TY - JOUR
T1 - On the Relative Contribution of Iron and Organic Compounds, and Their Interaction in Cellular Oxidative Potential of Ambient PM2.5
AU - Wang, Yixiang
AU - Salana, Sudheer
AU - Yu, Haoran
AU - Puthussery, Joseph V.
AU - Verma, Vishal
N1 - Publisher Copyright:
© 2022 American Chemical Society.
PY - 2022/8/9
Y1 - 2022/8/9
N2 - Previous studies have indicated the roles of both organic compounds and metals in driving the cellular generation of reactive oxygen species (ROS); however, their contribution has not been adequately quantified using mechanistic approaches. We developed a novel fractionation scheme for the stepwise removal of various classes of organic compounds and metals using a combination of solid phase extraction columns. We applied this fractionation scheme to 10 PM2.5samples collected from the midwestern United States. Because both water-soluble organic carbon (WSOC) and Fe have shown good correlations with cellular ROS, we separated them into different fractions and measured their ability to generate ROS in rat alveolar macrophages. Most of the PM2.5cellular ROS was attributed to the metallic fraction. To further explore the reason for the correlation of WSOC with ROS, we investigated the water solubility of Fe by measuring the total Fe in PM2.5samples. The water-soluble fraction of Fe was tightly correlated with WSOC (r ≥ 0.69), indicating WSOC may have an additional role in cellular oxidative potential, probably through complexation of Fe, in enhancing its water solubility and macrophage ROS activity. This work reveals the role of both Fe and organic compounds through different mechanisms in contributing to PM2.5-driven cellular ROS.
AB - Previous studies have indicated the roles of both organic compounds and metals in driving the cellular generation of reactive oxygen species (ROS); however, their contribution has not been adequately quantified using mechanistic approaches. We developed a novel fractionation scheme for the stepwise removal of various classes of organic compounds and metals using a combination of solid phase extraction columns. We applied this fractionation scheme to 10 PM2.5samples collected from the midwestern United States. Because both water-soluble organic carbon (WSOC) and Fe have shown good correlations with cellular ROS, we separated them into different fractions and measured their ability to generate ROS in rat alveolar macrophages. Most of the PM2.5cellular ROS was attributed to the metallic fraction. To further explore the reason for the correlation of WSOC with ROS, we investigated the water solubility of Fe by measuring the total Fe in PM2.5samples. The water-soluble fraction of Fe was tightly correlated with WSOC (r ≥ 0.69), indicating WSOC may have an additional role in cellular oxidative potential, probably through complexation of Fe, in enhancing its water solubility and macrophage ROS activity. This work reveals the role of both Fe and organic compounds through different mechanisms in contributing to PM2.5-driven cellular ROS.
KW - cellular oxidative potential
KW - chemical fractionation
KW - complexation
KW - macrophage ROS
KW - solid phase extraction
KW - water-soluble iron
KW - water-soluble organic compounds
UR - http://www.scopus.com/inward/record.url?scp=85136486798&partnerID=8YFLogxK
U2 - 10.1021/acs.estlett.2c00316
DO - 10.1021/acs.estlett.2c00316
M3 - Article
AN - SCOPUS:85136486798
SN - 2328-8930
VL - 9
SP - 680
EP - 686
JO - Environmental Science and Technology Letters
JF - Environmental Science and Technology Letters
IS - 8
ER -