Numerous studies have suggested the association of reactive oxygen species (ROS) with adverse health effects derived from exposure to airborne particulate matter (PM) and diesel exhaust particles (DEP). This redox activity has been attributed to both inorganic and organic species present in these particles, but a clear distinction has not been established between the contribution of each. This article describes an application of an analytical procedure, based on the reaction of salicylic acid with hydroxyl radical to form dihydroxybenzoate (DHBA) isomers, to measure transition metal-based redox activity associated with ambient and diesel exhaust particles. In the procedure, ascorbic acid (AA) is used as electron source for reduction of metal ions and oxygen to generate superoxide, which is further reduced to hydroxyl radical in the presence of transition metal ions. Hydroxyl radical reacts with salicylate to generate DHBA isomers, which are measured by high-performance liquid chromatography (HPLC) with electrochemical detector. Both copper (Cu) and iron (Fe) ions generated DHBA isomers in a concentration-dependent manner but at different rates. The procedure was applied to DEP and ambient particles and the results showed Cu ion to be the major contributor to DHBA formation. The procedure provides a quantitative measure of transition metal-based redox activity associated with ambient samples with different physicochemical properties.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1080/08958370802491433 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Correlation Analyses of Amylase and Protease Activities and Physicochemical Properties of Wheat Bran During Solid-State Fermentation.
Foods
December 2024
State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science and Technology, Tianjin 300457, China.
Solid-state fermentation (SSF) has emerged as an effective method for wheat bran valorization, providing advantages like cost reduction, decreased water usage, and enhanced product quality. In this study, wheat bran was fermented using to evaluate the extraction yield of soluble dietary fiber, the activities of protease and amylase, and the physicochemical characteristics of wheat bran during SSF. The findings demonstrated that the maximum yield of soluble dietary fiber was achieved after 120 h of fermentation at a moisture content of 55%.
View Article and Find Full Text PDFPreparation, structural changes and functional properties of the covalent complexes of almond protein and phloretin.
Int J Biol Macromol
January 2025
College of Food Science and Pharmacy, Xinjiang Agricultural University, Urumqi 830052, PR China. Electronic address:
Proteins and polyphenols exhibit distinct biological activities and functional properties. A comprehensive investigation into the formation mechanisms, structures, and functional properties of protein-polyphenol complexes will deepen our understanding of their interactions and establish a theoretical foundation and technical support for development of novel functional foods and pharmaceutical products. The almond protein-phloretin (AP-PHL) covalent complex was synthesized through the covalent binding of hydroxyl radicals to phloretin (PHL), utilizing almond protein (AP) as the raw material.
View Article and Find Full Text PDFBimetallic nanoreactor mediates cascade amplification of oxidative stress for complementary chemodynamic-immunotherapy of tumor.
Biomaterials
December 2024
Key Laboratory of Biomedical Polymers of Ministry of Education & Department of Chemistry, Department of Cardiology, Zhongnan Hospital, Wuhan University, Wuhan, 430072, PR China. Electronic address:
As a promising tumor treatment, chemodynamic therapy (CDT) can specifically catalyze HO into the cytotoxic hydroxyl radical (·OH) via Fenton/Fenton-like reaction. However, the limited HO and weakly acidic pH in tumor microenvironment (TME) would severely restrict the therapeutic efficiency of CDT. Here, a weakly acid activated, HO self-supplied, hyaluronic acid (HA)-functionalized Ce/Cu bimetallic nanoreactor (CBPNs@HA) is elaborately designed for complementary chemodynamic-immunotherapy.
View Article and Find Full Text PDFCarbon quantum dots modification reduces TiO nanoparticle toxicity in an aquatic food chain.
J Hazard Mater
January 2025
Environment Research Institute, Shandong University, Qingdao 266237, China. Electronic address:
Carbon quantum dots (CQDs) are emerging as a promising zero-dimensional carbon nanomaterial with the potential to enhance the catalytic properties of titanium dioxide nanoparticles (TiO NPs). Although CQDs modification alters the physicochemical properties of TiO NPs, the impact on their toxicity has been rarely explored. In this study, we investigated the effects of CQDs doping on the toxicity, bioaccumulation, and trophic transfer of TiO NPs using a representative aquatic food chain comprising phytoplankton (Scenedesmus obliquus), zooplankton (Daphnia magna), and fish (Danio rerio).
View Article and Find Full Text PDFExpression Analysis of Cyst Specific Protein (CSP21) and Cellulose Synthase II (CSII) Genes in Acanthamoeba castellanii Trophozoites Exposed to Silver Nanoparticles Conjugated with Elaeagnus umbellata.
Acta Parasitol
January 2025
Department of Molecular Biology and Genetics, Ordu University, Ordu, Turkey.
Article Synopsis
- Acanthamoeba species are protozoa that can cause serious eye and CNS infections, and current treatments are often ineffective, especially in specific areas like the eye.
- The study evaluates the effectiveness of ethanolic fruit extract of E. umbellata, silver nanoparticles derived from it, and lauric acid in killing Acanthamoeba trophozoites and protecting DNA from damage.
- Results show that these treatments can significantly kill trophozoites and prevent DNA damage, suggesting potential new options for treating Acanthamoeba infections.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!