Oxidation Of AA Research Articles

Synthesis, structure and electrochemical properties of a new γ-octamolybdate-based 3D inorganic-organic hybrid containing scarce Mo-N bond

A new inorganic–organic hybrid based on γ-[Mo8O26]4–, Ni(bbi)2(bbi)0.5[γ-Mo8O26]0.5·H2O (1) (bbi = 1,1′-(1,4-butanediyl)bis(imidazole)), has been synthesized and structurally characterized by X-ray single-crystal diffraction. [Ni2(bbi)2(bbi)]4+ chains are linked into a 3D framework structure by γ-[Mo8O26]4–, in which γ-[Mo8O26]4– adopts μ4-coodination mode to chelate two Ni2+ through terminal oxygen atoms and two coordinate imidazole-N of bbi ligands via five-coordinated Mo atoms. The Hirshfeld surface analyses have been calculated. The electrochemical performances studies showed that the hybrid not only had bi-functional electrocatalytic activities toward the reduction of BrO3−/Fe3+/H2O2 and the oxidation of AA, but also had the amperometric sensor functions of BrO3−.

In-situ electro-organic conversion of lignocellulosic-biomass product-syringaldehyde to a MWCNT surface-confined hydroquinone electrocatalyst for biofuel cell and sensing of ascorbic acid applications

The development of an alternate environmental friendly electrocatalyst suitable to replace the function of the ferrocene, ferricyanide and prussian blue-based redox-mediators is a challenging research interest. Herein, we introduced a novel method for synthesis of a highly redox-active surface-confined Hydroquinone on MWCNT modified glassy carbon electrode surface, GCE/MWCNT@H2Q using the earth-abundant lignocellulose-biomass product, syringaldehyde (Syn) by one-step potential cycling and potentiostatic polarization method in pH 7 phosphate buffer solution that can show an efficient ascorbic acid electrocatalytic signal better than the conventional redox-mediators suitable to use as an anode in biofuel cell and selective electrochemical sensor applications in neutral pH solution. This new electrode showed a well-defined redox peak at Eo′ = −0.15 V(A2/C2) and 0.0 V(A3/C3) vs Ag/AgCl corresponding to the redox-active molecular species of H2Q and its polymerized product, Poly-H2Q. Based on various physicochemical techniques like Raman, IR, TGA, DTA, TEM, GC–MS, H1-NMR and scanning electrochemical microscope imaging using substrate generation/tip-collection mode, it has been revealed that Syn-precursor underwent a demethoxylation and hydration upon the electrochemical preparation condition. It has been proposed that the Poly-H2Q is an active site for the selective electrocatalytic oxidation of AA in a neutral pH solution.

Development of a solar reflector coating on AA6061 alloy by plasma electrolytic oxidation

A spacecraft consists of various components which will function with maximum efficiency only when their operating temperature is maintained within certain specified ranges. Passive thermal control elements play an important role in maintaining the temperature of spacecraft components within the specified ranges by suitable selection of thermo-optical properties of the surfaces namely absorptance and emittance. Plasma electrolytic oxidation of AA 6061 is studied as a method to develop a solar reflector coating for space applications. The coatings are developed by making use of a silicate-based electrolyte. The influence of electrolyte composition, average current density, processing time, positive on-time and pulse frequency on the thermo-optical behaviour of the coating is studied. The thickness of the PEO coating is optimized so as to attain thermo-optical properties similar or better than conventional sulphuric acid anodizing. The optimized coating is subjected to adhesion and humidity tests as well as various space simulation tests such as thermal cycling and thermo-vacuum performance tests to evaluate the suitability of the coating as a thermal control surface for space application. Coatings obtained by PEO process and conventional sulphuric acid anodizing are further characterized using SEM, EDX, XPS, XRD and nanoprofilometry to have a comparative study of their morphology, microstructure and composition.

Ultrasensitive Reduced Graphene Oxide-Poly(Procion)/Gold Nanoparticles Modified Glassy Carbon Electrode for Selective and Simultaneous Determination of Ascorbic Acid, Dopamine, and Uric Acid

A highly ultrasensitive electrochemical sensor based on electrochemically reduced graphene oxide (ERGO), Procion Red MX-5B (PR) and gold nanoparticles (AuNPs) modified glassy carbon electrode (GCE) was developed. Cyclic voltammetry (CV) was employed to electropolymerize GO-PR mixture on GCE followed by deposition of AuNPs to obtain ERGO-poly(PR)/AuNPs/GCE. The physical properties of the nanocomposite were explored through field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FT-IR). The electrochemical performance of the ERGO-poly(PR)/AuNPs/GCE showed remarkable enhancement in the peak current toward oxidation of AA, DA, and UA with peak potentials separation of 0.21 V for AA-DA, and 0.15 V for DA-UA. Differential pulse voltammetry (DPV) was applied to perform individual and simultaneous analysis of the aforementioned analytes at optimized pH. DPV responses of AA, DA, and UA concentration were obtained over the range of 0.4–110, 0.4–170 and 0.4–150 μM with sensitivities of 0.48, 0.40, and 0.63 μA/μM (S/N = 3), respectively. Limit of detections for AA, DA, and UA were 54, 5.6 and 5.8 nM, respectively. Good repeatability, reproducibility as well as long-term stability were obtained. The developed modified electrode was used successfully to monitor AA, DA, and UA in vitamin C tablets, and human urine samples with favorable recoveries.

Symposium review: Macronutrient metabolism in the growing calf

Recent interest in increasing rates of body weight gain in heifer calves before weaning is based on the promise of an increase in milk production during first lactation. This increase is usually realized by increasing milk or milk replacer intake, delaying the onset of rumen development. Simultaneously feeding liquids and solid feeds brings about new challenges. Macronutrient metabolism in growing calves is reviewed, combining literature from heifer and veal calves with the objective to provide insights useful for developing novel feeding strategies. Growing calves are not efficiently retaining digested N when compared with other growing species. Energy and protein appear to be simultaneously limiting growth. With the possible exception of very young calves, low responses to incremental intakes of AA indicate that the limiting AA rarely explains the low efficiency of N utilization. Nonetheless, there are indications that disproportionate oxidation of AA as a result of AA imbalance may occur, notably in splanchnic tissues. Long-chain fatty acids, absorbed from the milk or calf milk replacer (CMR) are preferentially deposited as body fat, but this strongly depends on the need for ATP, fueled by the oxidation of carbohydrates. Hence, fatty acid oxidation typically decreases with an increased feeding level. Insulin sensitivity in calves is quite high at birth, but decreases independent of feeding strategy in early age to very low levels when compared with other species. Even though changes in insulin sensitivity may be provoked by early life nutrition, these effects are small and rather transient. In heavy calves, insulin sensitivity is invariably low. Large effects of dietary treatments on postprandial glucose and insulin responses, as often observed, are unlikely to be caused by differences in insulin sensitivity. Unlike in pigs, de novo fatty acid synthesis is not a significant route of disposal of glucose absorbed from the intestinal tract. Instead, high lactate fluxes in milk-fed calves suggest this may be an important route of disposal. When combining the feeding of milk or CMR with solid feeds, estimation of the contribution of the individual ration components is difficult, and interactions inside the gastrointestinal tract complicate the estimation of their feeding value. There are indications in veal calves that use of nutrients absorbed from a CMR is not dependent on the level of intake of solid feeds.

Ionic self-assembly of bundles of ultralong SC/MB nanobelts with enhanced electrocatalytic activity for detection of ascorbic acid

The formation of bundles of ultralong nanobelts by an anion biological surfactant sodium cholate (SC) and a cationic dye (MB) through ionic self-assembly approach was obtained. The nanobelts possess smooth surfaces, flat end facets and solid internal structure. This one dimensional self-assembly is dominated by the π–π stacking interactions between MB molecules in concert with the hydrogen bonding between SC molecules. The shape and length of the bundles of SC/MB nanobelts could be easily controlled by changing the SC concentration and the aging temperature. Moreover, the electrocatalytic properties of the SC/MB nanobelts modified electrode were also investigated and the results indicated that the bundles of ultralong SC/MB nanobelts exhibited efficient electrocatalytic activity towards l-ascorbic acid (AA) in phosphate buffer solution (pH = 7.0). In addition, the electrostatic interaction between AA and MB also facilitates the electrons transfer on the surface of the GCE and promotes the oxidation of AA. The present work provides an alternative way to design and fabricate the ultralong 1D nanobelt structures with tunable sizes using small organic molecules. This system may also open up a way for the design and development of optical and electronic devices in the potential bio-applications and electrocatalyst for fuel cells.

Partially Reduced Graphene Oxide Modified Tetrahedral Amorphous Carbon Thin-Film Electrodes as a Platform for Nanomolar Detection of Dopamine

In this study we present for the first time tetrahedral amorphous carbon (ta-C)—a partially reduced graphene oxide (PRGO) hybrid electrode nanomaterial platform for electrochemical sensing of dopamine (DA). Graphene oxide was synthesized with the modified Hummer’s method. Before modification of ta-C by drop casting, partial reduction of the GO was carried out to improve electrochemical properties and adhesion to the ta-C thin film. A facile nitric acid treatment that slightly reoxidized the surface and modified the surface chemistry was subsequently performed to further improve the electrochemical properties of the electrodes. The largest relative increase was seen in carboxyl groups. The HNO3 treatment increased the sensitivity toward DA and AA and resulted in a cathodic shift in the oxidation of AA. The fabricated hybrid electrodes were characterized with scanning electron microscopy (SEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray...

Analysis of Electrochemical Reduction Process of Graphene Oxide and its Electrochemical Behavior

AbstractIn this study, the electrochemical reduction process of GO was investigated with structural and electrochemical analysis on a series of step‐reduced ERGOs. Firstly, the disorder of ERGO decreased and its electron conductivity increased significantly at the initial reduction period, from 0 to −0.5 V, together with the desorption of hydroxyl and the formation of carboxyl. Then OCOH was completely reduced to CO at the potential between −1.0 V and −1.4 V. Finally, reduction of CO was observed from −1.6 V to −1.8 V. On the other hand, the step‐reduced ERGO with gradually varying surficial electrochemical properties gave the opportunity for the analysis of a given redox system. The [Fe(CN)6]3−/4− redox reaction was sensitive to the conductivity of modified ERGOs, but insensitive to the oxy‐functional groups. Oppositely, the Q/HQ redox reaction was mainly effected by the quantity of carboxyl. The oxidation of AA was affected by both the conductivity and oxy‐functional groups. Otherwise, electrostatic interaction was exhibited between reactant and ERGOs for all these three reactions.

Casein infusion rate influences feed intake differently depending on metabolizable protein balance in dairy cows: A multilevel meta-analysis

The effects of casein infusion have been investigated extensively in ruminant species. Its effect on responses in dry matter intake (DMI) has been reviewed and indicated no significant effect. The literature reviewed in the current meta-analysis is more extensive and limited to dairy cows fed ad libitum. A total of 51 studies were included in the meta-analysis and data were fitted to a multilevel model adjusting for the correlated nature of some studies. The effect size was the mean difference calculated by subtracting the means for the control from the casein-infused group. Overall, casein infusion [average of 333g of dry matter (DM)/d; range: 91 to 1,092g of DM/d] tended to increase responses in DMI by 0.18kg/d (n=48 studies; 3 outliers). However, an interaction was observed between the casein infusion rate (IR) and the initial metabolizable protein (MP) balance [i.e., supply minus requirements (NRC, 2001)]. When control cows were in negative MP balance (n=27 studies), responses in DMI averaged 0.28kg/d at mean MP balance (−264g/d) and casein IR (336g/d), and a 100g/d increment in the casein IR from its mean increased further responses by 0.14kg/d (MP balance being constant), compared with cows not infused with casein. In contrast, when control cows were in positive MP balance (n=22 studies; 2 outliers), responses in DMI averaged −0.20kg/d at mean casein IR (339g/d), and a 100g/d increment in the casein IR from its mean further decreased responses by 0.33kg/d, compared with cows not infused with casein. Responses in milk true protein yield at mean casein IR were greater (109 vs. 65g/d) for cows in negative vs. positive MP balance, respectively, and the influence of the casein IR on responses was significant only for cows in negative MP balance. A 100g/d increment in the casein IR from its mean increased further responses in milk true protein yield by 25g/d, compared with cows not infused with casein. Responses in blood urea concentration increased in casein studies (+0.59mM) and the influence of the casein IR was greatest for cows in positive MP balance (0.26 vs. 0.11mM per 100g/d increment). Responses in DMI were also correlated negatively with responses in blood urea concentration only for cows in positive MP balance. Together, these results suggest an association between satiety and deamination and oxidation of AA supplied in excess of requirements for cows in positive MP balance. Therefore, casein stimulated appetite in cows fed MP-deficient diets possibly via the supply of orexigenic AA or through a pull effect in response to an increased metabolic demand. Conversely, casein induced satiety in cows fed diets supplying MP in excess of requirements. Not precluding other factors involved in satiety (e.g., insulin, gut peptides), casein could have increased the supply of AA (e.g., Ser, Thr, Tyr), which might depress appetite at the brain level or increase the deamination and the oxidation of AA in oversupply in agreement with the hepatic oxidation theory.

Spectrophotometric Determination of L-Ascorbic Acid Based on Its Oxidation by Potassium Peroxodisulfate in the Presence of Cu(II) as Catalyst

A new, selective and accurate direct spectrophotometric procedure was developed for the determination of L-ascorbic acid (AA) in pharmaceuticals. Background correction was based on the oxidation of AA by potassium peroxodisulfate in the presence of Cu(II) as a catalyst. The molar absorptivity of the proposed procedure was 1.04 × 104 L/(mol cm) at 262 nm. Beer’s law was obeyed in the concentration range of 0.68–16.00 μg/mL for AA. The detection limit was 0.20 μg/mL, and the relative standard deviation was 0.91% (n = 7) for 8.00 μg/mL AA. Other compounds commonly found in pharmaceutical preparations did not interfere with the detection of AA. The proposed procedure was successfully applied to the determination of AA in pharmaceuticals, and the results obtained agreed with those obtained by iodine titration.

Real-time direct electrochemical sensing of ascorbic acid over rat liver tissues using RuO2 nanowires on electrospun TiO2 nanofibers

This paper reports that the high electrocatalytic activity of RuO2 nanowires grown on electrospun TiO2 nanofibers for the oxidation of l-ascorbic acid (AA); and the application of these materials for direct selective sensing of AA in complex samples. Compared to bare glassy carbon (GC) electrode, RuO2 nanowires on TiO2 nanofibers-loaded GC electrode facilitates the oxidation of AA most drastically among the tested species: AA, 4-acetamidophenol (AP), dopamine (DA), uric acid (UA), and glucose. The amperometric response of RuO2 nanowires on TiO2 nanofibers at the applied potential of 0.018V (vs. SCE) exhibits high sensitivity (268.2±3.7μAmM−1cm−2, n=5), low detection limit (<1.8μM), great linearity, reasonable stability, and exclusive selectivity over AP, DA, glucose and UA at their physiological levels. In differential pulse voltammetry, it is verified that the potential resolution of RuO2 nanowires on TiO2 nanofibers is able to differentiate AA, DA, UA, and AP one from the others. In addition, as prepared RuO2 nanowires on TiO2 nanofibers are successfully applied for direct and selective AA measurements in commercial vitamin samples and for the real-time direct analysis of AA generated from living rat liver tissue in vitro.

Modification of carbon paste electrode with Fe(III)-clinoptilolite nano-particles for simultaneous voltammetric determination of acetaminophen and ascorbic acid.

A novel carbon paste electrode (CPE) modified with Fe(III)-exchanged clinoptilolite nano-particles (Fe(III)-NClino/CPE) was constructed and used for simultaneous voltammetric (CV, SqW and chronoamperometry) determination of ascorbic acid and acetaminophen. Raw and modified zeolites were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM). The square wave peak current was linearly increased in the concentration ranges of 1.0 × 10(-9)-1.0 × 10(-2) mol L(-1) for ascorbic acid and 1.0 × 10(-10-)1.0 × 10(-2) mol L(-1) for acetaminophen with detection limits of 1.8 × 10(-9) mol L(-1) and 9.9 × 10(-10) mol L(-1), respectively. The detection limits of 2.4 × 10(-10) mol L(-1) and 2.5 × 10(-11) mol L(-1) were also obtained for AA and AC in chronoamperometric measurements, respectively. The diffusion coefficients of 7.5 × 10(-5) cm(2) s(-1) and 2.4 × 10(-5) cm(2) s(-1) were respectively calculated for the oxidation of AC and AA by chronoamperometry. The proposed electrode exhibited high sensitivity and good stability, and would be valuable for the clinical assay of ascorbic acid and acetaminophen.

1,4-Bis(imidazole)butane ligand and strontium(ii) directed 1-D chains based on basket-type molybdophosphates and transition metal (TM) linkers

Five unclassical heteropoly blues, (H2bib)3[{TMII(H2O)2}{Sr⊂P6Mo2VMo16VIO73}]·nH2O (TM = Fe (1), Co (2), Ni (3), Cu (4), Zn (5)); bib = 1,4-bis(imidazole)butane), have been hydrothermally synthesized and fully characterized. Compounds 1–5 are based on the basket-shaped [Sr⊂P6Mo2VMo16VIO73]8− (abbreviated as {P6Mo18O73}) units, which consist of a vacant Dawson-type “basket body” {P2Mo14} unit and a “handle”-like {P4Mo4} fragment encasing a Sr2+ cation in the central cage. All the compounds exhibit isostructural 1-D zigzag chains linked by a {TM(H2O)2} unit, which are observed for the first time as 1-D basket-like assemblies connected by a TM linker. The optical band gaps of 1–5 show that they are semiconductor materials and potential photocatalysts. Compound 2 as a representative catalyst exhibits a universal highly efficient degradation ability for typical dyes MB, MO, and RhB under UV light and bifunctional electrocatalytic behavior for oxidation of AA and reduction of NO2−.

Assembly of a basket-like {Sr ⊂ P6Mo18O73} cage from 0D dimmer to 2D network and its photo-/electro-catalytic properties.

A series of basket-like heteropoly blues, formulated as (H4bth)[{Cu(H2O)}2{Sr ⊂ P6MoV2MoVI16O73}]·4H2O (1), {H2bih}3[{FeII(H2O)2}{Sr ⊂ P6MoV2MoVI16O73}]·2H2O (2), (H2bih)3[{CoII(H2O)2}{Sr ⊂ P6MoV2MoVI16O73}]·2H2O (3), (H2bih)3[{NiII(H2O)2}{Sr ⊂ P6MoV2MoVI16O73}]·2H2O (4), (H2bih)2(H2bip)[{Zn (H2O)0.5}{Sr ⊂ P6MoV2MoVI16O73}]·5.5H2O (5), (bth = 1,6-bis(triazole)hexane; bih = 1,6-bis(imidazol)hexane; bip = 1,5-bis(imidazol)pentane) have been synthesized hydrothermally and fully characterized. The structural analysis shows that all the compounds contain two electron reduced polyanions [Sr ⊂ P6MoV2MoVI16O73]8− (abbreviated as {P6Mo18O73}), which consists of a tetra vacant γ-Dawson-type{P2Mo14} unit and a “handle”-shaped {P4Mo4} segment encapsulating a Sr2+ cation in the central cavity. Compound 1 is a 6-connected two-dimensional (2D) layer, which represents the first 2D assembly of basket-type polyoxometalates. Compounds 2–4 are isostructural one-dimensional zigzag chains linked by an M(H2O)2 linker (M = iron for 2, cobalt for 3, and nickel for 4). Compound 5 is a dimeric cluster supported by a binuclear {Zn2(H2O)} unit. The optical band gaps of 1–5 reveal their semiconductive natures. The compounds if used as photocatalysts exhibit a universal high efficiency degradation ability for dyes such as methylene blue, Rhodamine B, and Azon phloxine. The lifetime and reaction mechanism of the catalysts were investigated with a series of experiments. The compounds also show good bifunctional electrocatalytic behavior for the oxidation of ascorbic acid (AA) and reduction of nitrite ions.

The influence of ochratoxin A on DNA adduct formation by the carcinogen aristolochic acid in rats.

quinone oxidoreductase (NQO1) activating AA to DNA adducts, their combined treatment did not lead to either higher NQO1 enzyme activity or higher AA-DNA adduct levels in ex vivo incubations. Oxidation of AA I (8-methoxy-6-nitrophenanthro[3,4-d]-1,3-dioxole-5-carboxylic acid) to its detoxification metabolite, 8-hydroxyaristolochic acid, was lower in microsomes from rats treated with AA and OTA, and this was paralleled by lower activities of cytochromes P450 1A1/2 and/or 2C11 in these microsomes. Our results indicate that a decrease in AA detoxification after combined exposure to AA and OTA leads to an increase in AA-DNA adduct formation in liver and kidney of rats.

Fatty acids, inflammation, and asthma

Fatty acids and consequently diet play an essential role in the formation of inflammatory mediators involved in the pathogenesis of asthma. Because intake variations of omega-6 (n-6) and omega-3 (n-3) fatty acids ultimately determine cell membrane incorporation, changes in diet have the potential to modify downstream production of inflammatory mediators derived from these compounds. It has long been hypothesized that decreasing the n-6/n-3 ratio could reduce the production of more proinflammatory mediators while increasing the formation of downstream metabolites that can serve to limit or resolve inflammation. In turn, these changes would result in improved asthma outcomes or would lower the risk for asthma incidence. This review will focus on the role of fatty acid inflammatory and resolving mediators and will summarize the clinical and epidemiologic data on how diet and obesity alter fatty acid profiles that can contribute to asthma.

Mitochondrial ascorbic acid is responsible for enhanced susceptibility of U937 cells to the toxic effects of peroxynitrite

Otherwise nontoxic levels of peroxynitrite promote toxicity in U937 cells pre-exposed to low micromolar concentrations of l-ascorbic acid (AA). This event was associated with the mitochondrial accumulation of the vitamin and with the early formation of secondary reactive oxygen species and DNA single-strand breaks. The same concentrations of peroxynitrite, however, failed to elicit detectable effects in cells pre-exposed to dehydroascorbic acid (DHA), in which mitochondrial accumulation of vitamin C did not occur despite the identical cytosolic levels. Coherently, oxidation of extracellular AA failed to affect the intracellular concentration of the vitamin, but nevertheless prevented its mitochondrial localization as well as the enhanced response to peroxynitrite. Furthermore, in cells postincubated in vitamin C-free medium, time-dependent loss of mitochondrial AA was paralleled by a progressive decline of susceptibility to peroxynitrite, under the same conditions in which cells retained about half of the initial AA. Using different experimental approaches, we finally showed that the enhancing effects of AA are mediated by events associated with peroxynitrite-dependent superoxide/H2 O2 formation in the mitochondrial respiratory chain. Collectively, these results indicate that mitochondria actively take up vitamin C as AA and respond to otherwise inactive concentrations of peroxynitrite with the mitochondrial formation of secondary species responsible for DNA damage and toxicity. DHA preloading, while leading to the accumulation of identical levels of vitamin C, fails to produce these effects because of the poor mitochondrial accumulation of the vitamin.

Deposited gold nanocrystals enhanced porous PTCA–Cys layer for simultaneous detection of ascorbic acid, dopamine and uric acid

This work described a two-step conjugate synthesis of a porous nanostructured materials (PTCA–Cys) composed of 3,4,9,10-perylenetetracarboxylic acid (PTCA) and l-cysteine (Cys) and then the sensor prepared by the deposited gold nanocrystals (DpAu) immobilized in this nanostructure film was developed. The interesting PTCA–Cys layer not only could provide SH-functionalized interface but also easily forms a stable thin film on the electrode surface with the porous nanostructure, thus, it is very beneficial to electrode modification. Furthermore, with the DpAu film onto PTCA–Cys modified electrode, the proposed sensors exhibited the excellent catalytic activity and the high selectivity toward the oxidation of AA, DA and UA. Moreover, scanning electron microscopy, cyclic voltammetry and different pulse voltammetry were employed to characterize the sensors. Under the optimal conditions, the linear response range for simultaneous detection of AA, DA, and UA were 20–700μM, 2–402μM and 0.4–252.4μM, respectively, and the detection limits were 6.40μM, 0.67μM and 0.12μM (S/N=3). More importance, the proposed method offers promise for simple, rapid and cost-effective analysis of small biomolecules.

Fatty acid transport protein 1 mediates macrophage eicosanoid metabolism

The fatty acid transport protein (FATP) is expressed in tissues with active lipid metabolism including macrophages (MPs). FATP1 is a long and very long chain fatty acyl‐CoA synthetase (ACS). Preliminary data in RAW264.7 MPs over‐expressing (OE) FATP1 showed increases in ACS activity along with a blunting of proinflammatory mediators compared to empty vector (EV); while FATP−/− bone marrow derived MPs (BMDMs) displayed blunted ACS activity with elevations in IL‐6, TNFα and MCP‐1 compared to FATP+/+. We hypothesize that FATP1 modulates availability of fatty acids as fuel or as substrates for eicosanoid synthesis. We aim to investigate if FATP1 modulates eicosanoid metabolism and inflammation in MPs. MPs were treated with 5ng/mL LPS and 10 ng/ml IFNγ to polarize to the pro‐inflammatory M1 subtype, or left untreated. Liquid chromatography mass spectrometry results showed FATP1‐OE drove statistically significant increases in PGD2, PGF2α, 8isoPGF2α and TXB2, and decreases in proinflammatory 11, 12, 15‐HETEs, vs. EV. FATP1‐OE also had lower levels of AA compared to EV through metabolomics. Complementary to OE, FATP1−/− displayed elevated 8, 11, 12, and 15‐HETEs. Future directions will examine FATP‐1 mediated oxidation of AA and incorporation into lipids in macrophages. In conclusion, FATP‐1 decreases MPs inflammation potentially through regulation of eicosanoid production. AA017376Grant Funding Source: R00 AA017376

Poly-xanthurenic acid modified electrodes: An amperometric sensor for the simultaneous determination of ascorbic and uric acids

The poly-xanthurenic acid (poly-Xa)/multi-walled carbon nanotube (MWCNT)/glassy carbon modified electrode (poly-Xa/MWCNT/GCE) was successfully applied for the simultaneous determination of ascorbic (AA) and uric (UA) acids. Cyclic voltammetric results show that the modified electrode displays an excellent eletrocatalytic activity toward the oxidation of AA at a low potential (0.05V versus Ag/AgCl) and anodic peak resolution (ΔEpa), close to 300mV versus Ag/AgCl, in solutions containing AA and UA. Values in the order of 106Lmol−1s−1 were obtained for the kinetic constant kcat for the catalytic oxidation of AA, upon evaluation by cyclic voltammetry, chronoamperometry and RDE. Furthermore, the sensor provided limits of detection of 0.19μmolL−1 and 0.31μmolL−1 for AA and UA, respectively. The sensor was applied for the simultaneous determination of AA and UA in urine samples and the average recoveries for these samples were 99.9 (±2.5)% and 99.9 (±2.6)%, respectively.