Construction of a portable and sensitive electrochemical immunosensor for the rapid detection of erythromycin based on semiconductive bimetallic MOF.

The sensitive determination of antibiotics in food products is vital for ensuring food safety and protecting human health. Herein, we have fabricated a novel electrochemical portable and sensitive electrochemical immunosensor for the efficient detection of erythromycin (ERY) containing in food stuffs. For this, a semiconductive cooper/ferric bimetallic metal-organic framework (scMOF), which was synthesized using 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) as linking ligand (denoted as CuFe(HHTP)), was utilized simultaneously as the platform for anchoring antibody and for modifying the sprinted printed electrode (SPE) to construct the electrochemical immunosensor.

Portable smartphone-assisted amperometric immunosensor based on CoCe-layered double hydroxide for rapidly immunosensing erythromycin.

Herein, we have manufactured a newly designed bifunctional impedimetric and amperometric immunosensor for rapidly detecting erythromycin (ERY) in complicated environments and food stuffs. For this, bimetallic cobalt/cerium-layered double hydroxide nanosheets (CoCe-LDH NSs), which was derived from Co-based zeolite imidazole framework via the structure conversion, was simultaneously utilized as the bioplatform for anchoring the ERY-targeted antibody and for modifying the gold and screen printed electrode. Basic characterizations revealed that CoCe-LDH NSs was composed of mixed metal valences, enrich redox, and abundant oxygen vacancies, facilitating the adhesion on the electrode, the antibody adsorption, and the electron transfers.

Schottky Junction Nanozyme Based on Mn-Bridged Co-Phthalocyanines and TiCT Nanosheets Boosts Integrative Type I and II Photosensitization for Multimodal Cancer Therapy.

Cancer phototheranostics have the potential for significantly improving the therapeutic effectiveness, as it can accurately diagnose and treat cancer. However, the current phototheranostic platforms leave much to be desired and are often limited by tumor hypoxia. Herein, a Schottky junction nanozyme has been established between a manganese-bridged cobalt-phthalocyanines complex and TiCT MXene nanosheets (CoPc-Mn/TiCT), which can serve as an integrative type I and II photosensitizer for enhancing cancer therapeutic efficacy a photoacoustic imaging-guided multimodal chemodynamic/photothermal/photodynamic therapy strategy under near-infrared (808 nm) light irradiation.

Electrochemical aptasensing strategy based on a multivariate polymertitanium-metal-organic framework for zearalenone analysis.

An electrochemical aptasensing strategy was developed with a novel bioplatform based on a multivariate titanium metal-organic framework, i.e. MTV polyMOF(Ti), to detect zearalenone (ZEN).

Surface plasmon resonance aptasensor based on niobium carbide MXene quantum dots for nucleocapsid of SARS-CoV-2 detection.

A novel label-free surface plasmon resonance (SPR) aptasensor has been constructed for the detection of N-gene of SARS-CoV-2 by using thiol-modified niobium carbide MXene quantum dots (NbC-SH QDs) as the bioplatform for anchoring N-gene-targeted aptamer. In the presence of SARS-CoV-2 N-gene, the immobilized aptamer strands changed their conformation to specifically bind with N-gene. It thus increased the contact area or enlarged the distance between aptamer and the SPR chip, resulting in a change of the SPR signal irradiated by the laser (He-Ne) with the wavelength (λ) of 633 nm.

Ruthenium(II) 1,4,7-trithiacyclononane complexes of curcumin and bisdemethoxycurcumin: Synthesis, characterization, and biological activity.

Two cationic ruthenium(II) 1,4,7-trithiacyclononane ([9]aneS) complexes of curcumin (curcH) and bisdemethoxycurcumin (bdcurcH), namely [Ru(curc)(dmso-S)([9]aneS)]Cl (1) and [Ru(bdcurc)(dmso-S)([9]aneS)]Cl (2) were prepared from the [RuCl(dmso-S)([9]-aneS)] precursor and structurally characterized, both in solution and in the solid state by X-ray crystallography. The corresponding PTA complexes [Ru(curc)(PTA)([9]aneS)]Cl (3) and [Ru(bdcurc)(PTA)([9]aneS)]Cl (4) have been also synthesized and characterized (PTA = 1,3,5-triaza-7-phosphaadamantane). Bioinorganic studies relying on mass spectrometry were performed on complexes 1-4 to assess their interactions with the model protein lysozyme.

Semiconducting CuNi(hexahydroxytriphenylene) framework for electrochemical aptasensing of C6 glioma cells and epidermal growth factor receptor.

A 2D CuNi metal-organic framework (MOF) named CuxNi3-x(HHTP)2 was synthesized with 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) as the linker and was used as a sensitive scaffold to adsorb aptamer strands for the electrochemical detection of living C6 glioma cells and one of their biomarkers, epidermal growth factor receptor (EGFR). Different from conventional MOFs, the CuxNi3-x(HHTP)2 MOF comprises long-range delocalized electrons, a graphene-analog nanostructure, multiple metal states (Cu0/Cu+/Cu2+ and Ni2+/Ni3+), and abundant oxygen vacancies. With these features, the CuxNi3-x(HHTP)2 MOF anchored a large amount of C6 cell-targeted aptamer strands via coordination among metal centers, oligonucleotides, π-π stacking, and van der Waals force.

A multiple aptasensor for ultrasensitive detection of miRNAs by using covalent-organic framework nanowire as platform and shell-encoded gold nanoparticles as signal labels.

We report herein a novel multiple electrochemical aptasensor based on covalent-organic framework (COF) for sensitive and simultaneous detection of miRNA 155 and miRNA 122, by using shell-encoded gold nanoparticles (Au NPs) as signal labels (AgNCs@AuNPs and CuO@AuNPs, respectively, NCs = nanoclusters). A new COF nanowire was synthesized via condensation polymerization of 1,3,6,8-tetra(4-carboxylphenyl)pyrene and melamine (represented by TBAPy-MA-COF-COOH) for multiple aptasensor fabrication. The nanowire was then used as a platform for anchoring single-strand DNA (ssDNA), which was hybridized with the complementary aptamer (cApt) probes of miRNA 155 and miRNA 122.

Bimetallic cerium/copper organic framework-derived cerium and copper oxides embedded by mesoporous carbon: Label-free aptasensor for ultrasensitive tobramycin detection.

We reported a novel bimetallic cerium/copper-based metal organic framework (Ce/Cu-MOF) and its derivatives pyrolyzed at different temperatures, followed by exploiting them as the scaffold of electrochemical aptamer sensors for extremely sensitive detection of trace tobramycin (TOB) in human serum and milk. After the calcination at high temperature, the meal coordination centers (Ce and Cu) were transferred to metal oxides containing various chemical valences, such as Ce(III), Ce(IV), Cu(II) and Cu(0), which were embedded within the mesoporous carbon network originated from the organic ligands (represented by CeO/CuO@mC). Owning to the strong synergistic effect among the metal oxides, mesoporous carbon, and small cavities and open channels of MOF, the as-prepared CeO/CuO@mC nanocomposites not only possess good electrochemical activity but also exhibit strong bioaffinity toward the aptamer strands.

Bifunctional aptasensor based on novel two-dimensional nanocomposite of MoS quantum dots and g-CN nanosheets decorated with chitosan-stabilized Au nanoparticles for selectively detecting prostate specific antigen.

A novel nanostructured biosensing platform was designed based on two-dimensional (2D) nanocomposite of graphitic carbon nitride (g-CN) nanosheets and MoS quantum dots (MoS QDs), followed by decoration with chitosan-stabilized Au nanoparticles (CS-AuNPs) (denoted as MoSQDs@g-CN@CS-AuNPs), of which CS-AuNPs were prepared by plasma enhanced-chemical vapor deposition. Owning to the good surface plasmon performance of the CS-AuNPs and excellent electrochemical activity of MoSQDs@g-CN nanosheets, the as-obtained 2D MoSQDs@g-CN@CS-AuNPs nanocomposite was simultaneously explored to construct both surface plasmon resonance spectroscopy (SPR) sensor and electrochemical aptasensor. The MoSQDs@g-CN@CS-AuNPs-based aptasensor shows strong bio-binding affinity toward the prostate specific antigen (PSA) targeted aptamer strands as compared to the individual component, including MoS QDs, g-CN, and CS-AuNPs.

Aptamer-Embedded Zirconium-Based Metal-Organic Framework Composites Prepared by De Novo Bio-Inspired Approach with Enhanced Biosensing for Detecting Trace Analytes.

A series of Zr-based metal-organic framework (MOF) composites embedded with three kinds of aptamer strands (509-MOF@Apt) were achieved by a one-step de novo synthetic approach. A platform for ultrasensitive detection of analytes, namely, thrombin, kanamycin, and carcinoembryonic antigen (CEA), was also established. Considering the conformational changes caused by the binding interactions between aptamer strands and targeted molecules, the label-free electrochemical aptasensors based on 509-MOF@Apt composites could be developed to detect various target molecules.

Pore modulation of zirconium-organic frameworks for high-efficiency detection of trace proteins.

Tunable electrochemical biosensors based on analogous Zr-MOFs were developed for protein detection, the performances of which rely on the pore sizes and surroundings of the MOFs that show diverse binding behaviors to aptamers and then the targeted proteins. The optimized Zr-MOF-based sensor has high selectivity to lysozyme in a wide concentration range and a low detection limit of 3.6 pg mL, with good repeatability, stability, and applicability in real samples.