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1.
Sci Rep ; 14(1): 5798, 2024 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461314

RESUMO

In this research, palladium (II) and platinum (II), as well as their bimetallic nanoparticles were synthesized using medicinal plants in an eco-friendly manner. Rosemary and Ginseng extracts were chosen due to their promising anticancer potential. The synthesized nanoparticles underwent characterization through FT-IR spectroscopy, DLS, XRD, EDX, SEM, and TEM techniques. Once the expected structures were confirmed, the performance of these nanoparticles, which exhibited an optimal size, was evaluated as potential anticancer agents through in vitro method on colon cancer cell lines (Ls180, SW480). MTT assay studies showed that the synthesized nanoparticles induced cell death. Moreover, real-time PCR was employed to investigate autophagy markers and the effect of nanoparticles on the apoptosis process, demonstrating a significant effect of the synthesized compounds in this regard.


Assuntos
Nanopartículas Metálicas , Panax , Rosmarinus , Paládio/química , Platina/farmacologia , Nanopartículas Metálicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/farmacologia , Extratos Vegetais/química
2.
Chemosphere ; 350: 141184, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38215834

RESUMO

Efficient recognition, separation and recovery of palladium from high-level liquid waste (HLLW) not only helps the safe, green and environmentally friendly disposal of nuclear waste, but also is an essential important supplement to overcome the growing shortage of natural palladium resources. Herein, a novel silica-based functional adsorbent named 2AT-SiAaC was prepared by a two-step method, i.e., grafting of 2-aminothiazole (2AT) via the amidated reaction after in-situ polymerization of acrylic monomers on porous silica. SEM, EDS, TG-DSC, BET and PXRD all proved the successful preparation of 2AT-SiAaC, and it exhibited ultrahigh adsorption selectivity for Pd(II) (Kd (distribution coefficient) ≥ 10,344.2 mL/g, SFPd/M (separation factor) ≥ 613.7), fast adsorption kinetics with short equilibrium time (t ≤ 1 h) and good adsorption capacity (Q ≥ 62.1 mg Pd/g). The dynamic column experiments shows that 2AT-SiAaC achieved efficiently separation of Pd(II) from simulated HLLW, and the enrichment coefficients (C/C0) of Pd(II) was as high as about 14 with the recovery rate nearly 99.9% and basically kept the same performance in three adsorption-desorption column cycle experiments. The adsorption mechanism was analyzed by FT-IR, XPS and DFT calculations, and the ultrahigh selectivity of 2AT-SiAaC was attributed to the preferred affinity of the soft N-donor atoms in 2AT for Pd(II). NO3- ions participated in the adsorption reaction to keep charge balance, and the frontier orbital electron density distribution diagram shows the charge transfer in the process of material preparation and adsorption. To sum up, 2AT-SiAaC adsorbent provided a new insight for precise recognition and efficient separation of Pd(II) from HLLW.


Assuntos
Paládio , Tiazóis , Poluentes Químicos da Água , Paládio/análise , Dióxido de Silício , Espectroscopia de Infravermelho com Transformada de Fourier , Adsorção , Cinética
3.
Food Chem ; 439: 138132, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38081094

RESUMO

The ferritin cage can not only load iron ions in its inner cavity, but also has the capacity to carry other metal ions, thus constructing a new biological nano-transport system. The nanoparticles formed by ferritin and minerals can be used as ingredients of mineral supplements, which overcome the shortcomings of traditional mineral ingredients such as low bioavailability. Moreover, ferritin can be used to remove heavy metal ions from contaminated food. Silver and palladium nanoparticles formed by ferritin are also applied as anticancer agents. Ferritin combined with metal ions can be also used to detect harmful substances. This review aims to provide a comprehensive overview of ferritin's function in transporting and binding metal ions, and discusses the limitations and future prospects, which offers valuable insights for the application of ferritin in mineral supplements, food detoxifiers, anticancer agents, and food detections.


Assuntos
Antineoplásicos , Nanopartículas Metálicas , Ferritinas/química , Paládio , Minerais/metabolismo , Íons
4.
Lasers Med Sci ; 39(1): 3, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38082158

RESUMO

Palladium nanoparticles (Pd NPs) show significant promise as agents for the photothermal treatment of tumors due to their high photothermal conversion efficiency and thermal stability. theoretical calculations were conducted to investigate the electric field and solid heat conduction of Pd NPs with various sizes and particle distances, aiming to achieve the maximum photothermal conversion efficiency during laser irradiation. Subsequently, Pd NPs with optimal size and structure were synthesized. In vitro and in vivo experiments were conducted to evaluate photothermal conversion. The theoretical results indicated that a peak temperature of 90.12 °C is achieved when the side length is 30 nm with a distance of 2 nm. In vitro experiments demonstrated that the photothermal conversion efficiency of Pd NPs can reach up to 61.9%. in vivo experiments revealed that injecting Pd NPs into blood vessels can effectively reduce the number of laser pulses by 22.22%, thereby inducing obvious vasoconstriction.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Humanos , Paládio/farmacologia , Paládio/química , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/química , Análise de Elementos Finitos , Nanopartículas/química , Neoplasias/terapia , Luz , Fototerapia/métodos , Linhagem Celular Tumoral
5.
Sci Rep ; 13(1): 16131, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752178

RESUMO

A systematic study is currently demonstrated approach for approving the superior role of silver and palladium metallic particles in acting the role of mordant with acquiring the dyed cotton fabrics excellence in color fastness with additional functions of antimicrobial potentiality and UV-protection action. Whereas, samples were dyed with extract of red peanuts skin as natural textile colorant (RPN dye). The represented data revealed that, in absence of mordant, the samples treated with metal precursors prior to dyeing were exhibited with the excellent color strength, color fastness, antimicrobial action and UV-protection action. Color fastness (washing, rubbing and light fastness) was estimated to be in the range of very good-excellent. Sample pretreated with silver salt and dyed in the absence of mordant was graded with excellent UV-protection action (UPF 31.5, UVB T% 2.6% and UVB blocking percent 97.4%). Antimicrobial potency against E. coli, S. aureus and Candida albicans through inhibition zone and the reduction percent was approved to be in the range of excellence (93.01-99.51%) for the samples dyed in absence of mordant and pretreated with either silver or palladium precursors.


Assuntos
Arachis , Prata , Corantes , Eritema , Escherichia coli , Gossypium , Paládio , Extratos Vegetais/farmacologia , Prata/farmacologia , Staphylococcus aureus , Têxteis
6.
ACS Appl Mater Interfaces ; 15(33): 39081-39098, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37566573

RESUMO

Recent developments in nanomaterials with programmable optical responses and their capacity to modulate the photothermal effect induced by an extrinsic source of light have elevated plasmonic photothermal therapy (PPTT) to the status of a favored treatment for a variety of malignancies. However, the low penetration depth of near-infrared-I (NIR-I) lights and the need to expose the human body to a high laser power density in PPTT have restricted its clinical translation for cancer therapy. Most nanostructures reported to date exhibit limited performance due to (i) activity only in the NIR-I region, (ii) the use of intense laser, (iii) need of large concentration of nanomaterials, or (iv) prolonged exposure times to achieve the optimal hyperthermia state for cancer phototherapy. To overcome these shortcomings in plasmonic nanomaterials, we report a bimetallic palladium nanocapsule (Pd Ncap)─with a solid gold bead as its core and a thin, perforated palladium shell─with extinction both in the NIR-I as well as the NIR-II region for PPTT applications toward cancer therapy. The Pd Ncap demonstrated exceptional photothermal stability with a photothermal conversion efficiency of ∼49% at the NIR-II (1064 nm) wavelength region at a very low laser power density of 0.5 W/cm2. The nanocapsules were further surface-functionalized with Herceptin (Pd Ncap-Her) to target the breast cancer cell line SK-BR-3 and exploited for in vitro PPTT applications using NIR-II light. Pd Ncap-Her caused more than 98% cell death at a concentration of just 50 µg/mL and a laser power density of 0.5 W/cm2 with an output power of only 100 mW. Flow cytometric and microscopic analyses revealed that Pd Ncap-Her-induced apoptosis in the treated cancer cells during PPTT. Additionally, Pd Ncaps were found to have reactive oxygen species (ROS) scavenging ability, which can potentially reduce the damage to cells or tissues from ROS produced during PPTT. Also, Pd Ncap demonstrated excellent in vivo biocompatibility and was highly efficient in photothermally ablating tumors in mice. With a high photothermal conversion and killing efficiency at very low nanoparticle concentrations and laser power densities, the current nanostructure can operate as an effective phototherapeutic agent for the treatment of different cancers with ROS-protecting ability.


Assuntos
Hipertermia Induzida , Nanocápsulas , Nanopartículas , Neoplasias , Humanos , Feminino , Animais , Camundongos , Fototerapia , Paládio/farmacologia , Paládio/química , Terapia Fototérmica , Espécies Reativas de Oxigênio , Neoplasias/terapia , Nanopartículas/química , Linhagem Celular Tumoral
7.
J Mater Chem B ; 11(33): 7942-7949, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37539820

RESUMO

Nanozymes are artificial enzymes that mimic natural enzyme-like activities and exhibit tremendous potential for tumor chemodynamic therapy. However, the development of novel nanozymes with superior catalytic activities for nanotheranostics remains a formidable challenge. Herein, we report a facile synthesis of monodisperse palladium nanosheets (Pd nanosheets) and their assembly on graphene oxide (GO) that enhances the catalytic activities of Pd nanoparticles. Simultaneously, the obtained nanocomposites (rGO-Pd) could be applied as a smart near-infrared (NIR) light-responsive nanotheranostic for near infrared imaging-guided chemodynamic/photothermal combined therapy. Notably, rGO-Pd exhibited high peroxidase mimicking activities, which could catalyze the conversion of intratumoral H2O2 to ˙OH. Impressively, the reactive oxygen species (ROS) generation of rGO-Pd was further remarkably enhanced by the endogenous acidity of the tumor microenvironment and the exogenous NIR light-responsive photothermal effect. These collective properties of the rGO-Pd nanozyme enabled it to be a ROS generation accelerator for photothermally enhanced tumor chemodynamic therapy. Thus, the as-developed rGO-Pd may represent a promising new type of high-performance nanozyme for multifunctional nanotheranostics toward cancer.


Assuntos
Melanoma , Fototerapia , Humanos , Fototerapia/métodos , Paládio/farmacologia , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Microambiente Tumoral
8.
BMC Palliat Care ; 22(1): 102, 2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37481524

RESUMO

BACKGROUND: In Palliative Care, actors from different professional backgrounds work together and exchange case-specific and expert knowledge and information. Since Palliative Care is traditionally distant from digitalization due to its holistically person-centered approach, there is a lack of suitable concepts enabling digitalization regarding multi-professional team processes. Yet, a digitalised information and collaboration environment geared to the requirements of palliative care and the needs of the members of the multi-professional team might facilitate communication and collaboration processes and improve information and knowledge flows. Taking this chance, the presented three-year project, PALLADiUM, aims to improve the effectiveness of Palliative Care teams by jointly sharing available inter-subjective knowledge and orientation-giving as well as action-guiding practical knowledge. Thus, PALLADiUM will explore the potentials and limitations of digitally supported communication and collaboration solutions. METHODS: PALLADiUM follows an open and iterative mixed methods approach. First, ethnographic methods - participant observations, interviews, and focus groups - aim to explore knowledge and information flow in investigating Palliative Care units as well as the requirements and barriers to digitalization. Second, to extend this body, the analysis of the historical hospital data provides quantitative insights. Condensing all findings results in a to-be work system. Adhering to the work systems transformation method, a technical prototype including artificial intelligence components will enhance the collaborative teamwork in the Palliative Care unit. DISCUSSION: PALLADiUM aims to deliver decisive new insights into the preconditions, processes, and success factors of the digitalization of a medical working environment as well as communication and collaboration processes in multi-professional teams. TRIAL REGISTRATION: The study was registered prospectively at DRKS (Deutsches Register Klinischer Studien) Registration-ID: DRKS0025356 Date of registration: 03.06.21.


Assuntos
Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Cuidados Paliativos , Humanos , Paládio , Inteligência Artificial , Projetos de Pesquisa
9.
BJS Open ; 7(3)2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37254902

RESUMO

INTRODUCTION: Pancreatic cancer has one of the worst prognoses of all cancers. Patients with locally advanced pancreatic cancer have a 12.7-20.2 per cent chance of receiving curative surgery after induction systemic chemotherapy. Intratumoral injection therapies have been studied as complementary treatment options for improved local tumour control. The aim of this systematic review was to provide an overview of intratumoral injection therapies, their safety, and oncological outcome in patients with locally advanced pancreatic cancer. METHODS: A literature search was conducted in PubMed, Embase and the Cochrane Library for articles written in English up to 28 November 2022. All study designs involving at least five patients with locally advanced pancreatic cancer who were treated with an intratumoral injection therapy were included. Critical appraisal of the included studies was performed using the Newcastle-Ottawa scale. RESULTS: After evaluation of the 1680 articles yielded by the systematic search, 52 studies treating 1843 patients were included. Included intratumoral injection treatment modalities comprised iodine-125 (125I) seed brachytherapy (32 studies, 1283 patients), phosphorus-32 (32P) microbrachytherapy (5 studies, 133 patients), palladium-103 (103Pd) seed brachytherapy (2 studies, 26 patients), immunotherapy (9 studies, 330 patients), and chemotherapy (4 studies, 71 patients). Overall survival ranged between 7.0 and 16.0 months for 125I, 5.2 and 15.5 months for 32P, 6.9 and 10.0 months for 103Pd, 5.8 and 13.8 months for immunotherapy, and 9.0 and 16.2 months for chemotherapy. Severe complication (greater than or equal to grade III complications using Clavien-Dindo classification) rates were 6.2 per cent for 125I, 49.2 per cent for 32P, 15 per cent for 103Pd, 57.9 per cent for immunotherapy, and 0 per cent for chemotherapy. CONCLUSION: Five intratumoral injection therapies are described and an overview is reported. Some intratumoral injection therapies for patients with locally advanced pancreatic cancer seem safe, although 32P microbrachytherapy and immunotherapy require additional evidence. Currently available data are insufficient to provide firm conclusions regarding the added value to survival. The potential advantage of intratumoral injection therapies complementary to conventional care should be studied in well designed RCTs.


Assuntos
Radioisótopos do Iodo , Neoplasias Pancreáticas , Humanos , Radioisótopos do Iodo/uso terapêutico , Paládio/uso terapêutico , Injeções Intralesionais , Neoplasias Pancreáticas/tratamento farmacológico
10.
Angew Chem Int Ed Engl ; 62(19): e202216822, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36917027

RESUMO

Pd-catalyzed chemistry has played a significant role in the growing subfield of bioorthogonal catalysis. However, rationally designing Pd nanocatalysts that show outstanding catalytic activity and good biocompatibility poses a great challenge. Herein, we propose an innovative strategy through exploiting black phosphorous nanosheets (BPNSs) to enhance Pd-mediated bioorthogonal catalytic activity. Firstly, the electron-donor properties of BPNSs enable in situ growth of Pd nanoparticles (PdNPs) on it. Meanwhile, due to the superb capability of reducing PdII , BPNSs can act as hard nucleophiles to accelerate the transmetallation in the decaging reaction process. Secondly, the lone pair electrons of BPNSs can firmly anchor PdNPs on their surface via Pd-P bonds. This design endows Pd/BP with the capability to retard tumor growth by activating prodrugs. This work proposes new insights into the design of heterogeneous transition-metal catalysts (TMCs) for bioorthogonal catalysis.


Assuntos
Nanopartículas , Neoplasias , Pró-Fármacos , Humanos , Paládio/química , Fósforo , Neoplasias/patologia , Catálise
11.
Analyst ; 148(9): 2064-2072, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36988972

RESUMO

We designed a simple, inexpensive, and user-friendly assay using mesoporous silica nanoparticles to detect analytes. Highly stable and uniform palladium nanoparticles covered with mesoporous silica (Pd@mSiO2) were generated and characterized extensively using physical methods. Human Serum Albumin (HSA) protein or ssDNA specific to the HIV gag region was capped onto the Pd@mSiO2 electrostatically. This "cap" prevented the Pd(0) inside the mesoporous silica nanoparticles from catalyzing the conversion of non-fluorescent molecules to fluorescent molecules. In the presence of target anti-HSA antibodies or complementary sequence (HIV gag), HSA protein or DNA cap dissociated from the surface of Pd@mSiO2-NH2 through the specific antigen-antibody reaction or DNA hybridization, allowing Pd(0) to convert the non-fluorescent molecules to fluorescent molecules. The limit and range of detection of anti-HSA antibodies were 3.8 nM and 3.8 nM to 133.3 nM, respectively. The limit and range of detection of HIV gag were 1.6 nM and 1.6 nM to 15 nM, respectively. This simple, inexpensive, "add sample and measure" diagnostic assay could potentially be incorporated into point of care diagnostics for low-resource settings.


Assuntos
Infecções por HIV , Nanopartículas Metálicas , Nanopartículas , Humanos , Paládio , Dióxido de Silício , DNA
12.
J Radiat Res ; 64(2): 369-378, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36702611

RESUMO

Auger-emitting radionuclides have potential application in targeted radiotherapy, particularly for metastatic cancers. This possibility, especially, is stemmed from their characteristic short-range (a few µm) in biological systems allowing localization of high dose within small tumours. To explore this potential application, a Geant4 Monte Carlo toolkit has been employed to simulate the energy deposition of different radionuclides in a water model. The Geant4 Monte Carlo toolkit has model packages to simulate the interaction of radiation with matter and with diverse applications such as studies in science and medicine. In this study, the Geant4-DNA package was used to simulate the radiolytic yields induced by some Auger electron-emitting (AE) radionuclides including; I-131, I-125 and Pd-103, In-111, Ru-97 and Rh-103 m in water model. The results showed that the transient yield of the radiolytic species is characterized by the kinetic energies of the emitted electrons. It was observed that almost all the radionuclides, except I-131, deposited more energy in their proximity thereby inducing a high density of spurs to interact in a short time. It is, therefore, important to consider the kinetic energies of the emitted particles in choosing a radionuclide for specified targeted radiotherapy. This means that apart from their toxicity, compatibility with chelator and carrier molecules, and method of production, we can predict radionuclides such as In-111, Ru-97, Pb-103 m and I-125 could be relevant for targeted radiotherapy for the treatment of metastasis lesions, or tiny tumours at the cellular level, and tumours after surgical resection.


Assuntos
Radioisótopos do Iodo , Neoplasias , Humanos , Elétrons , Paládio , Simulação por Computador , Água , Neoplasias/radioterapia , DNA , Método de Monte Carlo
13.
Sci Rep ; 13(1): 1272, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36690716

RESUMO

In this paper, a novel catalyst is introduced based on the immobilization of palladium onto magnetic Fucus Vesiculosus extract (Pd@mFuVe catalyst). For the synthesis of Pd@mFuVe catalyst, Fucus Vesiculosus extract is obtained from the plant source, followed by the synthesis of superparamagnetic iron oxide nanoparticles (SPION) onto the extract. The catalyst is characterized by several methods, including scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), FT-IR spectroscopy, vibrating sample magnetometer (VSM), powder X-ray diffraction analysis (XRD), and inductively coupled plasma (ICP). The activity of Pd@mFuVe catalyst is studied in the synthesis of N-alkyl-2-(4-methyl-1-oxoisoquinolin-2(1H)-yl)-2-phenylacetamides. The products were synthesized in three steps, the synthesis of 2-iodobenzoic acid from 2-aminobenzoic acid, which participated in a multicomponent reaction with allylamine, aldehydes, and isocyanides, followed by a cyclization reaction, catalyzed by Pd@mFuVe catalyst. The product yields are high and the catalyst showed good reusability after 5 sequential runs. The most significant, Pd@mFuVe catalyst is fabricated from a plant extract source as a green support for the catalyst.


Assuntos
Fucus , Paládio , Paládio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Catálise , Extratos Vegetais/química , Fenômenos Magnéticos
14.
Can J Ophthalmol ; 58(3): 262-269, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-34929184

RESUMO

OBJECTIVE: To investigate vascular and morphologic optic disc changes after slotted plaque radiation therapy for choroidal melanoma involving the optic disc. DESIGN: Retrospective cross-sectional study. PARTICIPANTS: Thirty-nine patients with choroidal melanoma involving the optic nerve. METHODS: Each melanoma was treated with palladium-103 slotted plaque brachytherapy (incorporating and/or surrounding the optic nerve sheath) between 2005 and 2019. Imaging of the optic nerve before and after radiation allowed for documentation and evaluation of optic nerve pallor and cup-to-disc ratio (CDR) changes. Optical coherence tomography (OCT) CDR measurements and intraocular pressure (IOP) were recorded pretreatment and at follow-up. Of these patients, 22 also had OCT angiography (OCT-A) images with sufficient quality for evaluation of blood vessel density and length. Differences in cup-to-disc measurements were correlated with changes in OCT-A-measured vessel density and length. RESULTS: Following slotted plaque radiation therapy, there was no significant increase in IOP or optic nerve pallor. OCT and colour photography revealed significant increases (both p < 0.001) in CDR from pretreatment to the last follow-up. Increased CDRs on OCT were significantly correlated to OCT-A-measured change in vessel length (p = 0.027). Similarly, increased CDR ratios on fundus photography were significantly correlated with OCT-A-measured change in vessel density (p = 0.043) and length (p = 0.019). CONCLUSION: Fundus photography and OCT measurements revealed increased optic disc cupping following slotted plaque radiation therapy. Cupping was associated with OCT-A evidence of synchronous progressive peripapillary vascular occlusion and attenuation. Therefore, slotted plaque radiation-induced peripapillary and papillary ischemia was associated with increased CDR ratios and optic disc cupping.


Assuntos
Braquiterapia , Melanoma , Disco Óptico , Humanos , Radioisótopos , Paládio , Braquiterapia/métodos , Estudos Retrospectivos , Estudos Transversais , Palidez , Pressão Intraocular , Melanoma/diagnóstico , Melanoma/radioterapia , Tomografia de Coerência Óptica/métodos
15.
Environ Res ; 220: 115153, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36574802

RESUMO

This study reports a versatile process for the fabrication of a microporous heterogeneous palladium nanocatalyst on a novel spherical, biodegradable, and chemically/physically resistant catalyst support consisting of chitosan (CS) and cigarette waste-derived activated carbon (CAC). The physicochemical properties of the microporous Pd-CS-CAC nanocatalyst developed were successfully determined by FTIR, XRD, FE-SEM, TEM, BET, and EDS techniques. TEM studies showed that the average particle size of the synthesized Pd NPs was about 30 nm. The catalytic prowess of microporous Pd-CS-CAC was evaluated in the reduction/decolorization of various nitroarenes (2-nitroaniline (2-NA), 4-nitroaniline (4-NA), 4-nitrophenol (4-NP), and 4-nitro-o-phenylenediamine (4-NPD)) and organic dyes (methyl red (MR), methyl orange (MO), methylene blue (MB), congo red (CR), and rhodamine B (RhB)) in an aqueous medium in the presence of NaBH4 as the reducing agent at room temperature. The catalytic activities were studied by UV-Vis absorption spectroscopy of the supernatant at regular time intervals. The short reaction times, mild reaction conditions, high efficiency (100% conversion), easy separation, and excellent chemical stability of the catalyst due to its heterogeneity and reusability are the advantages of this method. The results of the tests showed that reduction/decolorization reactions were successfully carried out within 10-140 s due to the good catalytic ability of Pd-CS-CAC. Moreover, Pd-CS-CAC was reused for 5 consecutive times with no loss of the initial shape, size, and morphology, confirming that it was a sustainable and robust nanocatalyst.


Assuntos
Quitosana , Paládio , Paládio/química , Quitosana/química , Corantes/química , Vermelho Congo/química , Extratos Vegetais/química , Catálise
16.
J Environ Sci (China) ; 126: 333-347, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36503761

RESUMO

Pd/Al2O3 catalysts supported on Al2O3 of different particle sizes were synthesized and applied in methane combustion. These catalysts were systematically characterized by Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), high resolution-transmission electron microscopy (HR-TEM), high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM), H2-temperature-programmed reduction (H2-TPR), O2-temperature-programmed oxidation (O2-TPO), X-ray photoelectron spectroscopy (XPS), and X-ray absorption fine structure (XAFS). The characterization results indicated that nano-sized Al2O3 enabled the uniform dispersion of palladium nanoparticles, thus contributing to the excellent catalytic performance of these nano-sized Pd/Al2O3 catalysts. Among them, Pd/Al2O3-nano-10 (Pd/Al2O3 supported by alumina with an average particle size of 10 nm) showed superior catalytic activity and stability for methane oxidation under harsh practical conditions. It maintained excellent catalytic performance for methane oxidation for 50 hr and remained stable even after harsh hydrothermal aging in 10 vol.% steam at 800°C for 16 hr. Characterization results revealed that the strong metal-support interactions and physical barriers provided by Al2O3-nano-10 suppressed the coalescence ripening of palladium species, and thus contributed to the superior sintering resistance of the Pd/Al2O3-nano-10 catalyst.


Assuntos
Nanopartículas Metálicas , Paládio , Óxido de Alumínio , Metano , Catálise
17.
Fitoterapia ; 164: 105353, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36402264

RESUMO

A ring distortion strategy was applied to the synthesis of a series of intramolecular cross-coupled analogues of forskolin 1. Treatment with palladium acetate, forskolin underwent an intramolecular cross-coupling reaction to generate a novel cycloalkene ether 2 in 85% yield. Under the same conditions, a series of forskolin ester analogues 4a-4d were prepared from 1-OH ester derivatives of forskolin 3a-3d in 85-93% yields. Treating cycloalkene ether 2 with aryl iodides in the presence of a palladium catalyst afforded Z-isomers arylation products 5a-5e in a stereoselective manner in 70-85% yields.


Assuntos
Cicloparafinas , Estrutura Molecular , Colforsina , Paládio , Ésteres , Éteres , Catálise
18.
Sci Total Environ ; 857(Pt 3): 159517, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36302403

RESUMO

Although numerous drugs are practiced to control malaria and its vectors, more recently, eco-friendly control tools have been proposed to battle its etiologic agents. Thus, using green bionanotechnology approaches, we aimed to synthesize palladium nanoparticles (Pd NPs) from the macroalgae Sargassum fusiforme (Sf), its potential antiparasitic activity against P. falciparum, as well as its possible cytotoxicity, in HeLa cells. After the biosynthesis of the PdSf NPs, their characterization was carried out by UV-Vis, FESEM, and EDX analyses, and their hydrodynamic size, zeta potential, and surface area were determined. Furthermore, the functional groups of the PdSf NPs were analyzed by FT-IR and GC-MS. While PdSf NPs had an IC50 of 7.68 µg/mL (Chloroquine (CQ)-s) and 16.42 µg/mL, S. fusiforme extract had an IC50 of 14.38 µg/mL (CQ-s) and 35.27 µg/mL (CQ-r). With an IC50 value of 94.49 µg/mL, PdSf NPs exhibited the least toxic effect on the HeLa cells. The Lipinski rule of five and ADMET prediction were used to assess the in silico models of caffeine acid hexoside and quercetin 7-O-hexoside for the presence of drug-like properties. Pathogenic proteins, primarily responsible for motility, binding, and disease-causing, were the target of the structurally based docking studies between plant-derived compounds and pathogenic proteins. Thus, our study pioneered promising results that support the potential antiplasmodial activity of eco-friendly synthesized PdSf NPs using S. fusiforme extract against P. falciparum, opening perspectives for further exploration into the use of these NPs in malaria therapy.


Assuntos
Anopheles , Malária , Nanopartículas Metálicas , Sargassum , Alga Marinha , Animais , Humanos , Plasmodium falciparum , Paládio , Anopheles/parasitologia , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Alga Marinha/química , Células HeLa , Espectroscopia de Infravermelho com Transformada de Fourier , Larva , Mosquitos Vetores , Extratos Vegetais/química
19.
Anal Chim Acta ; 1232: 340470, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36257744

RESUMO

A novel ultrasensitive electrochemical aptasensor was proposed for quantitative detection of Cd2+. To this end, flower-like polyethyleneimine-functionalized molybdenum disulfide-supported gold nanoparticles (PEI-MoS2 NFs@Au NPs) were used as substrates for the modification of bare gold electrodes (AuE). PEI-MoS2 NFs@Au NPs not only possessed excellent biocompatibility and large specific surface area to enhance the cDNA loading capacity, but also possessed good conductivity to accelerate the electron transfer rate. Furthermore, the preparation of dendritic platinum-palladium nanoparticles (PtPd NPs) can effectively load Cd2+-aptamer. Thionine and aptamers were loaded onto PtPd NPs to construct Thi-PtPd NPs-aptamer signal probes. The signal probes were captured by the cDNA immobilized on the electrode via base-pairing rule, and the signal of Thi was detected by differential pulse voltammetry (DPV). In the presence of Cd2+, aptamer-cDNA unwinded, and the combination of aptamer and Cd2+ caused the signal probes to fall off the electrode and the electrical signal decreases. Under optimal conditions, the proposed aptasensor exhibited a linear relationship between the logarithm of Cd2+ concentration and the current response over a wide range of 1 × 10-3 nM to 1 × 102 nM, with a detection limit of 2.34 × 10-4 nM. At the same time, the aptasensor was used to detect Cd2+ in tap water with satisfactory results. In addition, it has good reproducibility, selectivity and stability, and has broad application prospects in heavy metal analysis.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Nanocompostos , Platina , Ouro , Cádmio , Paládio , Molibdênio , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Polietilenoimina , DNA Complementar , Reprodutibilidade dos Testes , Água , Limite de Detecção
20.
Food Chem Toxicol ; 169: 113406, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36067880

RESUMO

Nanotechnology is an interdisciplinary study that has been developing worldwide in recent years and has a serious impact on human life. The fact that the nanoparticles of plant origin are clean, non-toxic, and biocompatible has enabled new fields of study. The Hibiscus sabdariffa (H. sabdariffa) plant has been attracted by scientists because of its impact on health and many other areas. The lipid peroxidation inhibiting activity, antioxidant properties, and antimicrobial properties of H. sabdariffa plant with Ag-Pd metal was ditermined. For the total phenolic component, gallic acid was used as the standard and quarcetin was used for the total flavonoid. The lipid peroxidation inhibition activity of Ag-Pd NPs in ethanol extract was found to be very well compared to the positive control (BHA). The lowest and highest concentrations of DPPH radical scavenging activity were 82.178-97.357%, whereas for BHA these values were found to be 84.142-94.142%. The highest concentration of Ag-Pd NPs at 200 µg/mL the DPPH radical quenching activity was higher than BHA. Ag-Pd NPs showed a good antimicrobial activity against certain pathogenic microorganisms such as Bacillus subtilis, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, which are the causative agents of various diseases in humans. The photodegradation activity of Ag-Pd NPs also investigated against Methyl orange dye (MO) under sunlight irradiation for 120 min and was found to be as 67.88.


Assuntos
Antibacterianos , Anti-Infecciosos , Peroxidação de Lipídeos , Nanopartículas Metálicas , Paládio , Fotólise , Extratos Vegetais , Prata , Humanos , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Hidroxianisol Butilado , Escherichia coli/efeitos dos fármacos , Etanol/química , Flavonoides/química , Flavonoides/farmacologia , Ácido Gálico/química , Ácido Gálico/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Paládio/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Prata/química
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