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1.
Mikrochim Acta ; 191(6): 322, 2024 05 10.
Article En | MEDLINE | ID: mdl-38730044

The first electrochemical sensor application in the literature is described for the sensitive and selective determination of the selective Janus kinase (JAK)-1 inhibitor abrocitinib (ABR). ABR is approved by the U.S. Food and Drug Administration (FDA) for the treatment of atopic dermatitis. The molecularly imprinted polymer (MIP)-based sensor was designed to incorporate zinc nanoflower (ZnNFs)-graphene oxide (GO) conjugate (ZnNFs@GO), synthesized from the root methanolic extract (RME) of the species Alkanna cappadocica Boiss. et Bal. to improve the porosity and effective surface area of the glassy carbon electrode (GCE). Furthermore, the MIP structure was prepared using ABR as a template molecule, 4-aminobenzoic acid (4-ABA) as a functional monomer, and other additional components. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) were used to characterize the surface and structure of the synthesized nanomaterial and MIP-based surface. Among the electrochemical methods, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were preferred for detailed electrochemical characterization, and differential pulse voltammetry (DPV) was preferred for all other electrochemical measurements using 5.0 mM [Fe(CN)6]3-/4- solution as the redox probe. The MIP-based sensor, which was the result of a detailed optimization phase, gave a linear response in the 1.0 × 10-13 - 1.0 × 10-12 M range in standard solution and serum sample. The obtained limit of detection (LOD) and limit of quantification (LOQ) values and recovery studies demonstrated the sensitivity, accuracy, and applicability of the sensor. Selectivity, the most important feature of the MIP-based sensor, was verified by imprinting factor calculations using ibrutinib, ruxolitinib, tofacitinib, zonisamide, and acetazolamide.


Electrochemical Techniques , Limit of Detection , Molecularly Imprinted Polymers , Zinc , Molecularly Imprinted Polymers/chemistry , Electrochemical Techniques/methods , Electrochemical Techniques/instrumentation , Zinc/chemistry , Graphite/chemistry , Humans , Aminoimidazole Carboxamide/analogs & derivatives , Aminoimidazole Carboxamide/analysis , Aminoimidazole Carboxamide/blood , Aminoimidazole Carboxamide/chemistry , Nanostructures/chemistry , Electrodes
2.
Molecules ; 29(9)2024 Apr 24.
Article En | MEDLINE | ID: mdl-38731427

Dopamine (DA) and uric acid (UA) are essential for many physiological processes in the human body. Abnormal levels of DA and UA can lead to multiple diseases, such as Parkinson's disease and gout. In this work, a three-dimensional reduced graphene oxide-MXene (3D rGO-Ti3C2) composite electrode was prepared using a simple one-step hydrothermal reduction process, which could separate the oxidation potentials of DA and UA, enabling the simultaneous detection of DA and UA. The 3D rGO-Ti3C2 electrode exhibited excellent electrocatalytic activity towards both DA and UA. In 0.01 M PBS solution, the linear range of DA was 0.5-500 µM with a sensitivity of 0.74 µA·µM-1·cm-2 and a detection limit of 0.056 µM (S/N = 3), while the linear range of UA was 0.5-60 µM and 80-450 µM, with sensitivity of 2.96 and 0.81 µA·µM-1·cm-2, respectively, and a detection limit of 0.086 µM (S/N = 3). In 10% fetal bovine serum (FBS) solution, the linear range of DA was 0.5-500 µM with a sensitivity of 0.41 µA·µM-1·cm-2 and a detection limit of 0.091 µM (S/N = 3). The linear range of UA was 2-500 µM with a sensitivity of 0.11 µA·µM-1·cm-2 and a detection limit of 0.6 µM (S/N = 3). The modified electrode exhibited advantages such as high sensitivity, a strong anti-interference capability, and good repeatability. Furthermore, the modified electrode was successfully used for DA measurement in vivo. This could present a simple reliable route for neurotransmitter detection in neuroscience.


Dopamine , Electrochemical Techniques , Electrodes , Graphite , Uric Acid , Graphite/chemistry , Uric Acid/analysis , Uric Acid/blood , Dopamine/analysis , Dopamine/blood , Electrochemical Techniques/methods , Limit of Detection , Oxidation-Reduction , Humans , Titanium/chemistry , Animals
3.
J Nanobiotechnology ; 22(1): 240, 2024 May 12.
Article En | MEDLINE | ID: mdl-38735931

Zinc oxide nanoparticles (ZnO NPs) stand as among the most significant metal oxide nanoparticles in trigger the formation of reactive oxygen species (ROS) and induce apoptosis. Nevertheless, the utilization of ZnO NPs has been limited by the shallowness of short-wavelength light and the constrained production of ROS. To overcome these limitations, a strategy involves achieving a red shift towards the near-infrared (NIR) light spectrum, promoting the separation and restraining the recombination of electron-hole (e--h+) pairs. Herein, the hybrid plasmonic system Au@ZnO (AZ) with graphene quantum dots (GQDs) doping (AZG) nano heterostructures is rationally designed for optimal NIR-driven cancer treatment. Significantly, a multifold increase in ROS generation can be achieved through the following creative initiatives: (i) plasmonic Au nanorods expands the photocatalytic capabilities of AZG into the NIR domain, offering a foundation for NIR-induced ROS generation for clinical utilization; (ii) elaborate design of mesoporous core-shell AZ structures facilitates the redistribution of electron-hole pairs; (iii) the incorporation GQDs in mesoporous structure could efficiently restrain the recombination of the e--h+ pairs; (iv) Modification of hyaluronic acid (HA) can enhance CD44 receptor mediated targeted triple-negative breast cancer (TNBC). In addition, the introduced Au NRs present as catalysts for enhancing photothermal therapy (PTT), effectively inducing apoptosis in tumor cells. The resulting HA-modified AZG (AZGH) exhibits efficient hot electron injection and e--h+ separation, affording unparalleled convenience for ROS production and enabling NIR-induced PDT for the cancer treanment. As a result, our well-designed mesoporous core-shell AZGH hybrid as photosensitizers can exhibit excellent PDT efficacy.


Gold , Graphite , Oxidative Stress , Quantum Dots , Reactive Oxygen Species , Triple Negative Breast Neoplasms , Zinc Oxide , Triple Negative Breast Neoplasms/drug therapy , Reactive Oxygen Species/metabolism , Humans , Oxidative Stress/drug effects , Female , Cell Line, Tumor , Gold/chemistry , Graphite/chemistry , Zinc Oxide/chemistry , Animals , Quantum Dots/chemistry , Mice , Metal Nanoparticles/chemistry , Apoptosis/drug effects , Hyaluronic Acid/chemistry , Electrons
4.
Anal Chim Acta ; 1308: 342647, 2024 Jun 15.
Article En | MEDLINE | ID: mdl-38740456

BACKGROUND: Presently, glyphosate (Gly) is the most extensively used herbicide globally, Nevertheless, its excessive usage has increased its accumulation in off-target locations, and aroused concerns for food and environmental safety. Commonly used detection methods, such as high-performance liquid chromatography and gas chromatography, have limitations due to expensive instruments, complex pre-processing steps, and inadequate sensitivity. Therefore, a facile, sensitive, and reliable Gly detection method should be developed. RESULTS: A photoelectrochemical (PEC) sensor consisting of a three-dimensional polymer phenylethnylcopper/nitrogen-doped graphene aerogel (PPhECu/3DNGA) electrode coupled with Fe3O4 NPs nanozyme was constructed for sensitive detection of Gly. The microscopic 3D network of electrodes offered fast transfer routes for photo-generated electrons and a large surface area for nanozyme loading, allowing high signal output and analytical sensitivity. Furthermore, the use of peroxidase-mimicking Fe3O4 NPs instead of natural enzyme improved the stability of the sensor against ambient temperature changes. Based on the inhibitory effect of Gly on the catalytic activity Fe3O4 NPs, the protocol achieved Gly detection in the range of 5 × 10-10 to 1 × 10-4 mol L-1. Additionally, feasibility of the detection was confirmed in real agricultural matrix including tea, maize seedlings, maize seeds and soil. SIGNIFICANCE: This work achieved facile, sensitive and reliable analysis towards Gly, and it was expected to inspire the design and utilization of 3D architectures in monitoring agricultural chemicals in food and environmental matrix.


Electrochemical Techniques , Electrodes , Glycine , Glyphosate , Graphite , Nitrogen , Photochemical Processes , Graphite/chemistry , Glycine/analogs & derivatives , Glycine/chemistry , Glycine/analysis , Nitrogen/chemistry , Polymers/chemistry , Copper/chemistry , Gels/chemistry , Herbicides/analysis , Limit of Detection , Magnetite Nanoparticles/chemistry , Magnetic Iron Oxide Nanoparticles/chemistry
5.
ACS Appl Mater Interfaces ; 16(19): 25169-25180, 2024 May 15.
Article En | MEDLINE | ID: mdl-38695741

Additive manufacturing holds promise for rapid prototyping and low-cost production of biosensors for diverse pathogens. Among additive manufacturing methods, screen printing is particularly desirable for high-throughput production of sensing platforms. However, this technique needs to be combined with carefully formulated inks, rapid postprocessing, and selective functionalization to meet all requirements for high-performance biosensing applications. Here, we present screen-printed graphene electrodes that are processed with thermal annealing to achieve high surface area and electrical conductivity for sensitive biodetection via electrochemical impedance spectroscopy. As a proof-of-concept, this biosensing platform is utilized for electrochemical detection of SARS-CoV-2. To ensure reliable specificity in the presence of multiple variants, biolayer interferometry (BLI) is used as a label-free and dynamic screening method to identify optimal antibodies for concurrent affinity to the Spike S1 proteins of Delta, Omicron, and Wild Type SARS-CoV-2 variants while maintaining low affinity to competing pathogens such as Influenza H1N1. The BLI-identified antibodies are robustly bound to the graphene electrode surface via oxygen moieties that are introduced during the thermal annealing process. The resulting electrochemical immunosensors achieve superior metrics including rapid detection (55 s readout following 15 min of incubation), low limits of detection (approaching 500 ag/mL for the Omicron variant), and high selectivity toward multiple variants. Importantly, the sensors perform well on clinical saliva samples detecting as few as 103 copies/mL of SARS-CoV-2 Omicron, following CDC protocols. The combination of the screen-printed graphene sensing platform and effective antibody selection using BLI can be generalized to a wide range of point-of-care immunosensors.


Biosensing Techniques , Graphite , Interferometry , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Graphite/chemistry , SARS-CoV-2/isolation & purification , SARS-CoV-2/immunology , Biosensing Techniques/methods , Humans , Interferometry/instrumentation , Spike Glycoprotein, Coronavirus/immunology , COVID-19/diagnosis , COVID-19/virology , Electrodes , Electrochemical Techniques/methods , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza A Virus, H1N1 Subtype/immunology
6.
J Phys Chem Lett ; 15(19): 5120-5129, 2024 May 16.
Article En | MEDLINE | ID: mdl-38709198

In the past few decades, nanometer-scale pores have been employed as powerful tools for sensing biological molecules. Owing to its unique structure and properties, solid-state nanopores provide interesting opportunities for the development of DNA sequencing technology. Controlling DNA translocation in nanopores is an important means of improving the accuracy of sequencing. Here we present a proof of principle study of accelerating DNA captured across targeted graphene nanopores using surface charge density and find the intrinsic mechanism of the combination of electroosmotic flow induced by charges of nanopore and electrostatic attraction/repulsion between the nanopore and ssDNA. The theoretical study performed here provides a new means for controlling DNA transport dynamics and makes better and cheaper application of graphene in molecular sequencing.


DNA , Graphite , Nanopores , Static Electricity , Graphite/chemistry , DNA/chemistry , DNA, Single-Stranded/chemistry , Electroosmosis , Sequence Analysis, DNA/methods
7.
J Phys Chem B ; 128(19): 4751-4758, 2024 May 16.
Article En | MEDLINE | ID: mdl-38709975

The surface patterning in natural systems has exhibited appreciable functional advantages for life activities, which serve as inspiration for the design of artificial counterparts to achieve functions such as directional liquid transport at the nanoscale. Here, we propose a patterned two-dimensional (2D) in-plane heterostructure with a triangle-shaped hexagonal boron nitride (hBN) track embedded in graphene nanosheets, which can achieve unidirectional and self-propelled transport of nanodroplets carrying various biomolecules such as DNA, RNA, and peptides. Our extensive MD simulations show that the wettability gradient on the patterned heterostructure can drive the motion of nanodroplet with an instantaneous acceleration, which also permits long-distance transport (>100 nm) at the microsecond time scale. The different behaviors of various types of biomolecules have been further studied systematically within the transporting nanodroplets. These findings suggest that these specially designed, patterned heterostructures have the potential for spontaneous, directional transport of important biomolecules, which might be useful in biosensing, drug delivery, and biomedical nanodevices.


Boron Compounds , DNA , Graphite , Molecular Dynamics Simulation , Graphite/chemistry , DNA/chemistry , Boron Compounds/chemistry , Nanostructures/chemistry , RNA/chemistry , Peptides/chemistry , Wettability
8.
Anal Chem ; 96(19): 7772-7779, 2024 May 14.
Article En | MEDLINE | ID: mdl-38698542

There is growing attention focused toward the problems of ecological sustainability and food safety raised from the abuse of herbicides, which underscores the need for the development of a portable and reliable sensor for simple, rapid, and user-friendly on-site analysis of herbicide residues. Herein, a novel multifunctional hydrogel composite is explored to serve as a portable and flexible sensor for the facile and efficient analysis of atrazine (ATZ) residues. The hydrogel electrode is fabricated by doping graphite-phase carbon nitride (g-C3N4) into the aramid nanofiber reinforced poly(vinyl alcohol) hydrogel via a simple solution-casting procedure. Benefiting from the excellent electroactivity and large specific surface area of the solid nanoscale component, the prepared hydrogel sensor is capable of simple, rapid, and sensitive detection of ATZ with a detection limit down to 0.002 ng/mL and per test time less than 1 min. After combination with a smartphone-controlled portable electrochemical analyzer, the flexible sensor exhibited satisfactory analytical performance for the ATZ assay. We further demonstrated the applications of the sensor in the evaluation of the ATZ residues in real water and soil samples as well as the user-friendly on-site point-of-need detection of ATZ residues on various agricultural products. We envision that this flexible and portable sensor will open a new avenue on the development of next-generation analytical tools for herbicide monitoring in the environment and agricultural products.


Atrazine , Electrochemical Techniques , Herbicides , Hydrogels , Atrazine/analysis , Herbicides/analysis , Hydrogels/chemistry , Electrochemical Techniques/instrumentation , Graphite/chemistry , Electrodes , Limit of Detection , Nitriles/chemistry , Nitriles/analysis , Nanofibers/chemistry , Water Pollutants, Chemical/analysis
9.
Sensors (Basel) ; 24(9)2024 May 05.
Article En | MEDLINE | ID: mdl-38733043

In this paper, a novel aptamer-modified nitrogen-doped graphene microelectrode (Apt-Au-N-RGOF) was fabricated and used to specifically identify and detect dopamine (DA). During the synthetic process, gold nanoparticles were loaded onto the active sites of nitrogen-doped graphene fibers. Then, aptamers were modified on the microelectrode depending on Au-S bonds to prepare Apt-Au-N-RGOF. The prepared microelectrode can specifically identify DA, avoiding interference with other molecules and improving its selectivity. Compared with the N-RGOF microelectrode, the Apt-Au-N-RGOF microelectrode exhibited higher sensitivity, a lower detection limit (0.5 µM), and a wider linear range (1~100 µM) and could be applied in electrochemical analysis fields.


Aptamers, Nucleotide , Dopamine , Electrochemical Techniques , Gold , Graphite , Metal Nanoparticles , Microelectrodes , Graphite/chemistry , Dopamine/analysis , Dopamine/chemistry , Aptamers, Nucleotide/chemistry , Gold/chemistry , Electrochemical Techniques/methods , Metal Nanoparticles/chemistry , Biosensing Techniques/methods , Limit of Detection , Nitrogen/chemistry
10.
Int J Nanomedicine ; 19: 3973-3989, 2024.
Article En | MEDLINE | ID: mdl-38711615

Graphene and graphene-based materials have attracted growing interest for potential applications in medicine because of their good biocompatibility, cargo capability and possible surface functionalizations. In parallel, prototypic graphene-based devices have been developed to diagnose, imaging and track tumor growth in cancer patients. There is a growing number of reports on the use of graphene and its functionalized derivatives in the design of innovative drugs delivery systems, photothermal and photodynamic cancer therapy, and as a platform to combine multiple therapies. The aim of this review is to introduce the latest scientific achievements in the field of innovative composite graphene materials as potentially applied in cancer therapy. The "Technology and Innovation Roadmap" published in the Graphene Flagship indicates, that the first anti-cancer drugs using graphene and graphene-derived materials will have appeared on the market by 2030. However, it is necessary to broaden understanding of graphene-based material interactions with cellular metabolism and signaling at the functional level, as well as toxicity. The main aspects of further research should elucidate how treatment methods (e.g., photothermal therapy, photodynamic therapy, combination therapy) and the physicochemical properties of graphene materials influence their ability to modulate autophagy and kill cancer cells. Interestingly, recent scientific reports also prove that graphene nanocomposites modulate cancer cell death by inducing precise autophagy dysfunctions caused by lysosome damage. It turns out as well that developing photothermal oncological treatments, it should be taken into account that near-infrared-II radiation (1000-1500 nm) is a better option than NIR-I (750-1000 nm) because it can penetrate deeper into tissues due to less scattering at longer wavelengths radiation.


Antineoplastic Agents , Graphite , Neoplasms , Graphite/chemistry , Humans , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Neoplasms/drug therapy , Drug Delivery Systems/methods , Photochemotherapy/methods , Autophagy/drug effects , Animals , Nanocomposites/chemistry , Nanocomposites/therapeutic use , Nanomedicine
11.
Int J Mol Sci ; 25(9)2024 Apr 26.
Article En | MEDLINE | ID: mdl-38731956

X-ray fluorescence imaging (XFI) can localize diagnostic or theranostic entities utilizing nanoparticle (NP)-based probes at high resolution in vivo, in vitro, and ex vivo. However, small-animal benchtop XFI systems demonstrating high spatial resolution (variable from sub-millimeter to millimeter range) in vivo are still limited to lighter elements (i.e., atomic number Z≤45). This study investigates the feasibility of focusing hard X-rays from solid-target tubes using ellipsoidal lens systems composed of mosaic graphite crystals with the aim of enabling high-resolution in vivo XFI applications with mid-Z (42≤Z≤64) elements. Monte Carlo simulations are performed to characterize the proposed focusing-optics concept and provide quantitative predictions of the XFI sensitivity, in silico tumor-bearing mice models loaded with palladium (Pd) and barium (Ba) NPs. Based on simulation results, the minimum detectable total mass of PdNPs per scan position is expected to be on the order of a few hundred nanograms under in vivo conform conditions. PdNP masses as low as 150 ng to 50 ng could be detectable with a resolution of 600 µm when imaging abdominal tumor lesions across a range of low-dose (0.8 µGy) to high-dose (8 µGy) exposure scenarios. The proposed focusing-optics concept presents a potential step toward realizing XFI with conventional X-ray tubes for high-resolution applications involving interesting NP formulations.


Graphite , Graphite/chemistry , Animals , Mice , Optical Imaging/methods , Monte Carlo Method , Nanoparticles/chemistry , Palladium/chemistry , Computer Simulation , Spectrometry, X-Ray Emission/methods
13.
Sci Rep ; 14(1): 11535, 2024 May 21.
Article En | MEDLINE | ID: mdl-38773159

In this study, a novel method for the fabrication of hesperidin/reduced graphene oxide nanocomposite (RGOH) with the assistance of gamma rays is reported. The different RGOHs were obtained by varying hesperidin concentrations (25, 50, 100, and 200 wt.%) in graphene oxide (GO) solution. Hesperidin concentrations (25, 50, 100, and 200 wt.%) in graphene oxide (GO) were varied to produce the various RGOHs. Upon irradiation with 80 kGy from γ-Ray, the successful reduction of GO occurred in the presence of hesperidin. The reduction process was confirmed by different characterization techniques such as FTIR, XRD, HRTEM, and Raman Spectroscopy. A cytotoxicity study using the MTT method was performed to evaluate the cytotoxic-anticancer effects of arbitrary RGOH on Wi38, CaCo2, and HepG2 cell lines. The assessment of RGOH's anti-inflammatory activity, including the monitoring of IL-1B and IL-6 activities as well as NF-kB gene expression was done. In addition, the anti-invasive and antimetastatic properties of RGOH, ICAM, and VCAM were assessed. Additionally, the expression of the MMP2-9 gene was quantified. The assessment of apoptotic activity was conducted by the detection of gene expressions related to BCl2 and P53. The documentation of the JNK/SMAD4/MMP2 signaling pathway was ultimately accomplished. The findings of our study indicate that RGOH therapy has significant inhibitory effects on the JNK/SMAD4/MMP2 pathway. This suggests that it could be a potential therapeutic option for cancer.


Gamma Rays , Graphite , Hesperidin , Matrix Metalloproteinase 2 , Nanocomposites , Smad4 Protein , Humans , Graphite/chemistry , Graphite/pharmacology , Nanocomposites/chemistry , Hesperidin/pharmacology , Hesperidin/chemistry , Smad4 Protein/metabolism , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 2/genetics , Green Chemistry Technology/methods , Signal Transduction/drug effects , Caco-2 Cells , Hep G2 Cells , Cell Line, Tumor , MAP Kinase Kinase 4/metabolism
14.
J Nanobiotechnology ; 22(1): 274, 2024 May 22.
Article En | MEDLINE | ID: mdl-38773614

Small extracellular vesicle-derived microRNAs (sEV-miRNAs) have emerged as promising noninvasive biomarkers for early cancer diagnosis. Herein, we developed a molecular probe based on three-dimensional (3D) multiarmed DNA tetrahedral jumpers (mDNA-Js)-assisted DNAzyme activated by Na+, combined with a disposable paper-based electrode modified with a Zr-MOF-rGO-Au NP nanocomplex (ZrGA) to fabricate a novel biosensor for sEV-miRNAs Assay. Zr-MOF tightly wrapped by rGO was prepared via a one-step method, and it effectively aids electron transfer and maximizes the effective reaction area. In addition, the mechanically rigid, and nanoscale-addressable mDNA-Js assembled from the bottom up ensure the distance and orientation between fixed biological probes as well as avoid probe entanglement, considerably improving the efficiency of molecular hybridization. The fabricated bioplatform achieved the sensitive detection of sEV-miR-21 with a detection limit of 34.6 aM and a dynamic range from100 aM to 0.2 µM. In clinical blood sample tests, the proposed bioplatform showed results highly consistent with those of qRT-PCRs and the signal increased proportionally with the NSCLC staging. The proposed biosensor with a portable wireless USB-type analyzer is promising for the fast, easy, low-cost, and highly sensitive detection of various nucleic acids and their mutation derivatives, making it ideal for POC biosensing.


Biosensing Techniques , Extracellular Vesicles , Limit of Detection , Metal-Organic Frameworks , MicroRNAs , Paper , Metal-Organic Frameworks/chemistry , Extracellular Vesicles/chemistry , Humans , Biosensing Techniques/methods , DNA, Catalytic/chemistry , Graphite/chemistry , Gold/chemistry , DNA/chemistry , Metal Nanoparticles/chemistry , Nucleic Acid Hybridization , Electrochemical Techniques/methods , Electrodes , Zirconium/chemistry
15.
J Pharm Biomed Anal ; 245: 116200, 2024 Aug 01.
Article En | MEDLINE | ID: mdl-38723557

A high-performance liquid chromatography (HPLC) method was developed for the analysis of Allopurinol and its Ph.Eur. impurities using a porous graphitic carbon (PGC) stationary phase. Retention behavior of solutes was studied across a wide temperature range (30-90 °C) and various gradient times (5-20 min). Analysis of the data revealed distinct retention mechanisms between reversed-phase and PGC phases. However, it was proved that the retention of Allopurinol and its Ph.Eur. impurities on PGC stationary phase can be effectively modeled using the linear solvent strength (LSS) theory. This allows for the utilization of LSS-based method development software to optimize methods under these conditions. By using commercial chromatographic modeling software, separation of Allopurinol and Ph.Eur. impurities was optimized within a large design space. At the optimized operating conditions (pH = 2.0, tG = 6 min, T = 60 °C), all solutes were separated within 6 min with baseline resolution. Comparison between predicted and experimentally measured chromatograms further confirmed the applicability of LSS theory in developing analytical methods for PGC-based HPLC systems. The presented approach offers a general framework for method development on PGC phases.


Allopurinol , Graphite , Solvents , Chromatography, High Pressure Liquid/methods , Graphite/chemistry , Solvents/chemistry , Allopurinol/chemistry , Allopurinol/analysis , Porosity , Temperature , Drug Contamination/prevention & control , Hot Temperature
16.
J Chromatogr A ; 1726: 464977, 2024 Jul 05.
Article En | MEDLINE | ID: mdl-38735117

A magnetic molecularly imprinted polymer (MMIP) adsorbent incorporating amino-functionalized magnetite nanoparticles, nitrogen-doped graphene quantum dots and mesoporous carbon (MIP@MPC@N-GQDs@Fe3O4NH2) was fabricated to extract triazine herbicides from fruit juice. The embedded magnetite nanoparticles simplified the isolation of the adsorbent from the sample solution. The N-GQDs and MPC enhanced adsorption by affinity binding with triazines. The MIP layer provided highly specific recognition sites for the selective adsorption of three target triazines. The extracted triazines were determined by high-performance liquid chromatography (HPLC) coupled with diode-array detection (DAD). The developed method exhibited linearity from 1.5 to 100.0 µg L-1 with a detection limit of 0.5 µg L-1. Recoveries from spiked fruit juice samples were in the range of 80.1- 108.4 %, with a relative standard deviation of less than 6.0 %. The developed MMIP adsorbent demonstrated good selectivity, high extraction efficiency, ease of fabrication and use, and good stability.


Carbon , Fruit and Vegetable Juices , Herbicides , Limit of Detection , Molecularly Imprinted Polymers , Quantum Dots , Triazines , Quantum Dots/chemistry , Triazines/chemistry , Triazines/analysis , Triazines/isolation & purification , Herbicides/analysis , Herbicides/isolation & purification , Herbicides/chemistry , Fruit and Vegetable Juices/analysis , Adsorption , Molecularly Imprinted Polymers/chemistry , Carbon/chemistry , Chromatography, High Pressure Liquid/methods , Magnetite Nanoparticles/chemistry , Solid Phase Microextraction/methods , Molecular Imprinting/methods , Porosity , Graphite/chemistry
17.
ACS Appl Bio Mater ; 7(5): 3215-3226, 2024 May 20.
Article En | MEDLINE | ID: mdl-38695746

This study presents a tetra-substituted phthalonitrile derivative, namely, diethyl 2-(3,4-dicyano-2,5-bis(hexyloxy)-6-(4-(trifluoromethoxy)phenoxy)phenyl)malonate (a), cyclotetramerizing in the presence of some metal salts. The resultant hexadeca-substituted metal phthalocyanines [M= Co, Zn, InCl)] (b-d) were used for the modification of reduced graphene oxide for the first time. The effect of the phthalonitrile/metal phthalocyanines on biological features of reduced graphene oxide (rGO) was extensively examined by the investigation of antioxidant, antimicrobial, DNA cleavage, cell viability, and antibiofilm activities of nanobioagents (1-4). The results were compared with those of unmodified rGO (nanobioagent 5), as well. Modification of reduced graphene oxide with the synthesized compounds improved its antioxidant activity. The antioxidant activities of all the tested nanobioagents also enhanced as the concentration increased. The antibacterial activities of all the nanobioagents improved by applying the photodynamic therapeutic (PDT) method. All the phthalonitrile/phthalocyanine-based nanobioagents (especially phthalocyanine-based nanocomposites) exhibited DNA cleavage activities, and complete DNA fragmentation was observed for nanobioagents (1-4) at 200 mg/L. They can be used as potent antimicrobial and antimicrobial photodynamic therapy agents as well as Escherichia coli microbial cell inhibitors. As a result, the prepared nanocomposites can be considered promising candidates for biomedicine.


Anti-Bacterial Agents , Biocompatible Materials , Graphite , Indoles , Isoindoles , Materials Testing , Particle Size , Graphite/chemistry , Graphite/pharmacology , Indoles/chemistry , Indoles/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Biocompatible Materials/chemical synthesis , Microbial Sensitivity Tests , Cell Survival/drug effects , Escherichia coli/drug effects , Molecular Structure , Biofilms/drug effects , Humans , Antioxidants/pharmacology , Antioxidants/chemistry , Antioxidants/chemical synthesis , Oxides/chemistry , Oxides/pharmacology
18.
Biosens Bioelectron ; 258: 116315, 2024 Aug 15.
Article En | MEDLINE | ID: mdl-38701536

Research in electrochemical detection in lateral flow assays (LFAs) has gained significant momentum in recent years. The primary impetus for this surge in interest is the pursuit of achieving lower limits of detection, especially given that LFAs are the most widely employed point-of-care biosensors. Conventionally, the strategy for merging electrochemistry and LFAs has centered on the superposition of screen-printed electrodes onto nitrocellulose substrates during LFA fabrication. Nevertheless, this approach poses substantial limitations regarding scalability. In response, we have developed a novel method for the complete integration of reduced graphene oxide (rGO) electrodes into LFA strips. We employed a CO2 laser to concurrently reduce graphene oxide and pattern nitrocellulose, exposing its backing to create connection sites impervious to sample leakage. Subsequently, rGO and nitrocellulose were juxtaposed and introduced into a roll-to-roll system using a wax printer. The exerted pressure facilitated the transfer of rGO onto the nitrocellulose. We systematically evaluated several electrochemical strategies to harness the synergy between rGO and LFAs. While certain challenges persist, our rGO transfer technology presents compelling potential for setting a new standard in electrochemical LFA fabrication.


Biosensing Techniques , Electrochemical Techniques , Electrodes , Graphite , Point-of-Care Systems , Graphite/chemistry , Biosensing Techniques/instrumentation , Biosensing Techniques/methods , Electrochemical Techniques/methods , Electrochemical Techniques/instrumentation , Humans , Equipment Design , Collodion/chemistry , Point-of-Care Testing , Limit of Detection , Oxidation-Reduction
19.
ACS Appl Bio Mater ; 7(5): 3358-3374, 2024 May 20.
Article En | MEDLINE | ID: mdl-38717870

Exosomes are promising nanocarriers for drug delivery. Yet, it is challenging to apply exosomes in clinical use due to the limited understanding of their physiological functions. While cellular uptake of exosomes is generally known through endocytosis and/or membrane fusion, the mechanisms of origin-dependent cellular uptake and subsequent cargo release of exosomes into recipient cells are still unclear. Herein, we investigated the intricate mechanisms of exosome entry into recipient cells and intracellular cargo release. In this study, we utilized chiral graphene quantum dots (GQDs) as representatives of exosomal cargo, taking advantage of the superior permeability of chiral GQDs into lipid membranes as well as their excellent optical properties for tracking analysis. We observed that the preferential cellular uptake of exosomes derived from the same cell-of-origin (intraspecies exosomes) is higher than that of exosomes derived from different cell-of-origin (cross-species exosomes). This uptake enhancement was attributed to receptor-ligand interaction-mediated endocytosis, as we identified the expression of specific ligands on exosomes that favorably interact with their parental cells and confirmed the higher lysosomal entrapment of intraspecies exosomes (intraspecies endocytic uptake). On the other hand, we found that the uptake of cross-species exosomes primarily occurred through membrane fusion, followed by direct cargo release into the cytosol (cross-species direct fusion uptake). We revealed the underlying mechanisms involved in the cellular uptake and subsequent cargo release of exosomes depending on their cell-of-origin and recipient cell types. Overall, this study envisions valuable insights into further advancements in effective drug delivery using exosomes, as well as a comprehensive understanding of cellular communication, including disease pathogenesis.


Exosomes , Quantum Dots , Quantum Dots/chemistry , Exosomes/metabolism , Exosomes/chemistry , Humans , Biocompatible Materials/chemistry , Biocompatible Materials/metabolism , Biocompatible Materials/pharmacology , Fluorescent Dyes/chemistry , Particle Size , Materials Testing , Endocytosis , Graphite/chemistry
20.
Biosens Bioelectron ; 258: 116354, 2024 Aug 15.
Article En | MEDLINE | ID: mdl-38723331

Real-time monitoring of biological markers in sweat is a valuable tool for health assessment. In this study, we have developed an innovative wearable biosensor for precise analysis of glucose in sweat during physical activities. The sensor is based on a single-atom catalyst of platinum (Pt) uniformly dispersed on tricobalt tetroxide (Co3O4) nanorods and reduced graphene oxide (rGO), featuring a unique three-dimensional nanostructure and excellent glucose electrocatalytic performance with a wide detection range of 1-800 µM. Additionally, density functional theory calculations have revealed the synergetic role of Pt active sites in the Pt single-atom catalyst (Co3O4/rGO/Pt) in glucose adsorption and electron transfer, thereby enhancing sensor performance. To enable application in wearable devices, we designed an S-shaped microfluidic chip and a point-of-care testing (POCT) device, both of which were validated for effectiveness through actual use by volunteers. This research provides valuable insights and innovative approaches for analyzing sweat glucose using wearable devices, contributing to the advancement of personalized healthcare.


Biosensing Techniques , Glucose , Graphite , Platinum , Sweat , Wearable Electronic Devices , Biosensing Techniques/instrumentation , Sweat/chemistry , Platinum/chemistry , Humans , Catalysis , Glucose/analysis , Graphite/chemistry , Electrochemical Techniques/instrumentation , Nanotubes/chemistry , Limit of Detection , Equipment Design , Oxides/chemistry
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