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1.
Carbohydr Polym ; 334: 122068, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553197

RESUMO

The fabrication of highly elastic, fatigue-resistant and conductive hydrogels with antibacterial properties is highly desirable in the field of wearable devices. However, it remains challenging to simultaneously realize the above properties within one hydrogel without compromising excellent sensing ability. Herein, we fabricated a highly elastic, fatigue-resistant, conductive, antibacterial and cellulose nanocrystal (CNC) enhanced hydrogel as a sensitive strain sensor by the synergistic effect of biosynthesized selenium nanoparticles (BioSeNPs), MXene and nanocellulose. The structure and potential mechanism to generate biologically synthesized SeNPs (BioSeNPs) were systematically investigated, and the role of protease A (PrA) in enhancing the adsorption between proteins and SeNPs was demonstrated. Additionally, owing to the incorporation of BioSeNPs, CNC and MXene, the synthesized hydrogels showed high elasticity, excellent fatigue resistance and antibacterial properties. More importantly, the sensitivity of hydrogels determined by the gauge factor was as high as 6.24 when a high strain was applied (400-700 %). This study provides a new horizon to synthesize high-performance antibacterial and conductive hydrogels for soft electronics applications.


Assuntos
Nanopartículas , Nitritos , Selênio , Elementos de Transição , Antibacterianos/farmacologia , Celulose/farmacologia , Condutividade Elétrica , Hidrogéis/farmacologia
2.
J Colloid Interface Sci ; 665: 389-398, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38537587

RESUMO

Photothermal therapy (PTT) has attracted much attention due to its less invasive, controllable and highly effective nature. However, PTT also suffers from intrinsic cancer resistance mediated by cell survival pathways. These survival pathways are regulated by a variety of proteins, among which heat shock protein (HSP) triggers thermotolerance and protects tumor cells from hyperthermia-induced apoptosis. Confronted by this challenge, we propose and validate here a novel MXene-based HSP-inhibited mild photothermal platform, which significantly enhances the sensitivity of tumor cells to heat-induced stress and thus improves the PPT efficacy. The Ti3C2@Qu nanocomposites are constructed by utilizing the high photothermal conversion ability of Ti3C2 nanosheets in combination with quercetin (Qu) as an inhibitor of HSP70. Qu molecules are loaded onto the nanoplatform in a pH-sensitive controlled release manner. The acidic environment of the tumor causes the burst-release of Qu molecules, which deplete the level of heat shock protein 70 (HSP70) in tumor cells and leave the tumor cells out from the protection of the heat-resistant survival pathway in advance, thus sensitizing the hyperthermia efficacy. The nanostructure, photothermal properties, pH-responsive controlled release, synergistic photothermal ablation of tumor cells in vitro and in vivo, and hyperthermia effect on subcellular structures of the Ti3C2@Qu nanocomposites were systematically investigated.


Assuntos
Hipertermia Induzida , Nanocompostos , Nanopartículas , Neoplasias , Nitritos , Elementos de Transição , Humanos , Preparações de Ação Retardada , Titânio/farmacologia , Fototerapia , Neoplasias/terapia , Linhagem Celular Tumoral , Nanopartículas/química
3.
Chemosphere ; 352: 141339, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301838

RESUMO

In this study, we successfully developed a hybrid architecture referred to as MoS2@MX, involving the integration of MoS2 layered onto MXene using a straightforward co-precipitation method. This innovative hybrid photocatalyst exhibited remarkable efficiency in removing oxytetracycline (OTC) molecules from aqueous solutions under visible-light irradiation. During the photocatalytic process, both MoS2 and MX played distinct yet complementary roles. MoS2 facilitated efficient electron transfer, while MX contributed to the generation of radicals. This unique collaboration resulted in a noteworthy 99 % oxidation efficiency for OTC degradation within a brief 60 min of visible light exposure in an aqueous environment. The radicals 1O2 and •OH were identified as the principal drivers behind OTC degradation, underscoring the vital role of the hybrid material. Mechanistically, the degradation of OTC involved several key steps, including C-H bond cleavage, de-carboxylation, C-N bond oxidation, and de-chlorination. Importantly, the MoS2@MX hybrid composite demonstrated remarkable stability, maintaining a noteworthy photocatalytic efficiency of 89 % for targeted OTC removal after undergoing five consecutive cycles. In conclusion, this study emphasizes the potential of the MoS2@MX hybrid material as an effective agent for degrading organic OTC compounds within aquatic environments. The hybrid's multifaceted roles and exceptional performance suggest promising applications in sustainable water treatment.


Assuntos
Molibdênio , Nitritos , Oxitetraciclina , Elementos de Transição , Transporte de Elétrons , Halogenação
4.
ACS Appl Mater Interfaces ; 16(8): 9968-9979, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38358298

RESUMO

Foreseen as foundational in forthcoming oncology interventions are multimodal therapeutic systems. Nevertheless, the tumor microenvironment (TME), marked by heightened glucose levels, hypoxia, and scant concentrations of endogenous hydrogen peroxide could potentially impair their effectiveness. In this research, two-dimensional (2D) Ti3C2 MXene nanosheets are engineered with CeO2 nanozymes and glucose oxidase (GOD), optimizing them for TME, specifically targeting cancer therapy. Following our therapeutic design, CeO2 nanozymes, embodying both peroxidase-like and catalase-like characteristics, enable transformation of H2O2 into hydroxyl radicals for catalytic therapy while also producing oxygen to mitigate hypoxia. Concurrently, GOD metabolizes glucose, thereby augmenting H2O2 levels and disrupting the intracellular energy supply. When subjected to a near-infrared laser, 2D Ti3C2 MXene accomplishes photothermal therapy (PTT) and photodynamic therapy (PDT), additionally amplifying cascade catalytic treatment via thermal enhancement. Empirical evidence demonstrates robust tumor suppression both in vitro and in vivo by the CeO2/Ti3C2-PEG-GOD nanocomposite. Consequently, this integrated approach, which combines PTT/PDT and enzymatic catalysis, could offer a valuable blueprint for the development of advanced oncology therapies.


Assuntos
Hipertermia Induzida , Neoplasias , Nitritos , Elementos de Transição , Humanos , Glucose Oxidase , Peróxido de Hidrogênio , Titânio/farmacologia , Hipertermia , Neoplasias/terapia , Glucose , Hipóxia , Microambiente Tumoral , Linhagem Celular Tumoral
5.
J Am Chem Soc ; 146(3): 2102-2112, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38225538

RESUMO

Recent therapeutic strategies suggest that small peptides can act as aggregation inhibitors of monomeric amyloid-ß (Αß) by inducing structural rearrangements upon complexation. However, characterizing the binding events in such dynamic and transient noncovalent complexes, especially in the presence of natively occurring metal ions, remains a challenge. Here, we deploy a combined transition metal ion Förster resonance energy transfer (tmFRET) and native ion mobility-mass spectrometry (IM-MS) approach to characterize the structure of mass- and charge-selected Aß complexes with Cu(II) ions (a quencher) and a potential aggregation inhibitor, a small neuropeptide named leucine enkephalin (LE). We show conformational changes of monomeric Αß species upon Cu(II)-binding, indicating an uncoiled N-terminus and a close interaction between the C-terminus and the central hydrophobic region. Furthermore, we introduce LE labeled at the N-terminus with a metal-chelating agent, nitrilotriacetic acid (NTA). This allows us to employ tmFRET to probe the binding even in low-abundance and transient Aß-inhibitor-metal ion complexes. Complementary intramolecular distance and global shape information from tmFRET and native IM-MS, respectively, confirmed Cu(II) displacement toward the N-terminus of Αß, which discloses the binding region and the inhibitor's orientation.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Elementos de Transição , Ligantes , Peptídeos beta-Amiloides/química , Metais/química , Íons , Cobre/química
6.
J Mater Chem B ; 12(5): 1379-1392, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38247429

RESUMO

To date, implant-associated infection is still a significant clinical challenge, which cannot be effectively eliminated by single therapies due to the formation of microbial biofilms. Herein, a pH-responsive nanoplatform was constructed via the in situ growth of zinc sulfide (ZnS) nanoparticles on the surface of Ti3C2 MXene nanosheets, which was subsequently introduced in poly(L-lactic acid) (PLLA) to prepare a composite bone scaffold via selective laser sintering technology. In the acidic biofilm microenvironment, the degradation of ZnS released hydrogen sulfide (H2S) gas to eliminate the biofilm extracellular DNA (eDNA), thus destroying the compactness of the biofilm. Then, the bacterial biofilm became sensitive to hyperthermia, which could be further destroyed under near-infrared light irradiation due to the excellent photothermal property of MXene, finally achieving gas/photothermal synergistic antibiofilm and efficient sterilization. The results showed that the synergistic gas/photothermal therapy for the composite scaffold not only evidently inhibited the formation of biofilms, but also effectively eradicated the eDNA of the already-formed biofilms and killed 90.4% of E. coli and 84.2% of S. aureus under near infrared light irradiation compared with single gas or photothermal therapy. In addition, the composite scaffold promoted the proliferation and osteogenic differentiation of mouse bone marrow mesenchymal stem cells. Thus, the designed scaffold with excellent biofilm elimination and osteogenesis ability has great potential as an alternative treatment for implant-associated bone infections.


Assuntos
Hipertermia Induzida , Nitritos , Terapia Fototérmica , Elementos de Transição , Camundongos , Animais , Staphylococcus aureus , Osteogênese , Escherichia coli , Raios Infravermelhos , Biofilmes , Concentração de Íons de Hidrogênio , Ácido Láctico
7.
Nat Commun ; 15(1): 762, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38278810

RESUMO

A wearable biological patch capable of producing multiple responses to light and electricity without interfering with daily activities is highly desired for skin cancer treatment, but remains a key challenge. Herein, the skin-mountable electrostimulation-augmented photothermal patch (eT-patch) comprising transparent ionic gel with MXene (Ti3C2Tx) doping is developed and applied for the treatment of melanoma under photostimulation at 0.5 W/cm2. The eT-patch designed has superior photothermal and electrical characteristics owing to ionic gels doped with MXene which provides high photothermal conversion efficiency and electrical conductivity as a medium. Simultaneously, the ionic gel-based eT-patch having excellent optical transparency actualizes real-time observation of skin response and melanoma treatment process under photothermal and electrical stimulation (PES) co-therapy. Systematical cellular study on anti-tumor mechanism of the eT-patch under PES treatment revealed that eT-patch under PES treatment can synergically trigger cancer cell apoptosis and pyroptosis, which together lead to the death of melanoma cells. Due to the obvious advantages of relatively safe and less side effects in healthy organs, the developed eT-patch provides a promising cost-effective therapeutic strategy for skin tumors and will open a new avenue for biomedical applications of ionic gels.


Assuntos
Terapia por Estimulação Elétrica , Melanoma , Nitritos , Neoplasias Cutâneas , Elementos de Transição , Dispositivos Eletrônicos Vestíveis , Humanos , Melanoma/terapia , Neoplasias Cutâneas/terapia , Géis , Íons
8.
J Biomol Struct Dyn ; 42(3): 1145-1156, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37066617

RESUMO

Two-dimensional (2D) nanomaterials can improve drug delivery by reducing toxicity, increasing bioavailability and boosting efficacy. In this study, the simultaneous use of transition metal carbides and nitrides (MXenes) along with copper (II) benzene-1, 3, 5-tricarboxylate metal-organic framework (Cu - BTC/MOF) as attractive nanocarriers are investigated for loading and delivering curcumin (CUR) and paclitaxel (PTX) drugs to cancer cells. The efficiency of surface termination (bare and oxygen) in the adsorption of PTX and CUR drugs and the co-loading of these two drugs are evaluated. Our results show that the strongest interaction energy belongs to the adsorption of drug CUR on the MXNNO-Cu-BTC adsorbent, while the interaction of PTX drug with the MXNO- Cu-BTC in the MXNO-Cu-BTC/PTX&CUR system is the lowest due to the particular structure of the drug and the adsorbent. Our results show that at the beginning simulation, the interaction energy between the PTX drug and water in PTX/MXN system is -4645.48 kJ/mol, which reduces to -3848.71 kJ/mol after the system reaches equilibrium. Therefore, the inspected adsorbents have a good performance in adsorbing CUR and PTX drugs. The obtained results from this investigation provide valuable information about experimental studies by medical scientists in the future.Communicated by Ramaswamy H. Sarma.


Assuntos
Curcumina , Neoplasias , Nitritos , Elementos de Transição , Paclitaxel/farmacologia , Paclitaxel/química , Curcumina/farmacologia , Curcumina/química , Adsorção , Cobre/química , Água , Neoplasias/tratamento farmacológico
9.
Small ; 20(4): e2304119, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37759420

RESUMO

Although antibiotic is still the main choice for antibacteria both in hospital and community, phototherapy has become a possibly one of the alternative approaches in the treatment of microbe-associated infections nowadays because of its considerable potential in effective eradication of pathogenic bacteria. However, overwhelming reactive oxygen species (ROS) generated from phototherapy inevitably provoke an inflammatory response, complicating the healing process. To address this outstanding issue, a MXene-decorated nanofibrious is devised that not only yield localized heat but also elevate ROS levels under near-infrared laser exposure ascribed to the synergistic photothermal/photodynamic effect, for potent bacterial inactivation. After being further loaded with aspirin, the nanofibrous membranes exhibit benign cytocompatibility, boosting cell growth and suppressing the (nuclear factor kappa-B ( NF-κB) signaling pathways through RNA sequencing analysis, indicating an excellent anti-inflammatory effect. Interestingly, in vivo investigations also corroborate that the nanofibrous membranes accelerate infectious cutaneous regeneration by efficiently killing pathogenic bacteria, promoting collagen deposition, boosting angiogenesis, and dampening inflammatory reaction via steering NF-κB pathway. As envisaged, this work furnishes a decorated nanofibrous membrane with programmed antibacterial and anti-inflammatory effects for remedy of refractory bacteria-invaded wound regeneration.


Assuntos
NF-kappa B , Nanofibras , Nitritos , Elementos de Transição , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Cicatrização , Anti-Inflamatórios/farmacologia , Antibacterianos/farmacologia
10.
Anal Biochem ; 685: 115404, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-37993043

RESUMO

In the category of 2D materials, MoS2 a transition metal dichalcogenide, is a novel and intriguing class of materials with interesting physicochemical properties, explored in applications ranging from cutting-edge optoelectronic to the frontiers of biomedical and biotechnology. MoS2 nanostructures an alternative to heavy toxic metals exhibit biocompatibility, low toxicity and high stability, and high binding affinity to biomolecules. MoS2 nanostructures provide a lot of opportunities for the advancement of novel biosensing, nanodrug delivery system, electrochemical detection, bioimaging, and photothermal therapy. Much efforts have been made in recent years to improve their physiochemical properties by developing a better synthesis approach, surface functionalization, and biocompatibility for their safe use in the advancement of biomedical applications. The understanding of parameters involved during the development of nanostructures for their safe utilization in biomedical applications has been discussed. Computational studies are included in this article to understand better the properties of MoS2 and the mechanism involved in their interaction with biomolecules. As a result, we anticipate that this combined experimental and computational studies of MoS2 will inspire the development of nanostructures with smart drug delivery systems, and add value to the understanding of two-dimensional smart nano-carriers.


Assuntos
Nanoestruturas , Elementos de Transição , Molibdênio/química , Nanoestruturas/química , Sistemas de Liberação de Medicamentos
11.
Talanta ; 270: 125548, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38104427

RESUMO

The use of two-dimensional heterostructure composite as electrode modification material has become a new strategy to improve the electrocatalytic activity and electroactive sites of electrochemical sensor. Herein, a soluble heterostructure, namely rGO-PSS@MXene, was designed and synthesized by integrating poly (sodium p-styrenesulfonate)-functionalized reduced graphene oxide into MXene nanosheets via ultrasonic method. The interactive heterostructure can effectively alleviate the self-stacking of MXene and rGO, endowing them with superior electron transfer capacity and large specific surface area, thereby producing prominent synergistic electrocatalytic effect towards rutin. In addition, the excellent enrichment effect of rGO-PSS@MXene for rutin also plays an important role through the electrostatic and π-π stacking interactions. The electrochemical characteristics of rutin on the sensor were examined in detail and a sensitive sensing method was proposed. Under optimized conditions, the method showed satisfactory linear relationship for rutin in the concentration range of 0.005-10.0 µM, with limit of detection of 1.8 nM (S/N = 3). The quantitative validation results in herbal medicine and commercial Tartary buckwheat tea were highly consistent with the labeled quantity and the results of HPLC determination, respectively, suggesting the sensor possessed excellent selectivity and accuracy. This proposed strategy for rutin determination is expected to expand the application of MXene heterostructure in electrochemical sensors, and is envisioned as a promising candidate for quality monitoring of drugs and foods.


Assuntos
Fagopyrum , Grafite , Nitritos , Elementos de Transição , Rutina/análise , Grafite/química , Fagopyrum/química , Chá , Técnicas Eletroquímicas/métodos
12.
J Org Chem ; 87(24): 16368-16377, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36449039

RESUMO

The tetradentate azamacrocycle cyclam (=1,4,8,11-tetraazacyclotetradecane) was studied profoundly for the coordination of transition metal ions, and the resulting complexes were investigated extensively for their catalytic performance in, e.g., O2 activation and electrocatalytic CO2 reduction. Although the successful synthesis of analogous P4 macrocycles was described earlier, no tetradentate N,P mixed 14-membered macrocycles have been prepared to date and their chemistry remains elusive. Thus, in this work, we showcase the synthesis of phospha-aza mixed cyclam-based macrocycles by selectively "exchanging" one or two secondary amines in the macrocycle isocyclam (=1,4,7,11-tetraazacyclotetradecane) with tertiary phosphines. In addition, we herein present the preparation of the corresponding nickel complexes along with their complex chemical and structural characterization to provide first coordination studies.


Assuntos
Ciclamos , Elementos de Transição , Níquel/química , Fósforo , Modelos Moleculares , Elementos de Transição/química
13.
J Am Chem Soc ; 144(47): 21443-21447, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36378626

RESUMO

Hydride transfer catalysis is shown to be enabled by the nonspectator reactivity of a transition metal-bound low-symmetry tricoordinate phosphorus ligand. Complex 1·[Ru]+, comprising a nontrigonal phosphorus chelate (1, P(N(o-N(2-pyridyl)C6H4)2) and an inert metal fragment ([Ru] = (Me5C5)Ru), reacts with NaBH4 to give a metallohydridophosphorane (1H·[Ru]) by P-H bond formation. Complex 1H·[Ru] is revealed to be a potent hydride donor (ΔG°H-,exp < 41 kcal/mol, ΔG°H-,calc = 38 ± 2 kcal/mol in MeCN). Taken together, the reactivity of the 1·[Ru]+/1H·[Ru] pair comprises a catalytic couple, enabling catalytic hydrodechlorination in which phosphorus is the sole reactive site of hydride transfer.


Assuntos
Fósforo , Elementos de Transição , Ligantes , Catálise , Elementos de Transição/química , Metais
14.
J Am Chem Soc ; 144(37): 16684-16697, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36070395

RESUMO

Appetite for reactions involving PH3 has grown in the past few years. This in part is due to the ability to generate PH3 cleanly and safely via digestion of cheap metal phosphides with acids, thus avoiding pressurized cylinders and specialized equipment. In this perspective we highlight current trends in forming new P-C/P-OC bonds with PH3 and discuss the challenges involved with selectivity and product separation encumbering these reactions. We highlight the reactivity of PH3 with main group reagents, building on the early pioneering work with transition metal complexes and PH3. Additionally, we highlight the recent renewal of interest in alkali metal sources of H2P- which are proving to be useful synthons for chemistry across the periodic table. Such MPH2 sources are being used to generate the desired products in a more controlled fashion and are allowing access to unexplored phosphorus-containing species.


Assuntos
Complexos de Coordenação , Elementos de Transição , Complexos de Coordenação/química , Metais , Fósforo/química , Elementos de Transição/química
15.
Angew Chem Int Ed Engl ; 61(45): e202210334, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36111838

RESUMO

Developing practical and mild strategies for the direct functionalization of white phosphorus (P4 ) without chlorination is an appealing but formidable challenge. To this end, we report a breakthrough in the preparation of structurally diverse dialkylphosphines and trialkylphosphines that rely on the successive generation of carbon-centered radicals from N-hydroxyphthalimide (NHPI) esters and the controllable alkylation of the P4 molecule under transition-metal- and photocatalyst-free conditions. To facilitate separation and prevent product losses during purification, the corresponding oxidation products dialkylphosphine oxides (DAPOs) and trialkylphosphine oxides (TAPOs) were isolated. This photoinduced phosphorylation reaction features one-pot operation, high product selectivity, and tolerates a broad range of alkyl NHPI esters, including derivatives of complex natural products and pharmaceuticals. Further diversified transformation of DAPOs to construct P-F, P-C, P-N, and P-O bonds was also demonstrated.


Assuntos
Óxidos , Elementos de Transição , Óxidos/química , Fósforo , Ácidos Graxos , Catálise , Fosforilação , Ésteres
16.
Acc Chem Res ; 55(5): 783-793, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35171568

RESUMO

Low-valent transition metalates─anionic, electronic-rich organometallic complexes─comprise a class of highly reactive chemical reagents that find integral applications in organic synthesis, small-molecule activation, transient species stabilization, and M-E bond formation, among others. The inherent reactivity of such electron-rich metal centers has necessitated the widespread use of strong backbonding ligands, particularly carbonyls, to aid in the isolation and handling of metalate reagents, albeit sometimes at the expense of partially masking their full reactivity. However, recent synthetic explorations into transition-metalate complexes devoid of archetypic back-bonding ligands have led to the discovery of highly reactive metalates capable of performing a variety of novel chemical transformations.Building on our group's long-standing interest in reactive organometallic species, a series of rational progressions in early-to-middle transition-metal chemistry ultimately led to our isolation of a rhenium(I) ß-diketiminate cyclopentadienide metalate that displays exceptional reactivity. We have found this Re(I) metalate to be capable of small-molecule activation; notably, the complex reversibly binds dinitrogen in solution and can be utilized to trap N2 for the synthesis of functionalized diazenido species. By employing isolobal analogues to N2 (CO and RNC), we were able to thoroughly monitor the mechanism of activation and conclude that the metalate's sodium counterion plays an integral role in promoting dinitrogen activation through a novel side-on interaction. The Re(I) metalate is also used in forming a variety of M-E bonds, including a series of uncommon rhenium-tetrylene (Si, Ge, and Sn) complexes that display varying degrees of multiple bonding. These metal tetrylenes act to highlight deviations in chemical properties within the group 14 elements. Our metalate's utility also applies to metal-metal bond formation, as demonstrated through the synthesis of a heterotetrametallic rhenium-zinc dimer. In this reaction, the Re(I) metalate performs a dual role as a reductant and metalloligand to stabilize a transient Zn22+ core fragment. Finally, the metalate displays unique reactivity with uranium(III) to yield the first transition metal-actinide inverse-sandwich bonds, in this case with three rhenium fragments bound through their Cp moieties surrounding the uranium center. Notably, throughout these endeavors we demonstrate that the metalate displays reactivity at multiple locations, including directly at the rhenium metal center, at a Cp carbon, through a Cp-sandwich mode, or through reversibly bound dinitrogen.Overall, the rhenium(I) metalate described herein demonstrates utility in diverse applications: small-molecule activation, the stabilization of reduced and/or unstable species, and the formation of unconventional M-E/M-M bonds or heterometallic complexes. Moving forward, we suggest that the continued discovery of noncarbonyl, electron-rich transition-metal anions featuring new or unconventional ligands should produce additional reactive organometallic species capable of stabilizing unique structural motifs and performing novel and unusual chemical transformations.


Assuntos
Rênio , Elementos de Transição , Ânions , Carbono/química , Ligantes , Rênio/química , Elementos de Transição/química
17.
Int J Mol Sci ; 23(3)2022 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-35163169

RESUMO

The antioxidant/pro-oxidant activity of drugs and dietary molecules and their role in the maintenance of redox homeostasis, as well as the implications in health and different diseases, have not yet been fully evaluated. In particular, the redox activity and other interactions of drugs with essential redox metal ions, such as iron and copper, need further investigation. These metal ions are ubiquitous in human nutrition but also widely found in dietary supplements and appear to exert major effects on redox homeostasis in health, but also on many diseases of free radical pathology. In this context, the redox mechanistic insights of mainly three prototype groups of drugs, namely alpha-ketohydroxypyridines (alpha-hydroxypyridones), e.g., deferiprone, anthraquinones, e.g., doxorubicin and thiosemicarbazones, e.g., triapine and their metal complexes were examined; details of the mechanisms of their redox activity were reviewed, with emphasis on the biological implications and potential clinical applications, including anticancer activity. Furthermore, the redox properties of these three classes of chelators were compared to those of the iron chelating drugs and also to vitamin C, with an emphasis on their potential clinical interactions and future clinical application prospects in cancer, neurodegenerative and other diseases.


Assuntos
Antioxidantes/farmacologia , Quelantes/química , Elementos de Transição/química , Antraquinonas/química , Antraquinonas/farmacologia , Antioxidantes/química , Quelantes/farmacologia , Complexos de Coordenação/química , Cobre/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Radicais Livres/química , Ferro/química , Quelantes de Ferro/química , Quelantes de Ferro/farmacologia , Oxirredução/efeitos dos fármacos , Piridinas/química , Piridinas/farmacologia , Espécies Reativas de Oxigênio/química , Tiossemicarbazonas/química , Tiossemicarbazonas/farmacologia
18.
Adv Sci (Weinh) ; 9(4): e2102924, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34898053

RESUMO

The combination of 2D materials and optical biosensors has become a hot research topic in recent years. Graphene, transition metal dichalcogenides, black phosphorus, MXenes, and other 2D materials (metal oxides and degenerate semiconductors) have unique optical properties and play a unique role in the detection of different biomolecules. Through the modification of 2D materials, optical biosensor has the advantages that traditional sensors (such as electrical sensing) do not have, and the sensitivity and detection limit are greatly improved. Here, optical biosensors based on different 2D materials are reviewed. First, various detection methods of biomolecules, including surface plasmon resonance (SPR), fluorescence resonance energy transfer (FRET), and evanescent wave and properties, preparation and integration strategies of 2D material, are introduced in detail. Second, various biosensors based on 2D materials are summarized. Furthermore, the applications of these optical biosensors in biological imaging, food safety, pollution prevention/control, and biological medicine are discussed. Finally, the future development of optical biosensors is prospected. It is believed that with their in-depth research in the laboratory, optical biosensors will gradually become commercialized and improve people's quality of life in many aspects.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Transferência Ressonante de Energia de Fluorescência/instrumentação , Transferência Ressonante de Energia de Fluorescência/métodos , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos , Grafite/química , Humanos , Óxidos/química , Fósforo/química , Elementos de Transição/química
19.
Molecules ; 28(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36615470

RESUMO

Traditional methods of tumor treatment such as surgical resection, chemotherapy, and radiation therapy have certain limitations, and their treatment effects are not always satisfactory. As a new tumor treatment method, photothermal therapy based on nanostructures has attracted the attention of researchers due to its characteristics of minimally invasive, low side effects, and inhibition of cancer metastasis. In recent years, there has been a variety of inorganic or organic nanostructures used in the field of photothermal tumor treatment, and they have shown great application prospects. In this paper, the advantages and disadvantages of a variety of nanomaterials/nanostructures as photothermal agents (PTAs) for photothermal therapy as well as their research progress are reviewed. For the sake of clarity, the recently reported nanomaterials/nanostructures for photothermal therapy of tumor are classified into five main categories, i.e., carbon nanostructures, noble metal nanostructures, transition metal sulfides, organic polymer, and other nanostructures. In addition, future perspectives or challenges in the related field are discussed.


Assuntos
Hipertermia Induzida , Nanoestruturas , Neoplasias , Elementos de Transição , Humanos , Neoplasias/terapia , Fototerapia , Nanoestruturas/uso terapêutico , Nanoestruturas/química
20.
Appl Opt ; 60(17): 5161-5168, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34143085

RESUMO

A surface plasmon resonance (SPR) sensor based on blue phosphorus (BlueP)/transition metal dichalcogenides (TMDCs) of two-dimensional (2D) materials is proposed to increase the performance. In this sensor, BlueP/TMDCs are coated on indium tin oxide (ITO) and different metals (Au/Ag/Cu) to improve the sensitivity. By optimizing structural parameters, with the BlueP/WS2 monolayer and Au thin film, the angular sensitivity can reach as high as 226.0°/RIU. The phase sensitivity also can be as high as 3.6001×106deg/RIU with BlueP/MoS2 4 layers, 228 nm ITO, and 25 nm Au thin film, which is 6.77 times that of the Au-ITO structure and 54.40 times that of the traditional SPR of Au thin film. The SPR sensor has potential applications in disease diagnosis, drug development, gene sequencing and treatment, environmental monitoring, food safety testing, doping testing, and other fields.


Assuntos
Técnicas Biossensoriais/instrumentação , Nanoestruturas/química , Fósforo/química , Ressonância de Plasmônio de Superfície/métodos , Compostos de Estanho/química , Elementos de Transição/química , Sensibilidade e Especificidade
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