2.21 fM (S/N = 3) under the optimized conditions. The biosensor demonstrated that CD-COF can be used as an efficient ECL emitter, thus expanding the application field of COFs. In addition, the good stability and specificity of the biosensor enabled the rapid detection of BPA, which will provide valuable insights into promising ultrasensitive ECL biosensors.


Subject(s)
Biosensing Techniques , Metal-Organic Frameworks , Carbon , CRISPR-Cas Systems , Luminescent Measurements , Electrochemical Techniques , Limit of Detection
19.
Drug Des Devel Ther ; 17: 717-735, 2023.
Article in English | MEDLINE | ID: mdl-36923105

ABSTRACT

Purpose: To investigate the mechanisms of antidepressant action of active fraction of Polyrhachis vicina Rogers (AFPR) through network pharmacology, molecular docking and experimental validation. Methods: GC-MS was used to predict chemical compounds, corresponding databases were used to predict chemical compound targets and depression targets, Cytoscape software was used to construct and analyze the protein interaction network map, DAVID database was used to analyze gene ontology (GO) and KEGG signaling pathway, and AGFR software was used to perform molecular docking. Subsequently, the underlying action mechanisms of AFPR on depression predicted by network pharmacology analyses were experimentally validated in a CORT-induced depression model in vitro and in vivo. Results: A total of 52 potential targets of AFPR on antidepressant were obtained. GO is mainly related to chemical synaptic transmission, signal transduction and others. KEGG signaling pathways are mainly related to cAMP signaling pathway and C-type lectin receptor signaling pathway. The experiment results showed that AFPR significantly increased the expression of PRKACA, CREB and BDNF in mouse brain tissue and PC12 cells. Furthermore, after interfered of cAMP in PC12 cells, the decreased expression of PRKACA, CREB and BDNF was reversed by AFPR. Conclusion: AFPR may exert antidepressant effects through multiple components, targets and pathways. Furthermore, it could improve neuroplasticity via the cAMP signaling pathway to improve depression-like symptoms.


Subject(s)
Brain-Derived Neurotrophic Factor , Drugs, Chinese Herbal , Rats , Animals , Mice , Molecular Docking Simulation , Depression/drug therapy , Network Pharmacology , Protein Interaction Maps , Medicine, Chinese Traditional
20.
Anal Chim Acta ; 1239: 340696, 2023 Jan 25.
Article in English | MEDLINE | ID: mdl-36628764

ABSTRACT

A highly sensitivity self-powered biosensor is developed based on T7 exonuclease (T7 Exo) and 3D DNA walker induced rolling circle amplification (RCA) for electrochemical/colorimetric dual-mode detection of microRNA-21 (miRNA-21) with improved reliability. Taking its advantage of fascinating properties, such as high structure defects and good conductivity, graphdiyne is prepared and used to prepare high-performance enzyme biofuel cell. T7 Exo-assisted 3D DNA walker target recognition triggers RCA reaction to obtain a significantly amplified signal response. A capacitor is integrated to the enzyme biofuel cell to further amplify the electrochemical output signal of the self-powered biosensor. In detection system, glucose oxidase catalyzes glucose oxidation to produce hydrogen peroxide, and 3,3',5,5'-tetramethylbenzidine (TMB) is then catalyzed to generate colored products, so as to achieve the colorimetric detection of the target. Analysis signals of diverse modes are recorded independently. Consequently, detection of microRNA with improved reliability and wider signal response range are achieved by electrochemical/colorimetric dual-mode with detection limits of 0.15 and 33 fM (S/N = 3) respectively. In addition, the proposed self-powered biosensor successfully applied for the detection of miRNA-21 in human serum samples, confirming its practical applicability in clinical diagnosis. It is powerfully anticipated the proposed self-powered biosensor possesses great potential to be applied to other biomedical domains.


Subject(s)
Biosensing Techniques , MicroRNAs , Humans , MicroRNAs/analysis , Reproducibility of Results , Limit of Detection , DNA/genetics , DNA/analysis , Nucleic Acid Amplification Techniques , Electrochemical Techniques
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