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1.
Anal Chem ; 96(21): 8365-8372, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38717986

RESUMEN

Simultaneous sensitive and precise determination of multibiomarkers is of great significance for improving detection efficiency, reducing diagnosis and treatment expenses, and elevating survival rates. However, the development of simple and portable biosensors for simultaneous determination of multiplexed targets in biological fluids still faces challenges. Herein, a unique and versatile immobilization-free dual-target electrochemical biosensing platform, which combines distinguishable magnetic signal reporters with buoyancy-magnetism separation, was designed and constructed for simultaneous detection of carcinoembryonic (CEA) and α-fetoprotein (AFP) in intricate biological fluids. To construct such distinguishable magnetic signal reporters with signal transduction, amplification, and output, secondary antibodies of CEA and AFP were respectively functionalized on methylene blue (MB) and 6-(ferrocenyl)hexanethiol (FeC) modified Fe3O4@Au magnetic nanocomposites. Meanwhile, a multifunctional flotation probe with dual target recognition, capture, and isolation capability was prepared by conjugating primary antibodies (Ab1-CEA, Ab1-AFP) to hollow buoyant microspheres. The target antigens of CEA and AFP can trigger a flotation-mediated sandwich-type immunoreaction and capture a certain amount of the distinguishable magnetic signal reporter, which enables the conversion of the target CEA and AFP quantities to the signal of the potential-resolved MB and FeC. Thus, the MB and FeC currents of magnetically adsorbed distinguishable magnetic reporters can be used to determine the CEA and AFP targets simultaneously and precisely. Accordingly, the proposed strategy exhibited a delightful linear response for CEA and AFP in the range of 100 fg·mL-1-100 ng·mL-1 with detection limits of 33.34 and 17.02 fg·mL-1 (S/N = 3), respectively. Meanwhile, no significant nonspecific adsorption and cross-talk were observed. The biosensing platform has shown satisfactory performance in the determination of real clinical samples. More importantly, the proposed approach can be conveniently extended to universal detection just by simply substituting biorecognition events. Thus, this work opens up a new promising perspective for dual and even multiple targets and offers promising potential applications in clinical diagnosis.


Asunto(s)
Técnicas Biosensibles , Antígeno Carcinoembrionario , Técnicas Electroquímicas , alfa-Fetoproteínas , alfa-Fetoproteínas/análisis , alfa-Fetoproteínas/inmunología , Antígeno Carcinoembrionario/análisis , Antígeno Carcinoembrionario/inmunología , Técnicas Biosensibles/métodos , Humanos , Inmunoensayo/métodos , Oro/química , Límite de Detección
2.
Talanta ; 274: 126023, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38583328

RESUMEN

Dual-potential ratiometric electrochemiluminescence (ECL) is in favor of resistance to environmental interference. However, two kinds of emitters or coreactants, and a wide scan potential range (>2 V) are mandatory. This work developed a new dual-potential ratiometric ECL sensor for detection of carcinoembryonic antigen (CEA) using single emitter (luminol) and single coreactant (H2O2) with a mild potential range from -0.1 to 0.6 V. Luminol could produce a strong cathodic ECL (Ec) induced by hydroxyl radicals (HO‧) from the reduction of H2O2, and a relatively weak anodic ECL (Ea). After the ferrocene modified CEA aptamer (Apt-Fc) was attached, Fc could promote Ea by catalyzing the oxidation of H2O2, and reduce Ec by consuming HO‧. With the cycling amplification of the exonuclease I, CEA could substantially reduce the amount of Apt-Fc, resulting in the decrease of Ea and the rise of Ec. So, the ratio of Ec to Ea (Ec/Ea) was used as the detection signal, realizing the sensitive determination of CEA from 0.1 pg mL-1 to 10 ng mL-1 with a LOD of 41.85 fg mL-1 (S/N = 3). The developed sensor demonstrated excellent specificity, stability and reproducibility, with satisfactory results in practical detection.


Asunto(s)
Aptámeros de Nucleótidos , Antígeno Carcinoembrionario , Técnicas Electroquímicas , Peróxido de Hidrógeno , Mediciones Luminiscentes , Luminol , Antígeno Carcinoembrionario/análisis , Antígeno Carcinoembrionario/sangre , Técnicas Electroquímicas/métodos , Humanos , Mediciones Luminiscentes/métodos , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/análisis , Luminol/química , Aptámeros de Nucleótidos/química , Límite de Detección , Técnicas Biosensibles/métodos , Metalocenos/química , Compuestos Ferrosos/química
3.
Chem Commun (Camb) ; 59(86): 12911-12914, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37823254

RESUMEN

Compared with single signal detection, a ratiometric biosensor could offer more accurate and reliable results. Here, a ratiometric electrochemical biosensor for the sensitive and accurate detection of dopamine was developed based on the strong adsorption ability of MXene-Au toward methylene blue, an inner reference element. This ratiometric sensing strategy opened up a new avenue for the development of a ratiometric platform.


Asunto(s)
Técnicas Biosensibles , Nanocompuestos , Dopamina , Técnicas Electroquímicas , Técnicas Biosensibles/métodos , Límite de Detección , Oro
4.
Anal Chem ; 95(18): 7336-7343, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37129510

RESUMEN

Rapid and accurate detection of biomolecules is of vital importance for the diagnosis of disease and for performing timely treatments. The point-of-care analysis of cancer biomarkers in the blood with low cost and easy processing is still challenging. Herein, an advanced and robust strategy, which integrates the buoyant recognition probe with the magnetic reporter probe in one solution, was first proposed for immobilization-free electrochemical immunosensing. The tumor marker of alpha fetoprotein (AFP) can be captured immune-buoyantly, and then a multifunctional magnetic reporter probe in pseudo-homogeneous solution was further captured to fulfill a sandwich-type immunoreaction. The residual magnetic reporter probe can be firmly and efficiently attracted on a magnetic glassy carbon electrode to fulfill the conversion of the target AFP amount into the residual magnetic electrochemical signal indicator. As a result, the electrochemical signal of methylene blue can accurately reflect the original level of target antigen AFP concentration. By integrating buoyancy-driven quasi-homogenous biorecognition with magnetism-mediated amplification and signal output, the proposed immobilization-free electrochemical immunosensing strategy displayed a wide range of linear response (100 fg mL-1 to 10 ng mL-1), low detection limit (14.52 fg mL-1), and good reproducibility, selectivity, and stability. The designed strategy manifests remarkable advantages including assay simplicity, rapidness, and high sensitivity owing to the in-solution instead of on-electrode biorecognition that could accelerate and improve the biorecognition efficiency. To the best of our knowledge, this is the first cooperation of buoyancy-driven biorecognition with magnetism-mediated signal output in bioanalysis, which would be attractive for rapid clinic biomedical application. Thus, this work provides a fresh perspective for convenient and favorable immobilization-free electrochemical biosensing of universal biomolecules.


Asunto(s)
Técnicas Biosensibles , alfa-Fetoproteínas , alfa-Fetoproteínas/análisis , Técnicas Electroquímicas , Reproducibilidad de los Resultados , Biomarcadores de Tumor/análisis , Límite de Detección , Inmunoensayo , Oro/química
5.
Biosens Bioelectron ; 226: 115116, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36753989

RESUMEN

DNA nanomachines have shown potential application in the construction of various biosensors. Here, an electrochemiluminescence biosensor for the sensitive detection of miRNA-21 were reported based on three-dimensional (3D) DNA nanomachine and duplex-specific nuclease (DSN)-mediated target recycle amplification strategy. First, the bipedal DNA walkers were obtained by DSN-mediated digestion reaction initiated by target miRNA-21.3D DNA tracks were prepared by modifying Fe3O4 magnetic beads (MBs) with ferrocene-labeled DNA (Fc-DNA). The produced DNA walkers autonomously moved along 3D DNA tracks powered by nicking endonuclease. During the movement, ferrocene-labeled DNA was cleaved, resulting in large amounts of Fc-labeled DNA fragments away from the MBs surface. Finally, the liberated Fc-labeled DNA fragments were dropped on the C-g-C3N4 modified electrode surface, leading to the quenching of C-g-C3N4 electrochemiluminescence (ECL). Benefiting from the dual amplification strategy of 3D DNA nanomachine and DSN-mediated target recycling, the developed ECL biosensor exhibited an excellent performance for miRNA-21 detection with a wide linear range of 10 fM to 10 nM and a low detection limit of 1.0 fM. This work offers a new thought for the application of DNA walkers in the construction of various biosensors.


Asunto(s)
Técnicas Biosensibles , MicroARNs , Metalocenos , Mediciones Luminiscentes/métodos , Endonucleasas , Límite de Detección , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , ADN/genética
6.
Chinese Pharmacological Bulletin ; (12): 731-738, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1013906

RESUMEN

Aim To study the ability of tetramethylpyrazine (TMP) on promoting neurogenesis in neural stem cell microenvironment after oxygen-glucose deprivation (OGD) injury in vitro. Methods Neural stem cells (NSCs), astrocytes (ACs) and cerebral microvascular endothelial cells (BMECs) were respectively extracted and separated to establish a co-culture system. The OGD modeling conditions were optimized by NSCs activity, and the concentration of TMP was optimized by Nissl staining. Then CCK-8 and Nestin

7.
Chinese Journal of Pathology ; (12): 1223-1229, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1012397

RESUMEN

Objective: To explore the application of manual screening collaborated with the Artificial Intelligence TPS-Assisted Cytologic Screening System in urinary exfoliative cytology and its clinical values. Methods: A total of 3 033 urine exfoliated cytology samples were collected at the Henan People's Hospital, Capital Medical University, Beijing, China. Liquid-based thin-layer cytology was prepared. The slides were manually read under the microscope and digitally presented using a scanner. The intelligent identification and analysis were carried out using an artificial intelligence TPS assisted screening system. The Paris Report Classification System of Urinary Exfoliated Cytology 2022 was used as the evaluation standard. Atypical urothelial cells and even higher grade lesions were considered as positive when evaluating the recognition sensitivity, specificity, and diagnostic accuracy of artificial intelligence-assisted screening systems and human-machine collaborative cytologic screening methods in urine exfoliative cytology. Among the collected cases, there were also 1 100 pathological tissue controls. Results: The accuracy, sensitivity and specificity of the AI-assisted cytologic screening system were 77.18%, 90.79% and 69.49%; those of human-machine coordination method were 92.89%, 99.63% and 89.09%, respectively. Compared with the histopathological results, the accuracy, sensitivity and specificity of manual reading were 79.82%, 74.20% and 95.80%, respectively, while those of AI-assisted cytologic screening system were 93.45%, 93.73% and 92.66%, respectively. The accuracy, sensitivity and specificity of human-machine coordination method were 95.36%, 95.21% and 95.80%, respectively. Both cytological and histological controls showed that human-machine coordination review method had higher diagnostic accuracy and sensitivity, and lower false negative rates. Conclusions: The artificial intelligence TPS assisted cytologic screening system has achieved acceptable accuracy in urine exfoliation cytologic screening. The combination of manual screening and artificial intelligence TPS assisted screening system can effectively improve the sensitivity and accuracy of cytologic screening and reduce the risk of misdiagnosis.


Asunto(s)
Humanos , Inteligencia Artificial , Urotelio/patología , Citodiagnóstico , Células Epiteliales/patología , Sensibilidad y Especificidad , Neoplasias Urológicas/orina
8.
Anal Chem ; 94(37): 12845-12851, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36067524

RESUMEN

Ratiometric electrochemiluminescence (ECL) sensors can efficiently remove environmental interference to attain precise detection. Nonetheless, two eligible luminophores or coreactants were usually needed, increasing the complexity and restricting their practical application. In this study, a single luminophore of luminol with a single coreactant of H2O2 was employed to construct a dual-potential ratiometric ECL sensor for the detection of carcinoembryonic antigen (CEA). The produced palladium nanoclusters (Pd NCs) employing a DNA duplex as a template could not only stimulate luminol to produce cathodic ECL (Icathodic) but also quench its anodic ECL (Ianodic). During the detection process, CEA could damage the double-stranded structure and reduce the Pd NCs' amount, triggering a significant decrease in the ratio of Icathodic to Ianodic (Icathodic/Ianodic) and thereby achieving sensitive CEA's detection. Furthermore, the Icathodic/Ianodic was independent of the H2O2 concentration, which avoided a prejudicial effect from H2O2 decomposition and considerably enhanced the detection's reliability. The developed ratiometric ECL sensor demonstrated a sensitive detection toward CEA with a wide linear range from 100 ag/mL to 10 ng/mL and a detection limit of 87.1 ag/mL (S/N = 3). In conclusion, this study offers a new idea for constructing ratiometric ECL sensors based on a single luminophore and technical support for cancer's early diagnosis.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Antígeno Carcinoembrionario , ADN/química , Técnicas Electroquímicas , Peróxido de Hidrógeno , Límite de Detección , Mediciones Luminiscentes , Luminol/química , Nanopartículas del Metal/química , Paladio/química , Reproducibilidad de los Resultados
9.
Food Chem ; 368: 130864, 2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-34438172

RESUMEN

Ultra-high pressure (UHP) is a novel non-thermal pretreatment method in food processing for improving the extraction yield of polyphenols and functional properties. The present work investigated the phenolic profiles, antioxidant activities, and cytoprotective effects of the free, esterified, and insoluble-bound phenolic fractions from mango leaves before and after ultra-high pressure (UHP) treatment. UHPLC-Q-Orbitrap-MS/MS analysis resulted in the identification of 42 phenolic compounds in the different phenolic forms. UHP pretreatment could significantly influence the contents of total phenols, total flavonoids and individual compounds in the different phenolic fractions (p < 0.05). After UHP pretreatment, these phenolic fractions exhibited greater antioxidant activity, and inhibited reactive oxygen species production and cell apoptosis (p < 0.05). Meanwhile, IBP were the most potential antioxidative and cytoprotective ingredients. Therefore, UHP pretreated mango leaves with enhanced bioactivity could be used as biological agents in the health food industry to improve its application and economic values.


Asunto(s)
Antioxidantes , Mangifera , Antioxidantes/farmacología , Cromatografía Líquida de Alta Presión , Flavonoides/análisis , Fenoles/análisis , Extractos Vegetales/farmacología , Hojas de la Planta/química , Espectrometría de Masas en Tándem
10.
Small ; 18(5): e2104524, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34816615

RESUMEN

Structural modulation of core-shell silver nanoclusters from the inside is a huge challenge but of great importance in their syntheses. Herein, two silver nanoclusters [Ag3 S9 @Ag42 ] (SD/Ag45b) and [Ag9 S9 @Ag42 ] (SD/Ag51a) are isolated in the presence of different kinds of sulfonic acids. Uniquely, SD/Ag45b and SD/Ag51a show typical core-shell structures with the similar Ag42 shell but different cores. The outer shell of 42 silver atoms comprises two Ag3 trigons at two poles encircled by three equatorial distorted square cupolas (J4 , Ag12 ). The core in SD/Ag45b is a silver trigon ligated by nine S2- ions (Ag3 S9 ), while a tricapped triangular prismatic Ag9 also ligated by the same amount of S2- ions (Ag9 S9 ) is observed in the inner core of SD/Ag51a. The electrospray ionization mass spectrometry (ESI-MS) indicates that the introduction of p-toluenesulfonic acid can realize the transformation from SD/Ag45b to Ag51 . SD/Ag45b and SD/Ag51a show inverse luminescence thermochromic behaviors in the near-infrared (NIR) region, mainly dictated by the inner silver cores. This work not only realizes the synthesis of new silver nanoclusters by core modulation but also provides a prototype to get molecular-level insight into the correlation between structure and luminescence thermochromism.


Asunto(s)
Luminiscencia , Plata , Plata/química
11.
Acta Anatomica Sinica ; (6): 266-272, 2022.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1015345

RESUMEN

MicroRNAs (miRNAs, miR) are endogenous non-coding single-stranded RNAs with a length of about 22 nucleotides. These RNAs play an important biological function within cells, among which, miR-429 has been proved to play an important role in inhibiting tumor development and tumor progression as well as in cell differentiation and neurological diseases by regulating the expression of different target genes. In this paper, the role of miR-429 and its downstream targeted genes in cell proliferation, apoptosis, migration and invasion is summarized.

12.
Mikrochim Acta ; 189(1): 17, 2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-34873664

RESUMEN

As well known, the electrochemiluminescence (ECL) of tris(2,2'-bipyridine)ruthenium(II) (Ru(bpy)32+) heavily relies on highly positive or negative triggered voltage, prejudicing the detection toward the bio-molecules. In this work, Ru(bpy)32+ could generate enhanced and stable ECL at a low potential of 0.05 V (vs. Ag/AgCl) on graphene-PtPd hybrid, attributing to its excellent electrocatalysis from the synergistic effect between Pt and Pd. The obtained low-potential-driven ECL could be quenched by MoS2 nanoflowers. Based on the quenching effect, a sandwich "signal-off" ECL immunosensor was fabricated to sensitively detect carcinoembryonic antigen (CEA). A linear calibration curve from 1 fg mL-1 to 1 ng mL-1 was obtained along with a low detection limit of 0.54 fg mL-1 (S/N = 3) under optimal conditions. The sensor showed satisfactory specificity, stability, and reproducibility and was successfully applied to determine CEA in actual samples. The recoveries ranged from 98.80 to 100.23%, and the relative standard deviation (RSD) was lower than 5%. Above all, this work explored new materials in low-potential-driven ECL system and provided a reliable sensing strategy for clinical applications.


Asunto(s)
Antígeno Carcinoembrionario/sangre , Técnicas Electroquímicas/métodos , Inmunoensayo/métodos , Sustancias Luminiscentes/química , Nanocompuestos/química , Compuestos Organometálicos/química , Anticuerpos Inmovilizados/inmunología , Antígeno Carcinoembrionario/inmunología , Disulfuros/química , Grafito/química , Humanos , Límite de Detección , Molibdeno/química , Paladio/química , Platino (Metal)/química , Reproducibilidad de los Resultados
13.
Nat Commun ; 12(1): 4966, 2021 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-34404784

RESUMEN

Although chirality is an ever-present characteristic in biology and some artificial molecules, controlling the chirality and demystifying the chirality origin of complex assemblies remain challenging. Herein, we report two homochiral Ag14 nanoclusters with inherent chirality originated from identical rotation of six square faces on a Ag8 cube driven by intra-cluster π···π stacking interaction between pntp- (Hpntp = p-nitrothiophenol) ligands. The spontaneous resolution of the racemic (SD/rac-Ag14a) to homochiral nanoclusters (SD/L-Ag14 and SD/R-Ag14) can be realized by re-crystallizing SD/rac-Ag14a in acetonitrile, which promotes the homochiral crystallization in solid state by forming C-H···O/N hydrogen bonds with nitro oxygen atoms in pntp- or aromatic hydrogen atoms in dpph (dpph = 1,6-bis(diphenylphosphino)hexane) on Ag14 nanocluster. This work not only provides strategic guidance for the syntheses of chiral silver nanoclusters in an all-achiral environment, but also deciphers the origin of chirality at molecular level by identifying the special effects of intra- and inter-cluster supramolecular interactions.


Asunto(s)
Cristalización , Compuestos Organometálicos/química , Fenómenos Físicos , Plata/química , Acetonitrilos/química , Cristalografía por Rayos X , Hexanos , Hidrógeno , Enlace de Hidrógeno , Modelos Moleculares , Conformación Molecular , Oxígeno , Rotación
14.
Analyst ; 146(8): 2705-2711, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33751013

RESUMEN

A novel ratiometric electrochemical biosensing strategy based on T7 exonuclease (T7 Exo)-assisted homogenous target recycling coupling hairpin assembly triggered dual-signal output was proposed for the accurate and sensitive detection of microRNA-141 (miRNA-141). Concretely, in the presence of target miRNA, abundant signal transduction probes were released via the T7 Exo-assisted homogenous target recycling amplification, which could be captured by the specially designed ferrocene-labeled hairpin probe (Fc-H1) on -electrode interface and triggered the nonenzymatic catalytic hairpin assembly (Fc-H1 + MB-H2) to realize the cascade signal amplification and dual-signal output. Through such a conformational change process, the electrochemical signal of Fc (IFc) and MB (IMB) is proportionally and substantially decreased and increased. Therefore, the signal ratio of IMB/IFc can be employed to accurately reflect the true level of original miRNA. Benefiting from the efficient integration of the T7 Exo-assisted target recycle, nonenzymatic hairpin assembly and dual-signal output mode, the proposed sensor could realize the amplified detection of miRNA-141 effectively with a wide detection range from 1 fM to 100 pM, and a detection limit of 200 aM. Furthermore, it exhibits outstanding sequence specificity to discriminate mismatched RNA, acceptable reproducibility and feasibility for real sample. This strategy effectively integrated the advantages of multiple amplification and ratiometric output modes, which could provide an accurate and efficient method in biosensing and clinical diagnosis.


Asunto(s)
Técnicas Biosensibles , MicroARNs , Técnicas Electroquímicas , Exodesoxirribonucleasas , Límite de Detección , MicroARNs/genética , Reproducibilidad de los Resultados
15.
Acta Pharmaceutica Sinica ; (12): 476-486, 2021.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-873766

RESUMEN

Compared with normal tissues and cells, the tumor microenvironment has significant differences. For example, glutathione-related metabolic enzymes and reactive oxygen species are highly expressed in different subcellular structures, resulting in an unbalanced redox state. Aiming at the specific redox state in tumor tissues and cells, a series of small molecule prodrug self-assembled nanoparticles can be designed and connected by intelligent response linkers including disulfide bonds, sulfide bonds, and selenium bonds, thioketal bonds, etc. The in vitro and in vivo efficiency and metabolic mode of these nanoparticles are related to the type of linker. This review will summarize the tumor redox microenvironment, the design of intelligent responsive small molecule prodrug nanoparticles, and the metabolic pathways of small molecule prodrug nanoparticles with different connecting linkers and their relationship with drug efficacy.

16.
Chem Commun (Camb) ; 56(75): 11074-11077, 2020 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-32812587

RESUMEN

A DNA immobilization-free ECL aptasensor was developed for the detection of 8-hydroxy-2'-deoxygunosine based on the diffusion mediated ECL quenching effect. This ECL aptasensor exhibited a high sensitivity and low detection limit by combining homogeneous DNA reaction with dual signal amplifications: target-induced multi-DNA release and Exo I-assisted target recycling.

17.
Acta Pharmaceutica Sinica ; (12): 1932-1940, 2020.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-825162

RESUMEN

Cerasomes with different shapes were constructed to investigate the effect of the nanocarriers' shape on the cellular uptake and transmembrane capacity. Cerasome-forming lipid (CFL) was synthesized via halogenation, nucleophilic addition and acylation reaction and detected by mass spectrometry and nuclear magnetic resonance spectroscopy. CFL and short chain 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC) were employed to prepare organic-inorganic hybrid bicelles in discal shapes (nanodisc) by the thin-film hydration method, and CFL was also used to prepare spherical cerasomes (nanosphere). The particle size and zeta potential of nanocarriers were measured by dynamic light scattering analysis, and the morphology was observed by transmission electron microscopy. With human colon cancer cell line Caco-2 as the model, the effect of the shape of nanocarriers on cellular uptake and transmembrane capacity was investigated qualitatively by confocal laser scanning microscope (CLSM), and the transmembrane capacity was analyzed quantitatively by high performance liquid chromatography (HPLC). The results showed that nanosphere and nanodisc had similar particle diameters around 110 nm and similar zeta potential around -25 mV, with regular morphology under transmission electron microscope. The cellular uptake rate of nanodisc was significantly higher than that of nanosphere in 20 minutes. Further research on Caco-2 cell monolayer demonstrated that nanodisc with faster uptake had less accumulation in the monolayer, which means it had a higher transmembrane rate on Caco-2 cell monolayer and the transmembrane capacity of the nanodisc was better than that of nanosphere within 2 h. These results suggest that rational design of the shape of nanocarriers is expected to regulate nano-bio interactions, promote the transmembrane transport of nanocarriers, and improve the drug absorption.

18.
Biosens Bioelectron ; 144: 111669, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31494507

RESUMEN

8-Hydroxy-2'-deoxyguanosine (8-OH-dG) is a principal stable marker of DNA oxidative damage. Sensitive and specific detection of 8-OH-dG is of great importance for early disease diagnosis. In this paper, we developed an electrochemiluminescence aptasensor for 8-OH-dG detection based on target induced multi-DNA release and nicking enzyme signaling amplification strategy. First, three kinds of short DNAs were aligned on the aptamers immobilized on the magnetic beads. In the presence of 8-OH-dG, the aptamer recognized and specifically bound with 8-OH-dG, leading to the release of three kinds of short DNAs and three-fold signal amplification. Then the released short DNAs hybridized with ferrocence (Fc) labeled hairpin DNA (Fc-HP) immobilized on the gold electrode to form a double strand DNA. Subsequently, nicking endonuclease (Nt.AlwI) recognized the asymmetric sequence in the dsDNA and cleaved the substrate strand (Fc-HP) into two parts, one fragments containing Fc would leave the surface of electrode. Based on the quenching effect of Fc on the electrochemiluminescence (ECL) of Ru(bpy)32+/TPA, a signal-on ECL aptasensor was developed. At the same time, three kinds of short DNAs were released again and reused to initiate the repeated cycles of hybridization-cleavage. Under double signal amplification, this aptasensor achieved a low detection of 25 fM and a wide linear range from 100 fM to 10 nM for 8-OH-dG. Besides, the amount of 8-OH-dG in urine samples derived from different people were determined with satisfactory results.


Asunto(s)
8-Hidroxi-2'-Desoxicoguanosina/aislamiento & purificación , Técnicas Biosensibles , ADN/química , Técnicas de Amplificación de Ácido Nucleico/métodos , 8-Hidroxi-2'-Desoxicoguanosina/química , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/genética , ADN/genética , Roturas del ADN de Cadena Simple , Oro/química , Humanos , Mediciones Luminiscentes/métodos , Nanopartículas del Metal/química , Hibridación de Ácido Nucleico
19.
Talanta ; 200: 503-510, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31036215

RESUMEN

In this work, an ultrasensitive aptasensor for the detection of Mucin 1 (MUC1) was presented based on the target-induced catalytic hairpin assembly combined with excellent mimic peroxidase performance of PtPd bimetallic nanoparticles (PtPdNPs). Traditionally, the cyclic reuse of target protein was achieved by protein conversion with enzyme cleavage or polymerization, which is costly and complex. However, in this work, it can be performed by simple strand displacement. In addition, PtPdNPs, a mimic peroxidase, was used a probe to catalyze the oxidation of tetramethylbenzidine (TMB) by H2O2, leading to the electrochemical signal amplification. With this ingenious design, the prepared aptasensor for MUC1 detection showed a favorable linear response from 100 fg mL-1 to 1 ng mL-1 and a relatively low detection limit of 16 fg mL-1. The proposed biosensor possessed acceptable stability, selectivity and reproducibility for MUC1 assay. Additionally, the fabricated aptasensor has been successfully applied to detect MUC1 in serum samples with satisfactory results. This new strategy supplied one efficient approach to improve signal amplification, which also open an avenue for sensitivity enhancement in targets detection.


Asunto(s)
Aptámeros de Nucleótidos/química , Técnicas Electroquímicas , Nanopartículas del Metal/química , Mucina-1/análisis , Bencidinas/química , Técnicas Biosensibles , Catálisis , Humanos , Peróxido de Hidrógeno/química , Oxidación-Reducción , Paladio/química , Peroxidasa/química , Peroxidasa/metabolismo , Platino (Metal)/química
20.
Acta Pharmaceutica Sinica ; (12): 1288-1296, 2019.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-780224

RESUMEN

CY-1-4 is a tryptanthrin derivative exhibiting antitumor activity. The solubility of CY-1-4 was poor and the corresponding mechanism needs further study. To solve this problem, we prepared nanoparticles encapsulated with CY-1-4 (CY-1-4 NPs) by nanoprecipitation method using poly(caprolactone) (PCL) and poly(ethylene glycol)-co-poly(ε-caprolactone) (PEG-PCL) as carriers to improve solubility. We then explored whether CY-1-4 NPs induced B16-F10 cytotoxicity via ferroptosis by determining the effect of CY-1-4 NPs on reactive oxygen (ROS) levels, repairing efficacy of lipid reactive oxygen inhibitor ferrostatin-1 and iron chelator deferoxamine (DFO), and potentiation of protoporphyrin (PPIX) induced B16-F10 cell death. The results showed that nanoparticlated strategy significantly improved solubility of CY-1-4. With the particle size about 116 nm, encapsulating efficacy was about 83% and the drug loading capacity was about 4.80%. Ferroptosis mechanistic studies indicated that CY-1-4 NPs could improve the ROS level in B16-F10 cells, whereas ferrostatin-1 and DFO could partly inhibited the cytotoxicity and PPIX could potentiated the cytotoxicity of CY-1-4 NPs in B16-F10 cells. These results showed that ferroptosis was one of the cell death mechanisms induced by tryptanthrin derivative CY-1-4 nanoparticle.

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