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1.
Nat Nanotechnol ; 19(1): 106-114, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37709951

RESUMO

Quantum biological tunnelling for electron transfer is involved in controlling essential functions for life such as cellular respiration and homoeostasis. Understanding and controlling the quantum effects in biology has the potential to modulate biological functions. Here we merge wireless nano-electrochemical tools with cancer cells for control over electron transfer to trigger cancer cell death. Gold bipolar nanoelectrodes functionalized with redox-active cytochrome c and a redox mediator zinc porphyrin are developed as electric-field-stimulating bio-actuators, termed bio-nanoantennae. We show that a remote electrical input regulates electron transport between these redox molecules, which results in quantum biological tunnelling for electron transfer to trigger apoptosis in patient-derived cancer cells in a selective manner. Transcriptomics data show that the electric-field-induced bio-nanoantenna targets the cancer cells in a unique manner, representing electrically induced control of molecular signalling. The work shows the potential of quantum-based medical diagnostics and treatments.


Assuntos
Apoptose , Neoplasias , Humanos , Transporte de Elétrons , Oxirredução , Morte Celular , Ouro/química
2.
J Colloid Interface Sci ; 462: 154-65, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26454374

RESUMO

The preparation of novel porphyrin derivatives and their immobilization onto iron oxide nanoparticles to build up suitable nanotools for potential use in photodynamic therapy (PDT) has been explored. To achieve this purpose, a zinc porphyrin derivative, ZnPR-COOH, has been synthesized, characterized at the molecular level and immobilized onto previously synthesized iron oxide nanoparticles covered with oleylamine. The novel nanosystem (ZnPR-IONP) has been thoroughly characterized by a variety of techniques such as UV-Vis absorption spectroscopy, fluorescence spectroscopy, X-ray photoloectron spectroscopy (XPS) and transmission electron microscopy (TEM). In order to probe the capability of the photosensitizer for PDT, the singlet oxygen production of both ZnPR-IONP and the free ligand ZnPR-COOH have been quantified by measuring the decay in absorption of the anthracene derivative 9,10-anthracenedipropionic acid (ADPA), showing an important increase on singlet oxygen production when the porphyrin is incorporated onto the IONP (ZnPR-IONP). On the other hand, the porphyrin derivative PR-TRIS3OH, incorporating several polar groups (TRIS), was synthesized and immobilized with the intention of obtaining water soluble nanosystems (PR-TRIS-IONP). When the singlet oxygen production ability was evaluated, the values obtained were similar to ZnPR-COOH/ZnPR-IONP, again much higher in the case of the nanoparticles PR-TRIS-IONP, with more than a twofold increase. The efficient singlet oxygen production of PR-TRIS-IONP together with their water solubility, points to the great promise that these new nanotools represent for PDT.


Assuntos
Compostos Férricos/química , Nanopartículas/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/química , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Porfirinas/síntese química
4.
ACS Nano ; 8(1): 818-26, 2014 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-24354268

RESUMO

A spatially controlled synthesis of nanowire bundles of the functional crystalline coordination polymer (CP) Ag(I)TCNQ (tetracyanoquinodimethane) from previously fabricated and trapped monovalent silver CP (Ag(I)Cys (cysteine)) using a room-temperature microfluidic-assisted templated growth method is demonstrated. The incorporation of microengineered pneumatic clamps in a two-layer polydimethylsiloxane-based (PDMS) microfluidic platform was used. Apart from guiding the formation of the Ag(I)Cys coordination polymer, this microfluidic approach enables a local trapping of the in situ synthesized structures with a simple pneumatic clamp actuation. This method not only enables continuous and multiple chemical events to be conducted upon the trapped structures, but the excellent fluid handling ensures a precise chemical activation of the amino acid-supported framework in a position controlled by interface and clamp location that leads to a site-specific growth of Ag(I)TCNQ nanowire bundles. The synthesis is conducted stepwise starting with Ag(I)Cys CPs, going through silver metal, and back to a functional CP (Ag(I)TCNQ); that is, a novel microfluidic controlled ligand exchange (CP → NP → CP) is presented. Additionally, the pneumatic clamps can be employed further to integrate the conductive Ag(I)TCNQ nanowire bundles onto electrode arrays located on a surface, hence facilitating the construction of the final functional interfaced systems from solution specifically with no need for postassembly manipulation. This localized self-supported growth of functional matter from an amino acid-based CP shows how sequential localized chemistry in a fluid cell can be used to integrate molecular systems onto device platforms using a chip incorporating microengineered pneumatic tools. The control of clamp pressure and in parallel the variation of relative flow rates of source solutions permit deposition of materials at different locations on a chip that could be useful for device array preparation. The in situ reaction and washing procedures make this approach a powerful one for the fabrication of multicomponent complex nanomaterials using a soft bottom-up approach.

5.
Chem Commun (Camb) ; (10): 1255-7, 2005 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-15742043

RESUMO

A tetra(thiafulvalene-crown-ether) phthalocyanine self-assembles into helical tapes nanometers wide and micrometers long. Formation of these scrolled molecular architectures is a first for phthalocyanine fibres and shows potential as a novel conducting material.

6.
J Org Chem ; 67(3): 1004-7, 2002 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-11856052

RESUMO

A new AB(4)-type hypermonomer with four activated aromatic fluorines was prepared and converted to hyperbranched poly(ether ketones) by nucleophilic aromatic substitution of these fluorine atoms with phenolates. The preparation and application of the AB(4) hypermonomer for the accelerated synthesis of a family of poly(ether ketone) dendrons G2-G4 in good yield are described.

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