A Novel High-Throughput Approach to Measure Hydroxyl Radicals Induced by Airborne Particulate Matter

作者：Son Yeongkwon; Mishin Vladimir; Welsh William; Lu Shou En; Laskin Jeffrey D; Kipen Howard; Meng Qingyu^*

来源：International Journal of Environmental Research and Public Health, 2015, 12(11): 13678-13695.

DOI：10.3390/ijerph121113678

• hydroxyl radical
• oxidative potential
• oxidative stress
• particulate matter
• air pollution
• high throughput analysis
• molecular probe
• exposure assessment

Oxidative stress is one of the key mechanisms linking ambient particulate matter (PM) exposure with various adverse health effects. The oxidative potential of PM has been used to characterize the ability of PM induced oxidative stress. Hydroxyl radical (center dot OH) is the most destructive radical produced by PM. However, there is currently no high-throughput approach which can rapidly measure PM-induced center dot OH for a large number of samples with an automated system. This study evaluated four existing molecular probes (disodium terephthalate, 3-p-(aminophenyl)fluorescein, coumarin-3-carboxylic acid, and sodium benzoate) for their applicability to measure center dot OH induced by PM in a high-throughput cell-free system using fluorescence techniques, based on both our experiments and on an assessment of the physicochemical properties of the probes reported in the literature. Disodium terephthalate (TPT) was the most applicable molecular probe to measure center dot OH induced by PM, due to its high solubility, high stability of the corresponding fluorescent product (i.e., 2-hydroxyterephthalic acid), high yield compared with the other molecular probes, and stable fluorescence intensity in a wide range of pH environments. TPT was applied in a high-throughput format to measure PM (NIST 1648a)-induced center dot OH, in phosphate buffered saline. The formed fluorescent product was measured at designated time points up to 2 h. The fluorescent product of TPT had a detection limit of 17.59 nM. The soluble fraction of PM contributed approximately 76.9% of the center dot OH induced by total PM, and the soluble metal ions of PM contributed 57.4% of the overall center dot OH formation. This study provides a promising cost-effective high-throughput method to measure center dot OH induced by PM on a routine basis.

• 出版日期2015-11
• 单位rutgers