Pharmacological evaluation of a new nanoformulation in the erectile tissue of rabbits and humans.

The failure of achieving a penile erection for satisfactory sexual intercourse is known as erectile dysfunction (ED). The primary mediator for penile erection is nitric oxide (NO). ED is often associated with endothelial/nitrergic dysfunction characterized by a reduction of the bioavailability of NO.

Evaluating BTEX in vehicle exhaust gas: A fast and efficient approach using SPME and GC-BID.

Benzene, toluene, ethylbenzene, and the xylene isomers (m, p, and o-xylene) (BTEX) are known for their harmful effects on human health and have been extensively studied across various environmental matrices. However, quantifying BTEX in exhaust gases poses challenges due to the complexity of the matrices. In this study, we investigated a method development strategy involving solid-phase microextraction (SPME) and gas chromatography coupled with a dielectric barrier discharge ionization Detector (BID) for quantifying BTEX emitted from internal combustion engines operating at idle.

FeCo@hydrochar nanocomposites as efficient peroxymonosulfate activator for organic pollutant degradation.

Sulfate radical-based advanced oxidation processes (SR-AOPs) are renowned for their exceptional capacity to degrade refractory organic pollutants due to their wide applicability, cost-effectiveness, and swift mineralization and oxidation rates. The primary sources of radicals in AOPs are persulfate (PS) and peroxymonosulfate (PMS) ions, sparking significant interest in their mechanistic and catalytic aspects. To develop a novel nanocatalyst for SR-AOPs, particularly for PMS activation, we synthesized carbon-coated FeCo nanoparticles (NPs) using solvothermal methods based on the polyol approach.

Degradation of xanthene-based dyes by photoactivated persulfate: experimental and computational studies.

Dyes are naked-eye detectable even at low concentration levels and can cause environmental damage when released into aquatic effluents; therefore, methods for removing the residual color from the aquatic media are always a current issue. In this paper, degradation of three xanthene dyes, Rhodamine B, Eosin Y, and Sodium Fluorescein, using photoactivated persulfate was evaluated at pH 3.0 and 11.

Antibacterial and antifungal action of CTAB-containing silica nanoparticles against human pathogens.

New antibiotic agents are urgently needed worldwide to combat the increasing tolerance and resistance of pathogenic fungi and bacteria to current antimicrobials. Here, we looked at the antibacterial and antifungal effects of minor quantities of cetyltrimethylammonium bromide (CTAB), ca. 93.

Nitroprusside─Expanding the Potential Use of an Old Drug Using Nanoparticles.

For more than 70 years, sodium nitroprusside (SNP) has been used to treat severe hypertension in hospital emergency settings. During this time, a few other clinical uses have also emerged such as in the treatment of acute heart failure as well as improving mitral incompetence and in the intra- and perioperative management during heart surgery. This drug functions by releasing nitric oxide (NO), which modulates several biological processes with many potential therapeutic applications.

The biofilm inhibition activity of a NO donor nanosilica with enhanced antibiotics action.

Nitric oxide (NO) has emerged as a promising antibacterial agent, where NO donor compounds have been explored. Here, we investigated the role of a silica nanoparticle containing nitroprusside (MPSi-NP) as a NO donor agent against methicillin-sensitive (ATCC 25,923 and ATCC 12228) and methicillin-resistant (ATCC 700,698 and ATCC 35984) Staphylococcus strains. Biofilm inhibition was studied along with antibiotic activity in combination with standard antibiotics (ampicillin and tetracycline).

Redox cycling of copper mediated by hydrazine: efficient catalyst systems for oxidative degradation of rhodamine B.

Catalytic processes based on Fenton-like reactions on the degradation of organic pollutants have been improved by accelerating the redox cycling of metal ions. This work presents, at first, the results obtained for the heterogeneous degradation of rhodamine B (RhB) by copper ferrite (CuFeO) in presence of hydrogen peroxide (HO) and hydrazine (NH) as redox cycle accelerator. Atomic absorption spectroscopy showed small amounts of Cu are leached from ferrite highlighting the influence of the homogeneous catalysis in the whole process.

Chemometric tools applied to optimize a fast solid-phase microextraction method for analysis of polycyclic aromatic hydrocarbons in produced water.

Chemometric tools are powerful strategies to efficiently optimize many processes. These tools were employed to optimize a fast-solid phase microextraction procedure, which was used for the analysis of polycyclic aromatic hydrocarbons (PAHs) in oil-based produced water using a Headspace-Solid Phase Microextraction technique (HS-SPME/GC-MS). This optimization was achieved with a 2 factorial design approach, where the final conditions for this extraction procedure were 10 μg L, 1 h, 92 °C (at headspace), and 0.

A divergent mode of activation of a nitrosyl iron complex with unusual antiangiogenic activity.

Nitric oxide (NO) and nitroxyl (HNO) have gained broad attention due to their roles in several physiological and pathophysiological processes. Remarkably, these sibling species can exhibit opposing effects including the promotion of angiogenic activity by NO compared to HNO, which blocks neovascularization. While many NO donors have been developed over the years, interest in HNO has led to the recent emergence of new donors.

Incorporation of Nitroprusside on Silica Nanoparticles-A Strategy for Safer Use of This NO Donor in Therapy.

Silica-based nanoparticles have been developed as powerful platforms for drug delivery and might also prevent undesired side effects of drugs. Here, a fast method to synthesize positively charged mesoporous silica nanoparticles (ζ = 20 ± 0.5 mV, surface area = 678 m g, and 2.

Effect of Crotalus basiliscus snake venom on the redox reaction of myoglobin.

In this work, we have studied the effect of Crotalus basiliscus snake venom on the redox reaction of myoglobin (Mb), and by means of electrochemical techniques, we have shown that this reaction is undoubtedly affected following the interaction with the venom. Surface plasmon resonance, electrophoresis, UV-Vis, and circular dichroism showed that the interaction involves the attachment of some constituent of the venom to the protein, although not affecting its first and secondary structures. Mass spectra support this suggestion by showing the appearance of signals assigned to the Mb dimer and to a new species resulting from the interaction between Mb and the venom proteins.

Chitosan Film Containing an Iron Complex: Synthesis and Prospects for Heterocyclic Aromatic Amines (HAAs) Recognition.

Hybrid organic-inorganic materials have been seen as a promising approach to produce sensors for the detection and/or recognition of heterocyclic aromatic amines (HAAs). This work shows the synthesis of a hybrid film as a result of the incorporation of [Fe(CN)(NH)] into chitosan (CS); CS-[(CN)Fe(NH)]. The sensitivity of CS-[(CN)Fe(NH)] toward HAA-like species was evaluated by using pyrazine (pz) as probe molecule in vapor phase by means of electrochemistry and spectroscopic techniques.

Application of the QuEChERS method for the determination of organochlorine pesticide residues in Brazilian fruit pulps by GC-ECD.

The Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was applied to the extraction of 14 organochlorine pesticides (OCPs) residues from commercial fruit pulps available in supermarkets in Fortaleza, Northeastern Brazil. The analyses were carried out by gas chromatography (GC), coupled to an electron-capture detector (ECD), and were confirmed by GC-tandem mass spectrometry (MS). The parameters of the analytical method, such as accuracy, precision, linear range, limits of detection and quantification, were determined for each pesticide.

Brazilian fruit pulps as functional foods and additives: evaluation of bioactive compounds.

Eight tropical fruit pulps from Brazil were simultaneously characterised in terms of their antioxidant and antimicrobial properties. Antioxidant activity was screened by DPPH radical scavenging activity (126-3987 mg TE/100g DW) and ferric reduction activity power (368-20819 mg AAE/100g DW), and complemented with total phenolic content (329-12466 mg GAE/100g DW) and total flavonoid content measurements (46-672 mg EE /100g DW), whereas antimicrobial activity was tested against the most frequently found food pathogens. Acerola and açaí presented the highest values for the antioxidant-related measurements.

Mixed-valence state of symmetric diruthenium complexes: synthesis, characterization, and electron transfer investigation.

Complexes of the type {[(pyS)Ru(NH(3))(4)](2)-μ-L}(n), where pyS = 4-mercaptopyridine, L = 4,4'-dithiodipyridine (pySSpy), pyrazine (pz) and 1,4-dicyanobenzene (DCB), and n = +4 and +5 for fully reduced and mixed-valence complexes, respectively, were synthesized and characterized. Electrochemical data showed that there is electron communication between the metal centers with comproportionation constants of 33.2, 1.

Isoniazid metal complex reactivity and insights for a novel anti-tuberculosis drug design.

For over a decade, tuberculosis (TB) has been the leading cause of death among infectious diseases. Since the 1950s, isoniazid has been used as a front-line drug in the treatment of TB; however, resistant TB strains have limited its use. The major route of isoniazid resistance relies on KatG enzyme disruption, which does not promote an electron transfer reaction.

Reaction of bis(2,4-dinitrophenyl) phosphate with hydrazine and hydrogen peroxide. Comparison of O- and N- phosphorylation.

Nonionic hydrazine reacts with anionic bis(2,4-dinitrophenyl) phosphate (BDNPP), giving 2,4-dinitrophenyl hydrazine and dianionic 2,4-dinitrophenyl phosphate by an S(N)2(Ar) reaction, and at the phosphoryl center, giving 2,4-dinitrophenoxide ion and a transient phosphorylated hydrazine that rearranges intramolecularly to N-(2,4-dinitrophenyl)-N-phosphonohydrazine. Approximately 58% of the reaction at pD = 10 occurs by N-phosphorylation, as shown by (31)P NMR spectroscopy. Reaction of HO(2)(-) is wholly at phosphorus, and the intermediate peroxophosphate reacts intramolecularly, displacing a second 2,4-dinitrophenoxide ion, or with H(2)O(2), giving 2,4-dinitrophenyl phosphate and O(2).

Mechanisms of nucleophilic substitution reactions of methylated hydroxylamines with bis(2,4-dinitrophenyl)phosphate. Mass spectrometric identification of key intermediates.

Mono- and dimethylation of hydroxylamine on nitrogen does not significantly affect rates of initial attack of NHMeOH and NMe(2)OH on bis(2,4-dinitrophenyl)phosphate (BDNPP), which is largely by oxygen phosphorylation. O-Methylation, however, blocks this reaction and NH(2)OMe then slowly reacts with BDNPP via N-attack at phosphorus and at the aryl group. With NHMeOH, the initial product of O-attack at phosphorus reacts further, either by reaction with a second NHMeOH or by a spontaneous shift of NHMe to the aryl group via a transient cyclic intermediate.

Reactions of bis(2,4-dinitrophenyl) phosphate with hydroxylamine.

For dephosphorylation of bis(2,4-dinitrophenyl) phosphate (BDNPP) by hydroxylamine in water, pH region 4-12, the observed first-order rate constant, k(obs), initially increases as a function of pH, but is pH-independent between pH 7.2 and pH 10. The initial BDNPP cleavage by nonionic NH(2)OH (<0.