Zinc phthalocyanine sensitizers that contain phosphinic acid anchoring groups have an overall conversion efficiency of 3.24 % under 1 sun in a dye-sensitized solar cell (DSSC). M. K. Nazeeruddin, T. Torres, M. Grätzel, and co-workers demonstrate in their Communication (DOI: 10.1002/anie.201105950) that the phosphinic acid groups provide a stronger binding ...

A new strategy is established for detecting chiral amino acids based on the electron transfer from hemoglobin Fe(ii) to Cu(ii) in copper complexes of the amino acids. The sensor shows a highly selective recognition of arginine enantiomers.

Albumin transports both fatty acids and zinc in plasma. Competitive binding studied by isothermal titration calorimetry revealed that physiologically relevant levels of fatty acids modulate the Zn-binding capacity of albumin, with far-reaching implications for biological zinc speciation. The molecular mechanism for this effect is likely due to a large conformational ...

The effect of pH, nature of acid and temperature on trace element migration from ceramic ware treated with 18 commercially available glazes was studied. Besides of the well-studied lead and cadmium, migration of other toxic and non toxic elements such as aluminum, boron, barium, cobalt, chrome, copper, iron, lithium, magnesium, ...

Two acidic hot springs close to the crater of Copahue Volcano (Neuquén, Argentina) are the source of the Río Agrio. The river runs several kilometres before flowing into Caviahue Lake. Along the river, temperature, iron, other metal and proton concentrations decrease gradually with distance downstream. From the source to the ...

Fe bioavailability can be manipulated by the nutritional composition of a meal. Ascorbic acid and unidentified components of meat, fish and poultry, but particularly beef, all appear to enhance the absorption of non-haem Fe. The aim of the present study is to identify whether extracts of green-lipped mussels (GLM; Perna ...

Organic complexing agents, such as ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA) and picolinic acid, have been widely used at nuclear sites and are therefore found as common co-contaminants in radioactive contaminated land. This study has explored the mechanisms by which these three complexing agents affect the sorption of Th(IV) to ...

We designed and synthesised carboxymethylmonobenzocyclooctyne (COMBO) through a four-step reaction pathway. COMBO is a new, structurally simple, non-fluorinated, and directly conjugable copper-free click reagent, which shows excellent reaction kinetics, as also evidenced by theoretical calculations. Additionally, the carboxylic acid appendage allows further conjugation to biomolecules or fluorescent labels. The utility ...

AX10185, the phenyl amide of xanthurenic acid, was found to be a sub-100nM inhibitor of Lp-PLA(2). However, in the presence of EDTA the inhibitory activity of AX10185 was extinguished while the enzymatic activity of Lp-PLA(2) did not change. Subsequent metal screening experiments determined the inhibition to be Zn(2+) dependent. Structure-activity ...

Several unexpected reports of iron-sulphur clusters in nucleic acid binding proteins have recently appeared in the literature. Once thought to be relatively rare in these systems, iron-sulphur clusters are now known to be essential components of diverse nucleic acid processing machinery including glycosylases, primases, helicases, nucleases, transcription factors, RNA polymerases ...

A new chemically modified carbon paste electrodes based on Fe (III) schiff base (Fe (III)-SBMCP)-containing graphite pastes were prepared and evaluated as electrochemical sensor for the voltammetric determination of mefenamic acid and indomethacin in aqueous solutions. The measurements were carried out by application of the differential pulse voltammetry (DPV) method ...

Iron(III) ingested as a food component or supplement for iron deficiencies can react with salivary SCN- to produce Fe(SCN)2+ and can be reduced to iron(II) by ascorbic acid in the stomach. Iron(II) generated in the stomach can react with salivary nitrite and SCN- to produce nitric oxide (NO) and FeSCN+, ...

This study was carried out with the aim of identifying the effects of consuming sour-tasting food and refreshing drinks on the bone tissue of teeth among teenagers. The cumulative effect of a year-long exposure of teeth to the erosive effects of a model system of acidic media (citric acid, lactic ...

An unexpected recognition of β-cyclodextrin (CD) from α- and γ-CDs was achieved. The emission from a diboronic acid-containing tetraphenylethene (TPEDB) was amplified upon addition of β-CD, whereas there was almost no response for α-, and γ-CDs. TPEDB is proposed to be anchored onto the wide rim of β-CD through the ...

Copper/silica nanocomposite catalysts prove efficient for the direct hydrocyclization of biomass-derived levulinic acid to cyclic 2-methyltetrahydrofuran in the vapor phase, at moderate hydrogen pressures. A nickel-promoted copper/silica catalyst with a high copper loading (72 wt %) is particularly effective for the direct hydrocyclization (89 % selectivity). The catalysts are stable during long-term experiments, ...

Background/Objectives:Little is known about the long-term effects of maternal multi-micronutrient supplementation on the growth of children during early childhood. In this follow-up study, the effects of maternal supplementation with multi-micronutrients in pregnancy on postnatal child growth are examined.Subjects/Methods:A longitudinal follow-up of a subset of newborns (n=1388) whose mothers were randomly ...

The aim of this study was to investigate the effect of a chelated zero valent iron as catalyst on the oxidation of six organic acids that are generally found in olive mill wastewater. The reaction was carried out in a stirred tank reactor under extremely mild conditions, a temperature of ...

ABSTRACT: BACKGROUND: Recently developed iron co-catalyst enhancement of dilute-acid pretreatment of biomass is a promising approach for enhancing sugar release from recalcitrant lignocellulosic biomass. However, very little is known about the underlying mechanisms of this enhancement. Here, our aim was to identify several essential factors that contribute to ferrous ion-enhanced ...

Choline, as a marker of cholinergic activity in brain tissue, is very important in biological and clinical analysis, especially in the clinical detection of the neurodegenerative disorders disease. This work presents an electrochemical approach for the detection of choline based on prussian blue modified iron phosphate nanostructures (PB-FePO(4)). The obtained ...

A new approach for the synthesis of uniform metal-organic framework (MOF) nanocrystals with controlled- sizes and aspect ratios has been developed using simultaneously nonionic triblock copolymer F127 and acetic acid as stabilizing and deprotonating agents, respectively. The alkylene oxide segments of the triblock copolymer can coordinate with metal ions and ...

Nearly all microbes require iron for growth. The low concentration of iron found in the ocean makes iron acquisition a particularly difficult task. In response to these low iron conditions, many bacteria produce low-molecular-weight iron-binding molecules called siderophores to aid in iron uptake. We report herein the isolation and structural ...

The α-keto acid dependent dioxygenases are a major subgroup within the O2-activating mononuclear non-heme iron enzymes. For this class, the resting ferrous, the substrate plus cofactor-bound ferrous, and the Fe(IV)=O sites of the reaction have been well studied. The initial O2-binding and activation steps are experimentally inaccessible and thus are ...

Although Iran is a high-risk country for esophageal squamous cell carcinoma (ESCC), the contribution of overall nutrient intakes to this high incidence rate is not yet clear. The aim of this study was to examine the association between nutrient patterns and risk of ESCC in Iran. Forty-seven patients with ESCC ...

Copper-catalysed oxidative hydroxylation of arylboronic acids was accomplished in water containing an amphiphilic surfactant, providing facile access to phenol derivatives.

The objective of this study was to demonstrate how different factors can simultaneously influence the oxidative stability of an oil-in-water emulsion, and how these factors can be used to enlarge the variation range of oxidation markers, expressed as peroxide value (PV) and TBARS. Initially, a Plackett-Burman design was used to ...

Tyrosinase plays a critical role in the early stages of the melanin synthetic pathway by catalyzing the oxidation of the substrate. Therefore, tyrosinase inhibitors have been intensively studied in both cosmetic and food industries to develop hypopigmentary agents and prevent enzymatic browning in food. Previously, we reported that kojic acid-amino ...

Present work describes the bioleaching potential of metals from low-grade mining ore containing smithsonite, sphaerocobaltite, azurite and talc as main gangue minerals with adapted consortium of Sulfobacillus thermosulfidooxidans strain-RDB and Thermoplasma acidophilum. Bioleaching potential improved markedly by added energy source, acid preleaching and adaptation of microbial consortium with mixed metal ...

Zero-valent iron (ZVI) consists of an elemental iron core surrounded by a shell of corrosion products, especially magnetite. ZVI is used for in situ removal or immobilization of a variety of contaminants but the mechanisms for removal of arsenic remain controversial and the mobility of arsenic after reaction with ZVI ...

Terbium-sensitized luminescence and its applicability towards the detection of Bacillus spores such as anthrax are of significant interest to research in biodefense and medical diagnostics. Accordingly, we have measured the effects of terbium chelation upon the parameters associated with dipicolinate ligation and spore detection. Namely, the dissociation constants, intrinsic brightness, ...

ABSTRACT: BACKGROUND: Staphylococcus aureus synthesizes two siderophores, staphyloferrin A and staphyloferrin B, that promote iron-restricted growth. Previous work on the biosynthesis of staphyloferrin B has focused on the role of the synthetase enzymes, encoded from within the sbnA-I operon, which build the siderophore from the precursor molecules citrate, alpha-ketoglutarate and ...

Questions have been raised about potentially negative effects of antenatal folic acid use in populations with a high prevalence of vitamin B-12 deficiency. Our objective was to examine the association between maternal folate and vitamin B-12 status in pregnancy on offspring insulin resistance and examine whether the effects of maternal ...

During 20 months of proper operation the full scale passive treatment in Mina Esperanza (SW Spain) produced around 100 mg/L of ferric iron in the aeration cascades, removing an average net acidity up to 1500 mg/L as CaCO(3) and not having any significant clogging problem. Complete Al, As, Cd, Cr, Cu, Ti ...

Solvent extraction of iron(III) from actual sulphate waste pickle liquor was investigated using trialkylphosphine oxide diluted with kerosene. The waste pickle liquor was procured from a local company which deals with the manufacturing of pipes and tubes made of iron and steel. Various parameters were studied to optimise a suitable ...

Herein is presented a strategy for the enantioseparation of amino acids enantiomers using β-CD functionalized Fe(3)O(4) nanospheres, in which β-CD provides the ability to chirally discriminate amino acids enantiomers, while the Fe(3)O(4) nanoparticles serve as magnetic separators.

A novel and efficient microwave-assisted decarboxylative three-component coupling of a 2-oxoacetic acid, an amine and an alkyne (OA2-coulpling) has been developed. This new multicomponent coupling constitutes an efficient approach for the synthesis of polysubstituted propargylamines in the presence of a catalytic amount of copper(I) catalyst.

Fruits of the cultivated eggplant species <i>Solanum melongena</i> and its wild relative <i>Solanum incanum</i> have a high content of hydroxycinnamic acid conjugates, which are implicated in the human health benefits of various fruits and vegetables. Monocaffeoylquinic acid esters, in particular 5-<i>O</i>-(-<i>E</i>)-caffeoylquinic acid, are usually predominant in solanaceous fruits and tubers. ...

In this novel acid-base jointly promoted CuAAC, the combination of CuI/DIPEA/HOAc was developed as a highly efficient catalytic system. The functions of DIPEA and HOAc have been assigned, and HOAc was recognized to accelerate the conversions of the C-Cu bond-containing intermediates and buffer the basicity of DIPEA. As a result, ...

The mechanism proposed by Evans to justify the selectivity obtained in Lewis acid catalysed Diels-Alder reactions of cyclopentadiene with acyloxazolidinones has been generalized and used in the rationalization of selectivities obtained in many other systems. However, we recently proposed an alternative mechanism, on the basis of open-chain mono and bicomplexes, ...

The ligand-free trifluoromethylation of arylboronic acids with a [Ph(2)SCF(3)](+)[OTf](-)/Cu(0) system has been carefully investigated. Aryl-, alkenyl- and heteroarylboronic acids with a variety of functional groups were suitable substrates for this reaction. It is suggested that a CuCF(3) species is formed under the reaction conditions.

Anecdotal evidence from forensic practitioners and studies conducted under controlled conditions have indicated that the reaction between 1,2-indanedione and the amino acids present in latent fingermark deposits is highly susceptible to ambient humidity. The addition of catalytic amounts of zinc chloride to the 1,2-indanedione working solution - usually in the ...

It is suggested that targeted screening for hemochromatosis and iron overload may be worthwhile. The aim of this study was to examine uric acid as a potential indicator of the presence of iron overload. We analyzed adults aged 20 and older in the National Health and Nutrition Examination Survey 1999 ...

In the present work the interactions of nucleic acid bases with and adsorption on clays were studied at two pHs (2.00, 7.00) using different techniques. As shown by Mössbauer and EPR spectroscopies and X-ray diffractometry, the most important finding of this work is that nucleic acid bases penetrate into the ...

Cytochrome P450(SPα) (CYP152B1) isolated from Sphingomonas paucimobilis is the first P450 to be classified as a H(2)O(2)-dependent P450. P450(SPα) hydroxylates fatty acids with high α-regioselectivity. Herein we report the crystal structure of P450(SPα) with palmitic acid as a substrate at a resolution of 1.65 Å. The structure revealed that the ...

Impaired fatty acid synthesis was noted in iron deficient animal models. Human data, however, are scarce. Although Canadian Inuit have a traditional diet rich in heme iron and long chain n-3 fatty acids, recent literature has also indicated the presence of prevalent iron deficiency. We aimed to explore whether the ...

The interaction of iron (hydr)oxides with fatty acids is related to many industrial and natural processes. To resolve current controversies about the adsorption configurations of fatty acids and the conditions of the maximum hydrophobicity of the minerals, we perform a detailed study of the adsorption of sodium laurate (dodecanoate) on ...

Ascorbic acid has been previously discussed to have antitumor potential through its interaction with transition metal ions such as iron and copper. Furthermore, ascorbic acid may act as a reducing agent for Ru(III) compounds such as indazolium trans-[tetrachlorobis(1H-indazole)ruthenate(III)] (KP1019), an investigational anticancer drug which is supposed to be activated by ...

During the steel production in the basic oxygen furnace (BOF), approximately 7-15kg of dust per tonne of produced steel is generated. This dust contains approximately 1.4-3.2% Zn and 54-70% Fe. Regarding the zinc content, the BOF dust is considered to be highly problematic, and therefore new technological processes for recycling ...

The Bacillus subtilis acyl lipid desaturase (Δ5-Des) is an iron-dependent integral membrane protein able to selectively introduce double bonds into long-chain fatty acids. In the last decade since its discovery, the molecular mechanism of Δ5-Des expression has been studied extensively. However, the mechanism of desaturation, which must rely on unknown ...

A 2- year- old boy presented with non responsive megaloblastic anemia, growth failure and developmental delay. Blood levels of B(12), folic acid and iron were normal. Tandem mass spectroscopy for common inborn errors of metabolism did not reveal any abnormality. There was an increased excretion of orotic acid in urine. ...

The reduction effect of various carboxylic acids on inkjet-printed copper film was investigated. Carboxylic acids were exposed to the film by nitrogen gas that was bubbled through the liquid acids during the annealing process. It was observed that in the case of saturated mono-carboxylic acid (formic, acetic, propionic, butyric), the ...