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1.
Chemistry ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31489999

RESUMO

A divergent strategy for the facile preparation of various enantioenriched phenylthio-substituted lactones was developed based on Lewis base/Brønsted acid co-catalyzed thiolation of homoallylic acids. The acid-controlled regiodivergent cyclization (6-endo vs 5-exo) and acid-mediated stereoselective rearrangement of phenylthio-substituted lactones were explored. Experimental and computational studies were performed to clarify the origins of the regioselectivity and enantioselectivity. The calculation results suggest that C-O and C-S bond formation might occur simultaneously, without formation of a commonly supposed catalyst-coordianted thiiranium ion intermediate and the potential π-π stacking between substrate and SPh as an important factor in the enantiodetermining step. Finally, this methodology was applied in the rapid syntheses of bioactive natural products (+)-ricciocarpin A and (R)-dodecan-4-olide.

2.
Eur J Pharm Sci ; : 105058, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31472255

RESUMO

The biofilm formation of Pseudomonas aeruginosa (P. aeruginosa) is regulated by a phenomenon of quorum sensing (QS). With 5-hydroxyl-3,4-halogenated-5H-furan-2-ones as beginning, analogs bearing alkyl chains, vinyl bromide, or aromatic rings were designed and synthesized. The minimum inhibitory concentration (MIC) of the compounds against P. aeruginosa was assayed and the biofilm inhibition ratio was determined at different concentrations lower than the MIC. C-5 aromatic substituted furanones showed remarkable biofilm formation as well as inhibition of virulence factor production in P. aeruginosa. Fluorescence report analysis identified the QS regulatory mechanism of the most active compound 29. This study provides us a novel candidate for combating drug resistant bacteria strains by merely inhibiting biofilm formation. Without suppressing the regular life cycle of the bacteria, bacterial resistance mechanisms may not be activated.

3.
Cell Cycle ; : 1-14, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478454

RESUMO

Myotubularin related protein 7 (MTMR7), a key member of the MTMR family, depicts phosphatase activity and is involved in myogenesis and tumor growth. We have previously identified MTMR7 in the proteomic profile of mouse spermatogonial stem cell (SSC) maturation and differentiation, implying that MTMR7 is associated with neonatal testicular development. In this study, to further explore the distribution and function of MTMR7 in mouse testis, we studied the effect of Mtmr7 knockdown on neonatal testicular development by testicular and SSC culture methods. Our results revealed that MTMR7 is exclusively located in early germ cells. Deficiency of MTMR7 by morpholino in neonatal testis caused excessive SSC proliferation, which was attributable to the aberrant PI3K/AKT signaling activation. Altogether, our study demonstrates that MTMR7 maintains SSC homeostasis by inhibiting PI3K/AKT signaling activation.

5.
Int J Nanomedicine ; 14: 6179-6195, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31447559

RESUMO

Background and purpose: Gambogic acid (GA) is a natural compound that exhibited a promising multi-target antitumor activity against several types of cancer. However, the clinical application of this drug is limited due to its poor solubility and low tumor cell-specific delivery. In this study, the monomeric and dimeric Cyclo (Arg-Gly-Asp) c(RGD) tumor targeting peptides (c(RGDfK) and E-[c(RGDfK)2]) were used to modify GA loaded nanostructured lipid carriers (NLC) to reduce the limitations associated with GA and improve its antitumor activity. Methods: GA-NLC was prepared by emulsification and solvent evaporation methods and the surface of the NLC was conjugated with the c(RGD) peptides via an amide bond. The formulations were characterized for particle size, morphology and zeta potential, encapsulation efficiency and drug loading. The in-vitro cytotoxicity and cell uptake studies were conducted using 4T1 cell. Furthermore, the in-vivo antitumor activity and bio-distribution study were performed on female BALB/c nude mice. Results: The c(RGD) peptides modified GA-NLC was successfully prepared with the particles size about 20 nm. The HPLC analysis, FT-IR and 1H-NMR spectra confirmed the successful conjugation of the peptides with the NLC. The in-vitro cytotoxicity study on 4T1 cells revealed that c(RGD) peptides modified GA-NLCs showed significantly higher cytotoxicity at 0.25 and 0.5 µg/mL as compared to unmodified GA-NLC. Furthermore, the cell uptake study demonstrated that better accumulation of E-[c(RGDfK)2] peptides modified NLC in 4T1 cell after 12 h incubation. Moreover, the in-vivo study showed that c(RGD)s functionalized GA-NLC exhibited better accumulation in tumor tissue and tumor growth inhibition. In contrast to the monomeric c(RGD) peptide, the dimeric c(RGD) peptide (E-[c(RGDfK)2]) conjugated GA-NLC showed the improved antitumor activity and tumor targeting ability of GA-NLC. Conclusion: These data provide further support for the potential clinical applications of E-[c(RGDfK)2]-GA-NLC in breast cancer therapy.

6.
Pest Manag Sci ; 2019 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-31444936

RESUMO

BACKGROUND: To enhance discovering efficiency of new herbicidal compounds, a strategy for rapidly screening out strongly herbicidal chemical components from natural resources is necessary. RESULTS: Seventeen essential oils selected from 14 Eucalyptus species and hybrids were evaluated for their herbicidal activities on annual ryegrass. A feasible strategy was established for rapidly pinpointing the chemicals contributing to strong herbicidal activities without the process of isolation and purification of individual compounds. This strategy was based on gas chromatography-mass spectrometry (GC-MS) coupled with principal component analysis (PCA) and verified by the bioassay results using several individual compounds. Two strong herbicidal compounds trans-pinocarveol and α-terpineol were screened out using the strategy. The strong herbicidal activity of trans-pinocarveol was discovered for the first time. CONCLUSION: The established strategy of screening herbicidal compounds from natural resources is simple, feasible and reliable. This article is protected by copyright. All rights reserved.

7.
Bioresour Technol ; 291: 121860, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31374414

RESUMO

This study aims to enhance the quality of biofuel through microwave torrefaction pretreatment for lignin. Low density polyethylene (LDPE) was added as a hydrogen source during microwave co-pyrolysis along with the microwave-torrefied lignin (MTL). The thermal degradation behavior and kinetic study of MTL co-pyrolysis with LDPE by microwave-assisted heating was investigated as well. The results indicated that the hydrocarbon content in the bio-oil obtained from microwave co-pyrolysis of MTL and LDPE increased significantly (about 80%). It was also noticed that the aromatic hydrocarbon content increased from 1.94% to 22.83% with the addition of LDPE. Thermal behavior analysis and reaction kinetic study showed that the addition of LDPE into MTL had the effect of promoting thermal degradation and improving reaction rate during microwave-assisted pyrolysis.


Assuntos
Hidrocarbonetos/química , Lignina/química , Óleos Vegetais/química , Polietileno/química , Polifenóis/química , Temperatura Alta , Cinética , Micro-Ondas , Pirólise
8.
Appl Ergon ; 81: 102876, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422257

RESUMO

Back pain is a very common health problem and affects people across the world. This study applies an Inclusive Design approach to a community-based back pain service to understand the challenges, in relation to patients' capabilities, that can affect their access to the service. It consisted of three steps: i) online surveys and interviews with physiotherapists and collected patients' personal online care stories to gather insight into their experiences within the back pain care journeys; ii) estimated services' demands made on patients when they access the service and identified the related challenges and iii) proposed recommendations that could address the challenges for patients to access the service. The study suggests an Inclusive Design approach could help identify capability-related challenges such as vision and memory which could affect people's access to back pain treatment. In addition, the application of the approach also uncovered some non-capability-related challenges.

9.
Food Funct ; 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31433414

RESUMO

Schisandra chinensis (Turcz.) Baill (S. chinensis), a functional food, is used as a tonic and sedative agent in traditional Chinese medicine. Modern pharmacological research has proved that S. chinensis could prevent and treat age-related neurodegenerative diseases. The presence of bioactive lignans in S. chinensis is the main reason for its neuroprotective and cognitive enhancement effects. This study aimed to clarify the mechanism of lignans in S. chinensis in ameliorating learning and memory deficits in Alzheimer's disease (AD) animals. The step-down test and Morris water maze (MWM) test were used to verify the effects of lignans in S. chinensis on learning and memory in AD animals. Then, metabolomics approaches based on ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) were used to clarify the mechanism of lignans in S. chinensis in treating AD. Finally, quantitative analysis of AD-related neurotransmitters in the brain was conducted after treatment with lignans in S. chinensis. In the MWM and step-down tests, lignans in S. chinensis showed a clear ability to ameliorate the impaired learning and memory of AD animals. A total of 31 endogenous metabolites were identified after treatment with lignans in S. chinensis, which were associated with lignans ameliorating learning and memory. These biomarkers were mainly associated with polyunsaturated fatty acid metabolism and amino acid and vitamin metabolism. Moreover, lignans in S. chinensis upregulated the levels of γ-aminobutyric acid (GABA), 5-hydroxytryptamine (5-HT), acetylcholine (Ach), norepinephrine (NE) and glycine (Gly) and downregulate the level of aspartic acid (Asp). Lignans in S. chinensis might alleviate the neurotoxic effects of neurological inflammation and oxidative stress, Aß deposition, and tau phosphorylation via the regulation of multiple endogenous metabolic pathways during pathological AD. The research might provide useful support for the further study of pharmacology and new drug development of lignans in S. chinensis.

10.
Respir Physiol Neurobiol ; 270: 103282, 2019 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31430541

RESUMO

Imbalance between inflammatory Th17 cells and immunosuppressive regulatory T cells (Treg) contributes to the progression of chronic obstructive pulmonary disease (COPD). We aims to investigate roles and mechanisms of secreted frizzled-related protein 2 (sFRP2) in airway inflammation and Th17/Treg differentiation in COPD. sFRP2 was significantly upregulated in the serum of patients with COPD and in human bronchial epithelial (HBE) cells that were exposed to cigarette smoke extract (CSE). sFRP2 was negatively correlated with FEV1/FVC. CSE increased IL-6 and TNF-α in HBE cells, which was reversed by sFRP2 silencing. CSE exposure elevated the percentage of Th17 in CD3+ CD8- cells while reduced the percentage of Treg in CD4+CD25+ cells. Knockdown of sFRP2 in peripheral blood mononuclear cells (PBMCs) attenuated Th17 differentiation and induced Treg differentiation. CSE suppressed the expression of ß-catenin and Cyclin D1 in PBMCs while knockdown of sFRP2 markedly reversed the inhibitory effects of CSE. Wnt/ß-catenin inhibition by Dickkopf-1 reversed the inhibitory effect of si-sFRP2 on the production of inflammatory cytokines and imbalance between Th17 and Treg cells caused by CSE. CSE induced sFRP2 potentiated airway inflammation and disturbed Th17/Treg homeostasis by inhibiting ß-catenin.

11.
Thorac Cancer ; 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31407509

RESUMO

BACKGROUND: Following drug resistance in patients with lung cancer treated by EGFR TKIs, a biopsy is required to obtain sufficient cancer tissue for T790M detection in order to select potential beneficiaries suitable for third-generation EGFR TKIs, such as osimertinib. The purpose of this study was to explore the feasibility of using a new in situ analysis technique based on RNA target sequences to detect EGFR T790M in lung cancer. METHODS: A total of 28 formalin-fixed paraffin-embedded (FFPE) samples from 24 lung adenocarcinoma patients archived in Peking Union Medical College Hospital from 2015 to 2016 were collected. The BaseScope T790M detection technique by in situ hybridization on FFPE slides was used to analyze the mutation of EGFR T790M, and then the results were compared with the data acquired by Scorpions ARMS assay, which is the so-called gold standard for EGFR gene mutation testing. The sensitivity and specificity of the BaseScope T790M detection technique were preliminarily evaluated. RESULTS: Of the 28 FFPE specimens, the average proportion of T790M-positive cells was 35.78% ± 17.68% in 18 samples with EGFR T790M, confirmed by Scorpions ARMS assay, Compared with real-time PCR assay, the sensitivity and specificity of BaseScope T790M were all 100% in our cohort. CONCLUSION: BaseScope T790M assay could be completed on only one FFPE slide and the visualized molecular result overplayed with histomorphological information perfectly, so it may be the alternative method for EGFR T790M evaluation. BaseScope assay has potential clinical utility, and it will be necessary to carry out validation with a large number of cases.

12.
Biomacromolecules ; 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31465208

RESUMO

As a major clinical tumor chemotherapeutic burden, multidrug resistance (MDR) is often a result of up-regulation of P-glycoprotein (P-gp), which strongly enhance anti-cancer drug efflux. The excess mitochondrial reactive oxygen species (ROS) not only could inhibit the function of P-gp through insufficient adenosine triphosphate supply, but also could cause apoptosis in MDR cells. Here, we designed a mitochondria targeting nanoparticulate system (GNPs-P-Dox-GA) for overcoming MDR through enhanced ROS generation, where increased cellular uptake as well as mitochondria accumulation were both realized by glycyrrhetinic acid (GA). Firstly, doxorubicin was conjugated with GA (GA-Dox) and then grafted onto N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer backbone via hydrazone bond (P-Dox-GA). The obtained P-Dox-GA was subsequently attached to the surface of gelatin nanoparticles (GNPs). As gelatin is a substrate of tumor extracellular metal matrix protease-2 (MMP2), GNPs-P-Dox-GA nanoparticles could be degraded and release small size P-Dox-GA to facilitate tumor tissue penetration. After P-Dox-GA internalized by tumor cells under GA mediation, Dox-GA detached from HPMA copolymer through hydrolysis of hydrazone bond and then efficiently delivered to mitochondria. Compared to non-GA modified carriers, GNPs-P-Dox-GA exhibited increased cellular uptake nearly for 4-fold and mitochondria distribution for 8.8-fold, and increased ROS production level for nearly 3-fold, significantly decreased efflux rate (55% compared with Dox group) in drug-resistant HepG2/ADR cells, and then led to improved in vitro anti-tumor efficiency in HepG2/ADR cells (IC50 only 19.5% of unmodified ones) as well as exciting in vivo anti-tumor efficiency on HepG2/ADR heterotopic tumor nude mice (1.75-fold higher TGIR than free drug).

13.
Environ Pollut ; 254(Pt B): 113090, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31465900

RESUMO

Sediment records are widely used to infer impact of atmospheric metal deposition in alpine lakes, however, the legacy effect and catchment erosion of historical pollutants could potentially affect metal influx into lakes. Here, we collect data (including six trace metals and three lithogenic elements) from well-dated sediment cores of seven alpine lakes in southeast Tibet, which is adjacent to southwest China. This area has a documented history of preindustrial pollution. Metals such as cadmium (Cd), zinc (Zn) and arsenic (As) are found at relatively low concentrations until a clear increase is observed after 1950s across lakes. This result is consistent with accelerating atmospheric metal deposition due to socio-economic development in the region. We observe no synchronous trend across lakes in the changes of lead (Pb), copper (Cu) and silver (Ag), which show no significant increase after ∼1950 over the last two centuries in most of the study lakes. The historical trends of 206Pb/207Pb ratio reflect an important source of anthropogenic Pb associated with preindustrial mining and smelting in this study region, suggesting a substantial impact of legacy contamination from ancient mines. Furthermore, the temporal variations in these six anthropogenic metals are largely accounted for by terrigenous elements (e.g. aluminum (Al) and titanium (Ti)) in most of the study lakes, and to a lesser degree by sediment grain sizes and organic matter content, suggesting a significant role of catchment erosion in modulating sediment metal signals. In all, this study highlights the legacy effect of historical pollutants may have enhanced the forcing of catchment erosion in modulating the sediment signals of anthropogenic deposition in southeast Tibet.

14.
AAPS PharmSciTech ; 20(7): 278, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31396732

RESUMO

The study mainly aimed to improve the aqueous solubility of Balofloxacin (BLFX) by preparing the inclusion complexes (ICs) of BLFX with cyclodextrins (CDs). In this study, ICs in solid state were obtained by using beta-CD (ß-CD), 2-hydroxypropyl-ß-CD (HP-ß-CD), 2, 6-dimethyl-ß-CD (DM-ß-CD) through a freeze-drying technique. The formation of ICs was confirmed through Fourier-transform infrared spectroscopy, differential scanning calorimetry, powder X-ray diffraction, nuclear magnetic resonance, and scanning electron microscopy. Results demonstrated that the water solubility and dissolution rates of three ICs were distinctly improved than that of parent BLFX. Bacteriostatic experiment manifested that the antibacterial effect of BLFX was not inhibited after encapsulation in CDs. The damage of BLFX to kidney and liver cells was reduced. Consequently, successful preparation of the ICs of BLFX with CDs provided possibility for devising new dosage form of BLFX, which held great promise for further applications in clinical fields.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31388934

RESUMO

PURPOSE: Human epidermal growth factor receptor 2 (HER2) status is both an independent prognostic factor and a predictive factor for the efficacy of targeted therapy for breast cancer, so it is critical to accurately detect HER2 protein expression and/or gene amplification. According to the recommendations of the 2013 American Society of Clinical Oncology and College of American Pathologists (ASCO/CAP) guidelines for HER2 breast cancer testing, an additional test should be pursued on a different block from the same tumor as one of the options for patients with immunohistochemistry (IHC) 2+ and a HER2/CEP17 ratio of < 2.0 with an average HER2 signals per tumor cell of ≥ 4.0 and < 6.0 by reflex test using dual-probe fluorescence in situ hybridization (FISH) (double-equivocal HER2). Our aim in this study is to explore the consistency of HER2 status between the two blocks. METHODS: We retrospectively analyzed 5685 primary invasive breast cancers between April 2015 and January 2019 from Peking Union Medical College Hospital. For cases with double-equivocal HER2 revealed in initial blocks, HER2 gene status was evaluated by FISH in a different block from the same tumor. The FISH score was interpreted according to the 2013 ASCO/CAP guidelines for HER2 testing. RESULTS: In our cohort of 5685 specimens, the overall HER2 IHC3+, 2+, 1+ and 0 cases were 20.5%, 31.8%, 28.3%, and 19.5%, respectively. Then, 13.7%, 66.3%, and 20.0% of HER2 amplification, non-amplification, and equivocation rates were found, respectively, in IHC2+ patients (n = 1777) by reflex FISH assay. For specimens with double-equivocal HER2 (n = 333), HER2 status was assessed in another block from the same tumor by FISH and then the frequency of HER2 positive, negative, and equivocation was estimated at 5.7%, 22.5%, and 71.8%, respectively. Because double-equivocal HER2 cases are classified in the HER2 negative category by the 2018 ASCO/CAP HER2 testing guidelines, only 1.3% (19/1511) of HER2 positive patients were determined through additional HER2 testing in another block from the HER2 negative population. CONCLUSIONS: HER2 status in different blocks from the same tumor in primary invasive breast cancer was highly concordant. Our data supported the recommendation of the 2018 ASCO/CAP HER2 testing guidelines in breast cancer to remove the suggestion for additional HER2 testing using another block contained in the previous version.

16.
Food Chem ; 298: 125069, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260991

RESUMO

The effects of ethanol treatment on quality characteristics of cherry tomatoes were investigated over 11 days of storage at room temperature (25 °C). Results showed that sensory quality was improved after ethanol treatment, with redder, softer fruits at the edible stage (11 days) compared with control fruit. In addition, the contents of ascorbic acid, sucrose and fructose were elevated after ethanol treatment as well as the concentration of 6-methyl-5-hepten-2-one. Conversely, decreased levels of methyl salicylate (MeSA), guaiacol, (Z)-3-hexenal and (E)-2-hexenal were observed. Selected consumers showed a preference for ethanol-treated cherry tomato fruits compared with controls. Taken together, 0.1% ethanol application has the potential to improve the quality characteristics of cherry tomatoes stored at room temperature.

17.
Adv Mater ; : e1903277, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31348581

RESUMO

Small interfering RNA (siRNA) holds inherent advantages and great potential for treating refractory diseases. However, lack of suitable siRNA delivery systems that demonstrate excellent circulation stability and effective at-site delivery ability is currently impeding siRNA therapeutic performance. Here, a polymeric siRNA nanomedicine (3I-NM@siRNA) stabilized by triple interactions (electrostatic, hydrogen bond, and hydrophobic) is constructed. Incorporating extra hydrogen and hydrophobic interactions significantly improves the physiological stability compared to an siRNA nanomedicine analog that solely relies on the electrostatic interaction for stability. The developed 3I-NM@siRNA nanomedicine demonstrates effective at-site siRNA release resulting from tumoral reactive oxygen species (ROS)-triggered sequential destabilization. Furthermore, the utility of 3I-NM@siRNA for treating glioblastoma (GBM) by functionalizing 3I-NM@siRNA nanomedicine with angiopep-2 peptide is enhanced. The targeted Ang-3I-NM@siRNA exhibits superb blood-brain barrier penetration and potent tumor accumulation. Moreover, by cotargeting polo-like kinase 1 and vascular endothelial growth factor receptor-2, Ang-3I-NM@siRNA shows effective suppression of tumor growth and significantly improved survival time of nude mice bearing orthotopic GBM brain tumors. New siRNA nanomedicines featuring triple-interaction stabilization together with inbuilt self-destruct delivery ability provide a robust and potent platform for targeted GBM siRNA therapy, which may have utility for RNA interference therapy of other tumors or brain diseases.

18.
Cancer Epidemiol ; 62: 101567, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31326849

RESUMO

OBJECTIVES: This study investigated appropriate baseline characteristics for screening a Chinese population at high risk of early lung cancer, assisted by low-dose computed tomography (LDCT) with computer-aided detection (CAD). Included is a discussion of the viability of using LDCT in the screening guideline and optimizing the guideline. METHODS: In 2014, 1016 individuals from Sichuan Province were enrolled who satisfied the criteria for high risk according to the 2013 National Comprehensive Cancer Network (NCCN) Guidelines for Non-Small Cell Lung Cancer. From 2014 to 2018, each subject was followed using LDCT with CAD, and pathologically confirmed lung cancers and baseline nodule characteristics (size and density) were recorded. Positive risk was considered a non-calcified solid or part-solid nodule on LDCT with diameter ≥5 mm and ground-glass nodule ≥8 mm, as newly recommended by the China National Lung Cancer Screening Guideline. RESULTS: From 2014-2018, 13 cases of lung cancer were detected; 5 of these were early stage (38.5%). According to the NCCN criteria, 54 women were included and one of these (1.8%) developed lung cancer. The prevalence of lung cancer was 0.7% at baseline. For the entire population (excluding subjects with a tumor mass at baseline, n = 4), the rate of positivity was 20.4% at baseline; applying the Chinese criteria, the false positive rate was 19.5% (197/1012). CONCLUSIONS: Further studies are warranted to establish appropriate eligible criteria and management strategies for Chinese populations.

19.
Int J Mol Sci ; 20(14)2019 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-31337099

RESUMO

The pharmaceutical clay montmorillonite (MMT) is, for the first time, explored as a carbon monoxide-releasing material (CORMat). MMT consists of silicate double layered structure; its exfoliation feature intercalate the CORM-2 [RuCl(µ-Cl)(CO)3]2 inside the layers to suppress the toxicity of organometallic segment. The infrared spectroscopy (IR) confirmed the existence of ruthenium coordinated carbonyl ligand in MMT layers. The energy-dispersive X-ray spectroscopy (EDX) analysis showed that ruthenium element in this material was about 5%. The scanning electron microscopy (SEM) and transmission electron microscope (TEM) images showed that the layer-structure of MMT has been maintained after loading the ruthenium carbonyl segment. Moreover, the layers have been stretched out, which was confirmed by X-ray diffraction (XRD) analysis. Thermogravimetric (TG) curves with huge weight loss around 100-200 °C were attributed to the CO hot-release of ruthenium carbonyl as well as the loss of the adsorbed solvent molecules and the water molecules between the layers. The CO-liberating properties have been assessed through myoglobin assay. The horse myoglobin test showed that the material could be hydrolyzed to slowly release carbon monoxide in physiological environments. The half-life of CO release was much longer than that of CORM-3, and it has an excellent environmental tolerance and slow release effect.

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