Ternary Alloys Encapsulated within Different MOFs via a Self-Sacrificing Template Process: A Potential Platform for the Investigation of Size-Selective Catalytic Performances.

Functional nanoparticles encapsulated within metal-organic frameworks (MOFs) as an emerging class of composite materials attract increasing attention owing to their enhanced or even novel properties caused by the synergistic effect between the two functional materials. However, there is still no ideal composite structure as platform to systematically analyze and evaluate the relation between the enhanced catalytic performance of composites and the structure of MOF shells. In this work, taking RhCoNi ternary alloy nanoflowers, for example, first the RhCoNi@MOF composite catalysts sheathed with different structured MOFs via a facile self-sacrificing template process are successfully fabricated. The structure type of MOF shells is easily adjustable by using different organic molecules as etchant and coordination reagent (e.g., 2,5-dihydroxyterephthalic acid or 2-methylimidazole), which can dissolve out the Co or Ni element in the alloy template in a targeted manner, thereby producing ZIF-67(Co) or MOF-74(Ni) shells accordingly. With the difference between the two MOF shells in the aperture sizes, the as-prepared two RhCoNi@MOF composites preform distinct size selectivity during the alkene hydrogenation. This work would help us to get more comprehensive understanding of the intrinsic role of MOFs behind the enhanced catalytic performance of nanoparticle@MOF composites.

Anti-H1N1 influenza effects and its possible mechanism of Huanglian Xiangru Decoction.

ETHNOPHARMACOLOGICAL RELEVANCE: Huangliang Xiangru Decoction (HXD), which is described in a famous TCM monograph "Book of Nanyang for Life Savin", is frequently used for treating cold in summer and summer heat-dampness. AIM OF THE STUDY: To date, no pharmacological study on the anti-H1N1 influenza properties of HXD has been reported. The aim of the present study was to evaluate the therapeutic action of HXD on HIN1-induced acute pulmonary inflammation and its anti-influenza mechanism focus to TLRs signal pathway in a mouse model. MATERIALS AND METHODS: the mice were intranasally infected with influenza virus to induce viral pneumonia, and then treated with different doses of HXD. The Lung index and pathological changes in the lung tissue of mice were investigated to value the anti-influenza virus effect of HXD. The concentrations of cytokines (IL-2, IL-6, TNF-α and IFN-γ) and anti-oxidant factor (NO, SOD and GSH) in serum of mice were determined with ELISA. RT-PCR and Western blot were used to determine the mRNA and protein expression of TLR3, TLR7, MyD88,TRAF3 and NF-κB p65 in the lung tissues, which are the key targets of TLRs pathway. RESULTS: Compared with the infection group, the lung index of mice in ribavirin group, HXD high dose group and HXD middle dose group were significantly decreased, the lung indexes of these groups were 10.36±1.14mg/g, 9.89±0.79mg/g, and 10.97±0.67mg/g. Moreover, pathological changes were remarkable alleviated. HXD can reduce the contents of IL-6, TNF-α and IFN-γ, NO, and increase the contents of IL-2, SOD, GSH in serum of infected-mice significantly. At the same time, HXD can reduce the mRNA and protein expression of TLR3, TLR7, MyD88,TRAF3 and NF-κB p65 in the lung tissues of infected-mice significantly. CONCLUSIONS: HXD has significant effects on H1N1 influenza by a quantity-effect relationship, and plays its anti-influenza effect by enhancing the body's antioxidant capacity, regulating the body's immune function and the host's TLRs pathway.

Inferoposterior duodenal approach for laparoscopic pancreaticoduodenectomy.

AIM: To investigate the advantages of inferoposterior duodenal approach (IPDA) for laparoscopic pancreaticoduodenectomy (LPD). METHODS: A total of 36 patients subjected to LPD were admitted to the Affiliated Yijishan Hospital of Wannan Medical College from December 2009 to February 2015. These patients were diagnosed with an ampullary tumour or a pancreatic head tumour through computed tomography, magnetic resonance imaging or endoscopic retrograde cholangiopancreatography preoperatively. The cases were selected on the basis of the following criteria: tumour diameter < 4 cm; no signs of peripheral vascular invasion; evident lymph node swelling; and distant metastasis. Of the 36 cases, 20 were subjected to anterior approach (AA; AA group) and 16 were subjected to IPDA (IPDA group). Specimen removal time, intraoperative blood loss and postoperative complications in the two groups were observed, and their differences were compared. RESULTS: During the operation, 2 cases in the AA group and 2 cases in the IPDA group were converted to laparotomy; these cases were excluded from statistical analysis. The remaining 32 cases successfully completed the surgery. The AA group and IPDA group exhibited the specimen removal time of 205 ± 52 and 160 ± 35 min, respectively, and the difference was significant (P < 0.01). The AA group and IPDA group revealed the intraoperative blood loss of 360 ± 210 mL and 310 ± 180 mL, respectively, but these values were not significantly different. Postoperative pathological results revealed 4 cases of inferior common bile duct cancer, 8 cases of duodenal papillary cancer, 6 cases of ampullary cancer, 13 cases of pancreatic cancer, 3 cases of chronic pancreatitis accompanied with cyst formation or duct expansion, and 2 cases of mucinous cystic tumour in the pancreatic head. The postoperative complications were pulmonary Staphylococcus aureus infection, incision faulty union, ascites induced poor drainage accompanied with infection, bile leakage, pancreatic leakage and delayed abdominal bleeding. CONCLUSION: In IPDA, probing for important steps can be performed in early stages, surgical procedures can be optimised and operation time can be shortened.

Comparative pharmacokinetics of rhein and chrysophanol after oral administration of Quyu Qingre granules in normal and acute blood stasis rabbits.

ETHNOPHARMACOLOGICAL RELEVANCE: Quyu Qingre granules (QYQRGs) are useful traditional Chinese composite prescription in the treatment of blood stasis syndrome. Comparing differences of pharmacokinetic properties of compounds in QYQRG between normal and blood stasis syndrome rabbits can provide much helpful information. The primary objective of this study was to compare the pharmacokinetics of rhein and chrysophanol after orally administering 2.0 g/kg b.w. QYQRG in normal and acute blood stasis model rabbits. MATERIALS AND METHODS: The blood samples were collected subsequently at 5, 10, 15, 20, 30, 45, 60, 75, 90, 120, 240, 360 and 480 min after orally administrating QYQRG. The concentrations of rhein and chrysophanol in rabbit plasma were determined by HPLC and main pharmacokinetic parameters were obtained. RESULTS: The pharmacokinetic parameters AUC(0-∞), T(lag), Cmax and K21 of both rhein and chrysophanol were markedly different in the acute blood stasis model rabbits. It was also found that parameters A, ß, MRT and T(1/2ß) of rhein and the parameters α and T1/2α of chrysophanol all exhibited significant difference between the normal and acute blood stasis model rabbits. CONCLUSIONS: The absorption time of rhein and chrysophanol was accelerated and the absorption amount of these two compounds was increased in rabbits with acute blood stasis, suggesting that rhein and chrysophanol would possibly be the two effective compounds in QYQRG.

Silver-gold alloy nanoclusters as a fluorescence-enhanced probe for aluminum ion sensing.

In this paper, the development of a simple method is described for preparing highly red fluorescent mercaptosuccinic acid stabilized AgAu alloy nanoclusters (MSA-AgAu NCs) through the core etching of Ag nanoparticles (NPs) and a galvanic exchange reaction using nonorganic solvent and no multistep centrifuge washing. The as-prepared MSA-AgAu NCs were characterized using spectroscopic and microscopic techniques. After covalently attaching methoxy-poly(ethylene glycol)-NH2 (m-PEG-NH2), PEGylated MSA-AgAu NCs were still stable even in 1 M NaCl. Probably based on the deposition of Al(3+)-enhanced fluorescence, the PEGylated MSA-AgAu NCs offered highly selective and sensitive sensing of Al(3+) in aqueous solution with a detection limit of 0.8 µM.

Graphene and graphene-based nanomaterials: the promising materials for bright future of electroanalytical chemistry.

Similar to its popular older cousins of fullerene and carbon nanotubes (CNTs), the latest form of nanocarbon, graphene, is inspiring intensive research efforts in its own right. As an atomically thin layer of sp(2)-hybridized carbon, graphene possesses spectacular electronic, optical, magnetic, thermal and mechanical properties, which make it an exciting material in a variety of important applications. In this review, we present the current advances in the field of graphene electroanalytical chemistry, including the modern methods of graphene production, and graphene functionalization. Electrochemical (bio) sensing developments using graphene and graphene-based materials are summarized in more detail, and we also speculate on their future and discuss potential progress for their applications in electroanalytical chemistry.

A novel electrochemiluminescence sensor based on bis(2,2'-bipyridine)-5-amino-1,10-phenanthroline ruthenium(II) covalently combined with graphite oxide.

This communication reports a novel electrochemiluminescence (ECL) sensor based on covalently linking bis(2,2'-bipyridine)-5-amino-1,10-phenanthroline ruthenium(II) (Ru(II)-NH2) with graphite oxide (GO) on a glassy carbon electrode. 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride and N-hydroxy-succinimide were applied to activate the carboxyl groups on the GO surface and catalyze the formation of amido link between Ru(II)-NH2 and carboxyl groups on GO. The composite film was characterized using atomic force microscopy, transmission electron microscopy and Fourier transform infrared absorption spectroscopy. Based on ECL experimental results, the composite film modified electrode displayed high electrochemical activity towards the oxidation of 2-(dibutylamino) ethanol (DBAE). Under optimized conditions, the linear response of ECL intensity to DBAE concentration was valid in the range 6.0×10(-7)-2.0×10(-4) mol L(-1) (r2=0.9948) with a detection limit (S/N=3) of 5.0×10(-8) mol L(-1). Furthermore, the ECL sensor presented good characteristics in terms of stability and reproducibility, promising the development of ECL sensors for biologically important compounds.

A facile synthesis of palladium nanoparticles supported on functional carbon nanotubes and its novel catalysis for ethanol electrooxidation.

In this study, a novel material, palladium nanoparticles-carboxylic functional carbon nanotubes (PdNPs-CFCNTs), based on PdNPs supported on CFCNTs was synthesized by a facile spontaneous redox method. The material reveals high electrochemical activity and excellent catalytic characteristic for alcohol electrooxidation on a glassy carbon electrode (GCE) in an alkaline medium. The preparation mechanism was studied by the galvanic cell effect between PdCl(4)(2-) and functional defect sites on CFCNTs. Results from UV-visible absorption spectroscopy and electrochemical impedance spectroscopy revealed that the reduction of PdCl(4)(2-) to metallic Pd was successfully achieved. Morphologies of PdNPs supporting on CFCNTs (PdNPs-CFCNTs) were also characterized by transmission electron micrograph. PdNPs-CFCNTs with the best electrocatalytic characteristics were obtained under the condition as: the weight ratio of Pd to CFCNTs was kept at 2:1, the temperature was kept at 70 degrees C in the synthesis, and the scan rate of the applied potential was selected at 60 mV s(-1). The results indicate that PdNPs-CFCNTs could be a great potential material in direct ethanol fuel cells and ethanol sensors.

A novel non-enzymatic ECL sensor for glucose using palladium nanoparticles supported on functional carbon nanotubes.

A novel non-enzymatic electrochemiluminescence (ECL) sensor based on palladium nanoparticles (PdNPs)-functional carbon nanotubes (FCNTs) was discovered for glucose detection. PdNPs were homogeneously modified on FCNTs using a facile spontaneous redox reaction method. Their morphologies were characterized by transmission electron microscopy (TEM). Based on ECL experimental results, the PdNPs-FCNTs-Nafion film modified electrode displayed high electrocatalytic activity towards the oxidation of glucose. The free radicals generated by the glucose oxidation reacted with the luminol anion (LH(-)), and enhanced the ECL signal. Under the optimized conditions, the linear response of ECL intensity to glucose concentration was valid in the range from 0.5 to 40 micromol L(-1) (r(2)=0.9974) with a detection limit (S/N=3) of 0.09 micromol L(-1). In addition, the modified electrode presented high resistance towards the poisoning of chloride ion, high selectivity and long-term stability. In order to verify the sensor reliability, it was applied to the determination of glucose in glucose injection samples. The results indicated that the proposed approach provided a highly sensitive, more facile method with good reproducibility for glucose determination, promising the development of a non-enzymatic ECL glucose sensor.

[Effect of oxygen on the fluorescence of sol-gel with ruthenium complexes].

Different Ru complexes were used in an organically modified sol-gel (ormosil) sensing film to character their quenching behaviors to oxygen. The sensing film with tris-(4,7-diphenyl-1, 10-phenanthroline) ruthenium(II) [Ru(dpp)(2+)3] as an indicator was selected because of its characteristics with high quenching efficiency, fast response time, high luminescence intensity and long-term stability. The quenching behavior of the sensing film greatly depended on the content of dimethyldimethoxysilane (DiMe-DMOS) in ormosil because DiMe-DMOS changed the polarity of sensing film. A home-made fluorescence quenching system was set up for oxygen determination based on a blue LED (lambda max = 460 nm ) as an exciting light source. Th e response time was 30 s from saturatednitrogen to oxygen in water, and 90 s from saturated oxygen to nitrogen.

[Oxygen sensing film based on organically modified sol-gel with ruthenium complexes and their fluorescent spectra studies].

A new kind of organically modified sol-gel (ormosil) as a matrix for oxygen-sensitive sensor, in which dimethyldimethoxysilane was selected as an organic modifier in the precursor is described. The fluorescent behaviors of different ruthenium complexes in solution and ormosil film were studied. The sensing film with different kind ruthenium complex as an indicator developed in this paper was characterized in terms of efficiently quenched by oxygen. A new ormosil provides a more desirable environment for oxygen response through increasing film hydrophobicity by the content of the nonbridging Si-CH3 groups has been discussed. The sensing film with tris-(4,7-diphenyl-1,10-phenanthroline) ruthenium(II) as an indicator is selected because of its characteristic with high quenching efficiency, fast response time, high luminescence intensity and long-term stability.