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1.
Adv Mater ; 36(29): e2400307, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38657273

RESUMO

The advancement of message RNA (mRNA) -based immunotherapies for cancer is highly dependent on the effective delivery of RNA (Ribonucleic) payloads using ionizable lipid nanoparticles (LNPs). However, the clinical application of these therapies is hindered by variable mRNA expression among different cancer types and the risk of systemic toxicity. The transient expression profile of mRNA further complicates this issue, necessitating frequent dosing and thus increasing the potential for adverse effects. Addressing these challenges, a high-throughput combinatorial method is utilized to synthesize and screen LNPs that efficiently deliver circular RNA (circRNA) to lung tumors. The lead LNP, H1L1A1B3, demonstrates a fourfold increase in circRNA transfection efficiency in lung cancer cells over ALC-0315, the industry-standard LNPs, while providing potent immune activation. A single intratumoral injection of H1L1A1B3 LNPs, loaded with circRNA encoding interleukin-12 (IL-12), induces a robust immune response in a Lewis lung carcinoma model, leading to marked tumor regression. Immunological profiling of treated tumors reveals substantial increments in CD45+ leukocytes and enhances infiltration of CD8+ T cells, underscoring the ability of H1L1A1B3 LNPs to modulate the tumor microenvironment favorably. These results highlight the potential of tailored LNP platforms to advance RNA drug delivery for cancer therapy, broadening the prospects for RNA immunotherapeutics.


Assuntos
Imunoterapia , Interleucina-12 , Lipídeos , Neoplasias Pulmonares , Nanopartículas , RNA Circular , Interleucina-12/genética , Interleucina-12/metabolismo , Imunoterapia/métodos , RNA Circular/genética , Animais , Neoplasias Pulmonares/terapia , Nanopartículas/química , Camundongos , Linhagem Celular Tumoral , Humanos , Lipídeos/química , RNA/química , Camundongos Endogâmicos C57BL
2.
Nanomaterials (Basel) ; 13(19)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37836371

RESUMO

Cu3SbSe4 is a potential p-type thermoelectric material, distinguished by its earth-abundant, inexpensive, innocuous, and environmentally friendly components. Nonetheless, the thermoelectric performance is poor and remains subpar. Herein, the electrical and thermal transport properties of Cu3SbSe4 were synergistically optimized by S alloying. Firstly, S alloying widened the band gap, effectively alleviating the bipolar effect. Additionally, the substitution of S in the lattice significantly increased the carrier effective mass, leading to a large Seebeck coefficient of ~730 µVK-1. Moreover, S alloying yielded point defect and Umklapp scattering to significantly depress the lattice thermal conductivity, and thus brought about an ultralow κlat ~0.50 Wm-1K-1 at 673 K in the solid solution. Consequently, multiple effects induced by S alloying enhanced the thermoelectric performance of the Cu3SbSe4-Cu3SbS4 solid solution, resulting in a maximum ZT value of ~0.72 at 673 K for the Cu3SbSe2.8S1.2 sample, which was ~44% higher than that of pristine Cu3SbSe4. This work offers direction on improving the comprehensive TE in solid solutions via elemental alloying.

3.
Nano Lett ; 22(24): 10040-10048, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36521033

RESUMO

Inspired by the natural phenomenon of phenolic-protein interactions, we translate this "naturally evolved interaction" to a "phenolic acid derivative based albumin bound" technology, through the synthesis of phenolic acid derivatives comprising a therapeutic cargo linked to a phenolic motif. Phenolic acid derivatives can bind to albumin and form nanocomplexes after microfluidic mixing. This strategy has been successfully applied to different types of anticancer drugs, including taxanes, anthraquinones, etoposides, and terpenoids. Paclitaxel was selected as a model drug for an in-depth study. Three novel paclitaxel-phenolic acid conjugates have been synthesized. Molecular dynamics simulations provide insights into the self-assembled mechanisms of phenolic-protein nanocomplexes. The nanocomplexes show improved pharmacokinetics, elevated tolerability, decreased neurotoxicity, and enhanced anticancer efficacies in multiple murine xenograft models of breast cancer, in comparison with two clinically approved formulations, Taxol (polyoxyethylated castor oil-formulated paclitaxel) and Abraxane (nab-paclitaxel). Such a robust system provides a broadly applicable platform for the development of albumin-based nanomedicines and has great potential for clinical translation.


Assuntos
Neoplasias da Mama , Nanopartículas , Humanos , Animais , Camundongos , Feminino , Albumina Sérica Humana , Paclitaxel/uso terapêutico , Paclitaxel/farmacocinética , Albuminas/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Nanopartículas/uso terapêutico
4.
Adv Sci (Weinh) ; 9(27): e2202744, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35896947

RESUMO

Spatiotemporal delivery of nanoparticles (NPs) at the "cellular level" is critical for nanomedicine, which is expected to deliver as much cytotoxic drug into cancer cells as possible when NPs accumulate in tumors. However, macrophages and cancer-associated fibroblasts (CAFs) that are present within tumors limit the efficiency of spatiotemporal delivery. To overcome this limitation, glutathion pulse therapy is designed to promote reduction-sensitive Larotaxel (LTX) prodrug NPs to escape the phagocytosis of macrophages and penetrate through the stromal barrier established by CAFs in the murine triple negative breast cancer model. This therapy improves the penetration of NPs in tumor tissues as well as the accumulation of LTX in cancer cells, and remodels the immunosuppressive microenvironment to synergize PD-1 blockade therapy. More importantly, a method is established that can directly observe the biodistribution of NPs between different cells in vivo to accurately quantify the target drugs accumulated in these cells, thereby advancing the spatiotemporal delivery research of NPs at the "cellular level."


Assuntos
Nanopartículas , Neoplasias , Pró-Fármacos , Animais , Glutationa/uso terapêutico , Humanos , Camundongos , Pró-Fármacos/uso terapêutico , Receptor de Morte Celular Programada 1 , Taxoides , Distribuição Tecidual , Microambiente Tumoral
5.
Acta Pharm Sin B ; 12(3): 1163-1185, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35530162

RESUMO

Cancer immunotherapy has become a new generation of anti-tumor treatment, but its indications still focus on several types of tumors that are sensitive to the immune system. Therefore, effective strategies that can expand its indications and enhance its efficiency become the key element for the further development of cancer immunotherapy. Natural products are reported to have this effect on cancer immunotherapy, including cancer vaccines, immune-check points inhibitors, and adoptive immune-cells therapy. And the mechanism of that is mainly attributed to the remodeling of the tumor-immunosuppressive microenvironment, which is the key factor that assists tumor to avoid the recognition and attack from immune system and cancer immunotherapy. Therefore, this review summarizes and concludes the natural products that reportedly improve cancer immunotherapy and investigates the mechanism. And we found that saponins, polysaccharides, and flavonoids are mainly three categories of natural products, which reflected significant effects combined with cancer immunotherapy through reversing the tumor-immunosuppressive microenvironment. Besides, this review also collected the studies about nano-technology used to improve the disadvantages of natural products. All of these studies showed the great potential of natural products in cancer immunotherapy.

6.
Carbohydr Polym ; 289: 119437, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35483850

RESUMO

Diabetic skin ulcer is one of the most severe complications in diabetes, however, current therapeutic approaches are not effective enough. Agents modulating oxidative stress, inflammation, and angiogenesis are quite promising for alleviation of diabetic skin ulcers. In this study, a novel Sargassum kjellmanianum-derived polysaccharide (SARP) was prepared. SARP was an alginate with Mw of 45.4 kDa, consisting of 76.56% mannuronic acid, 18.89% guluronic acid, and 4.55% glucuronic acid. SARP could attenuate oxidative stress-induced cell damage via activating nuclear factor erythroid 2-related factor 2 (Nrf2). SARP also promoted the migration and tube formation of HUVECs, which was related to the increased vascular endothelial growth factor (VEGF) expression. In diabetic wound model, SARP (iv, 200 mg/kg) administration increased angiogenesis, alleviated oxidative stress, ameliorated diabetes-related aberrations, and thereby accelerated diabetic wound healing. These findings identified SARP had potential to be developed as a drug candidate for diabetic skin ulcers.


Assuntos
Complicações do Diabetes , Diabetes Mellitus Experimental , Sargassum , Alga Marinha , Úlcera Cutânea , Alginatos/farmacologia , Alginatos/uso terapêutico , Animais , Diabetes Mellitus Experimental/metabolismo , Neovascularização Patológica/tratamento farmacológico , Estresse Oxidativo , Sargassum/metabolismo , Alga Marinha/metabolismo , Úlcera Cutânea/complicações , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização
7.
Mar Drugs ; 19(11)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34822512

RESUMO

Angiogenesis, including the growth of new capillary blood vessels from existing ones and the malignant tumors cells formed vasculogenic mimicry, is quite important for the tumor metastasis. Anti-angiogenesis is one of the significant therapies in tumor treatment, while the clinical angiogenesis inhibitors usually exhibit endothelial cells dysfunction and drug resistance. Bis(2,3,6-tribromo-4,5-dihydroxybenzyl)ether (BTDE), a marine algae-derived bromophenol compound, has shown various biological activities, however, its anti-angiogenesis function remains unknown. The present study illustrated that BTDE had anti-angiogenesis effect in vitro through inhibiting human umbilical vein endothelial cells migration, invasion, tube formation, and the activity of matrix metalloproteinases 9 (MMP9), and in vivo BTDE also blocked intersegmental vessel formation in zebrafish embryos. Moreover, BTDE inhibited the migration, invasion, and vasculogenic mimicry formation of lung cancer cell A549. All these results indicated that BTDE could be used as a potential candidate in anti-angiogenesis for the treatment of cancer.


Assuntos
Inibidores da Angiogênese/farmacologia , Microalgas , Fenóis/farmacologia , Células A549/efeitos dos fármacos , Inibidores da Angiogênese/química , Animais , Organismos Aquáticos , Proliferação de Células/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Neovascularização Fisiológica/efeitos dos fármacos , Fenóis/química
8.
Mar Drugs ; 18(8)2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32759739

RESUMO

Marine algae contain various bromophenols that have been shown to possess a variety of biological activities, including antiradical, antimicrobial, anticancer, antidiabetic, anti-inflammatory effects, and so on. Here, we briefly review the recent progress of these marine algae biomaterials and their derivatives from 2011 to 2020, with respect to structure, bioactivities, and their potential application as pharmaceuticals.


Assuntos
Clorófitas , Cianobactérias , Hidrocarbonetos Bromados/farmacologia , Phaeophyceae , Fenóis/farmacologia , Rodófitas , Animais , Clorófitas/química , Cianobactérias/química , Humanos , Hidrocarbonetos Bromados/química , Hidrocarbonetos Bromados/isolamento & purificação , Estrutura Molecular , Phaeophyceae/química , Fenóis/química , Fenóis/isolamento & purificação , Rodófitas/química , Relação Estrutura-Atividade
9.
RSC Adv ; 10(32): 18753-18759, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35518304

RESUMO

In this paper, we report on the transport and magnetic properties of layered oxytelluride BiCuTeO polycrystals with slight mixed valence of Cu. The temperature-dependent electrical resistivity reveals degenerate semiconductor behavior (similar to metals). Under the action of an external magnetic field, the BiCuTeO polycrystal sample exhibits unsaturated magnetic resistance (MR) of about 8% at 2 K and 9 Tesla. The Hall resistivities show nonlinear behavior, suggesting the coexistence of both electrons and holes in the sample. When the temperature is decreased to around 110 K, the dominant carriers are changed from electrons to holes from the viewpoint of electrical transport, which is supported by the calculated temperature-dependent Fermi energy. Meanwhile, at low temperatures (<100 K), the impurity magnetic moment formed by a small amount of positive divalent copper exhibits short-range magnetism (a spin-glass-like feature), which gives rise to a narrow magnetic hysteresis loop. Our work may benefit in-depth understanding of physical properties of BiCuTeO-based materials.

10.
J Asian Nat Prod Res ; 22(9): 839-849, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31364407

RESUMO

The synergistic anti-tumor effect of schisandrin B (Sch.B) and apatinib was investigated in vitro. The CCK-8 assay revealed that Sch.B enhanced the inhibition of apatinib on cell proliferation by arresting cell cycle in G0/G1 phase. Sch.B also potentiated the suppression of apatinib on cell migration and invasion, by means of wound-healing and transwell invasion assay. Flow cytometry results showed that Sch.B enhanced apoptosis induced by apatinib. The results were confirmed by western blot analysis of the proteins MMP-9, and Bax caspase-9, and -12. These results suggest that combining apatinib and Sch.B is an effective therapeutic strategy for preventing GC progression. [Formula: see text].


Assuntos
Apoptose , Ciclo-Octanos , Linhagem Celular Tumoral , Proliferação de Células , Lignanas , Estrutura Molecular , Compostos Policíclicos , Piridinas
11.
Materials (Basel) ; 12(4)2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30823529

RESUMO

Emission of hazardous trace elements, especially arsenic from fossil fuel combustion, have become a major concern. Under an oxidizing atmosphere, most of the arsenic converts to gaseous As2O3. CaO has been proven effective in capturing As2O3. In this study, the mechanisms of As2O3 adsorption on CaO surface under O2 atmosphere were investigated by density functional theory (DFT) calculation. Stable physisorption and chemisorption structures and related reaction paths are determined; arsenite (AsO33-) is proven to be the form of adsorption products. Under the O2 atmosphere, the adsorption product is arsenate (AsO43-), while tricalcium orthoarsenate (Ca3As2O8) and dicalcium pyroarsenate (Ca2As2O7) are formed according to different adsorption structures.

12.
Phytomedicine ; 52: 264-271, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30599907

RESUMO

BACKGROUND: Puerarin, derived from a traditional Chinese herb Pueraria lobata (Willd.) Ohwi which was distributed globally and planted in most parts of China, has been extensively applied in patients with cardiovascular diseases in China. Yet a considerable proportion of the patients were accompanied with liver illnesses simultaneously because of all sorts of reasons. HYPOTHESIS/PURPOSE: It had been implied by some previous research that the absorption and the metabolism of puerarin were susceptible to liver issues due to changed P-gp and Ugt1a level, but pharmacokinetics of puerarin under such conditions were few concerned. Our study aimed to make sure whether and how much the behavior of puerarin in vivo was affected by hepatic diseases, and to explore the potential mechanisms. METHODS: A CCl4 induced rat model of hepatic fibrosis (HF) was prepared and verified. Single low/high doses of oral and intravenous administration of puerarin to HF and normal rats were performed. Pharmacokinetics of puerarin were determined by a validated HPLC method. The expression of P-gp, Ugt1a1, and Ugt1a7 in both liver and intestines were determined by quantitative RT-PCR and Western blot analysis respectively. RESULTS: The systemic exposure of puerarin in HF rats of experimental groups were found decreased remarkably except for that of the high dose intravenous group. Moreover, the expression of P-gp, Ugt1a1, and Ugt1a7 in liver and intestines of HF rats were figured out increased. CONCLUSION: The results indicated that the HF originated overexpression of Ugt1a1, Ugt1a7, and P-gp level played important roles in pharmacokinetics of puerarin, suggested the clinical regimen of puerarin based on normal populations might be inappropriate for patients with chronic liver diseases. It was implied drugs whose absorption or elimination were related to P-gp, Ugt1a1, or Ugt1a7 might also be affected by hepatic illnesses.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Glucuronosiltransferase/metabolismo , Isoflavonas/farmacocinética , Cirrose Hepática/tratamento farmacológico , Animais , Medicamentos de Ervas Chinesas/farmacologia , Masculino , Plantas Medicinais/química , Pueraria/química , Ratos , Ratos Sprague-Dawley
13.
Molecules ; 23(11)2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-30404182

RESUMO

Osimertinib, a new-generation inhibitor of the epidermal growth factor, has been used for the clinical treatment of advanced T790M mutation-positive tumors. In this research, an original analysis method was established for the quantification of osimertinib by ultra-performance liquid chromatography with time of flight mass spectrometry (UPLC-TOF-MS) in rat plasma. After protein precipitation with acetonitrile and sorafinib (internal standard, IS), they were chromatographed through a Waters XTerra MS C18 column. The mobile phase was acetonitrile and water (including 0.1% ammonia). The relative standard deviation (RSD) of the intra- and inter-day results ranged from 5.38 to 9.76% and from 6.02 to 9.46%, respectively, and the extraction recovery and matrix effects were calculated to range from 84.31 to 96.14% and from 91.46 to 97.18%, respectively. The results illustrated that the analysis method had sufficient specificity, accuracy and precision. Meanwhile, the UPLC-TOF-MS method for osimertinib was successfully applied into the pharmacokinetics of SD rats.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Piperazinas/sangue , Acrilamidas , Compostos de Anilina , Animais , Masculino , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
14.
Molecules ; 23(6)2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29925761

RESUMO

Puerarin is an isoflavonoid extracted from Pueraria lobata roots, and displays a broad range of pharmacological activities, including antidiabetic activity. However, information about the pharmacokinetics of puerarin in diabetics is scarce. This study was conducted to investigate the difference in pharmacokinetic effects of puerarin in normal rats and rats with diabetes mellitus (DM), and the mechanism involved. DM was induced by a combined high-fat diet (HFD) and streptozotocin (STZ) injection. Plasma concentrations of puerarin in DM, HFD, and control rats were determined after intravenous (20 mg/kg) and oral administration (500 mg/kg) of puerarin, and pharmacokinetic parameters were estimated. The messenger RNA (mRNA) and protein expression levels of Ugt1a1 and Ugt1a7 in rat livers and intestines were measured using qRT-PCR and western blot, respectively. The area under the concentration⁻time curve and the clearance of puerarin in the DM rats statistically differed from those in the control rats (p <0.05) with both administration routes. The hepatic and intestinal gene and protein expressions of Ugt1a1 and Ugt1a7 were significantly increased in the DM rats (p <0.05). Therefore, the metabolic changes in diabetes could alter the pharmacokinetics of puerarin. This change could be caused by upregulated uridine diphosphate (UDP)-glucuronosyltransferase activity, which may enhance puerarin clearance, and alter its therapeutic effects.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Glucuronosiltransferase/metabolismo , Hipoglicemiantes/farmacocinética , Isoflavonas/farmacocinética , Extratos Vegetais/farmacocinética , Administração Intravenosa , Administração Oral , Animais , Descoberta de Drogas , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/química , Isoflavonas/administração & dosagem , Isoflavonas/química , Masculino , Microssomos Hepáticos/metabolismo , Extratos Vegetais/química , Raízes de Plantas/química , Ratos , Ratos Sprague-Dawley , Traqueófitas/química , Regulação para Cima , Difosfato de Uridina/metabolismo
15.
Molecules ; 23(5)2018 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-29783787

RESUMO

Canagliflozin is a novel, orally selective inhibitor of sodium-dependent glucose co-transporter-2 (SGLT2) for the treatment of patients with type 2 diabetes mellitus. In this study, a sensitive and efficient UPLC-MS/MS method for the quantification of canagliflozin and its metabolites in rat plasma was established and applied to pharmacokinetics in a type 2 diabetic rat model. We firstly investigated the pharmacokinetic changes of canagliflozin and its metabolites in type 2 diabetic rats in order to use canagliflozin more safely, reasonably and effectively. We identified three types of O-glucuronide metabolites (M5, M7 and M17), two kinds of oxidation metabolites (M8 and M9) and one oxidation and glucuronide metabolite (M16) using API 5600 triple-TOF-MS/MS. Following liquid⁻liquid extraction by tert-butyl methyl ether, chromatographic separation of canagliflozin and its metabolites were performed on a Waters XBridge BEH C18 column (100 × 2.1 mm, 2.5 µm) using 0.1% acetonitrile⁻formic acid (75:15, v/v) as the mobile phase at a flow rate of 0.7 mL/min. Selected ion monitoring transitions of m/z 462.00→191.10, 451.20→153.10, 638.10→191.10 and 478.00→267.00 were chosen to quantify canagliflozin, empagliflozin (IS), O-glucuronide metabolites (M5, M7 and M17), and oxidation metabolites (M9) using an API 5500-triple-MS/MS in the positive electrospray ionization mode. The validation of the method was found to be of sufficient specificity, accuracy and precision. The pathological condition of diabetes could result in altered pharmacokinetic behaviors of canagliflozin and its metabolites. The pharmacokinetic parameters (AUC0⁻t, AUC0⁻∞, CLz/F, and Vz/F) of canagliflozin were significantly different between the CTRL and DM group rats (p < 0.05 or p < 0.01), which may subsequently cause different therapeutic effects.


Assuntos
Canagliflozina/farmacocinética , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Tipo 2/sangue , Hipoglicemiantes/farmacocinética , Administração Oral , Animais , Canagliflozina/administração & dosagem , Canagliflozina/sangue , Canagliflozina/química , Cromatografia Líquida de Alta Pressão/métodos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/sangue , Hipoglicemiantes/química , Limite de Detecção , Masculino , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Estreptozocina , Espectrometria de Massas em Tandem/métodos
16.
Inorg Chem ; 57(5): 2730-2735, 2018 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-29446937

RESUMO

The triangular lattice Na xRhO2 contains a 4d Rh element with large spin-orbit coupling, and the electron-electron correlation effect is expected to have some novel physical properties. Here we report NaRhO2 crystal growth by Na2CO3 vapor growth and a series of Na xRhO2 (0.25 ≤ x ≤ 1) crystals prepared using the chemical desodiation method. Na xRhO2 reveals a layer structure with the space group R3̅ m, and the lattice parameter a evolves from 3.09 to 3.03 Å and c from 15.54 to 15.62 Å when x decreases from 1.0 to 0.2. Decreasing potassium concentration leads to a contraction of the RhO6 octahedral layers, which may be attributed to a higher covalency of Rh-O bonds. More important, the metal-insulator transition in Na xRhO2 was observed in resistivity along the ab plane. The conducting mechanism of Na xRhO2 is strongly dependent on x. Two-dimensional variable range hopping (VRH) mechanisms (0.67 ≤ x ≤ 1) and metallic behaviors (0.42 and 0.47) are observed in temperature-dependent resistivity. The origin of this metal-insulator transition was discussed on the basis of the Ioffe-Regel criterion. Our work demonstrates the strong correlation between sodium concentration and physical properties of Na xRhO2.

17.
Sci Rep ; 7: 44587, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28294191

RESUMO

Transition metal dichalcogenides (TMDs) WTe2 and MoTe2 with orthorhombic Td phase, being potential candidates as type-II Weyl semimetals, are attracted much attention recently. Here we synthesized a series of miscible Mo1-xWxTe2 single crystals by bromine vapor transport method. Composition-dependent X-ray diffraction and Raman spectroscopy, as well as composition and temperature-dependent resistivity prove that the tunable crystal structure (from hexagonal (2H), monoclinic (ß) to orthorhombic (Td) phase) can be realized by increasing W content in Mo1-xWxTe2. Simultaneously the electrical property gradually evolves from semiconductor to semimetal behavior. Temperature-dependent Raman spectroscopy proves that temperature also can induce the structural phase transition from ß to Td phase in Mo1-xWxTe2 crystals. Based on aforementioned characterizations, we map out the temperature and composition dependent phase diagram of Mo1-xWxTe2 system. In addition, a series of electrical parameters, such as carrier type, carrier concentration and mobility, have also been presented. This work offers a scheme to accurately control structural phase in Mo1-xWxTe2 system, which can be used to explore type-II Weyl semimetal, as well as temperature/composition controlled topological phase transition therein.

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