TY - JOUR
T1 - Integration of sub-organ quantitative imaging LA-ICP-MS and fractionation reveals differences in translocation and transformation of CeO2 and Ce3+ in mice
AU - Chen, Beibei
AU - Lum, Judy Tsz Shan
AU - Huang, Yingyan
AU - Hu, Bin
AU - Leung, Kelvin Sze Yin
N1 - Funding Information:
Beibei Chen and Bin Hu gratefully acknowledged the financial support by the National Natural Science Foundation of China (Nos. 21575108, 21575107, 21205090). Kelvin Sze-Yin Leung thanks the funding support from the Inter-institutional Collaborative Research Scheme (RC-ICRS/16-17/02B), Inter-disciplinary Research Matching Scheme (RC-IRMS/16-17/01A) and State Key Laboratory of Environmental and Biological Analysis (SKLP-1617-P03), Hong Kong Baptist University. Kelvin S. –Y. Leung also acknowledges the Science, Technology and Innovation Commission of Shenzhen (JCYJ20170817173243420) for funding support. Yingyan Huang is supported by a postgraduate studentship offered by the University Grants Committee.
Publisher copyright:
© 2019 Elsevier B.V.
PY - 2019/11/15
Y1 - 2019/11/15
N2 - Information on the risk of exposure to cerium oxide (CeO2) nanoparticles (NPs) is limited. To assess risk, we must know where and how such NPs are distributed to the body after exposure, both short- and long-term. In this work, an integrated approach of quantitative LA-ICP-MS bioimaging and fractionation was employed to study the translocation and transformation of CeO2 and Ce3+ in mouse spleen and liver. The complementary information retrieved by the two techniques above on the accumulation of Ce and dissolution/aggregation were found consistent. In brief, a detailed fine scanning of a region of interest in the organ was performed after fast-screening at low spatial resolution. In the spleen, after short-term high-dose exposure, CeO2 NPs was found mainly in the marginal zone and caused an up-regulation of Zn in the white pulp. After long-term low-dose exposure, CeO2 was found in the marginal zone and white pulp. In the liver, CeO2 NPs were mainly distributed in the Kupffer cells and lobule periphery. The high spatial resolution LA maps of H&E-stained liver sections allowed imaging close to cell level; this enabled an estimation of Ce content in Kupffer cells. Furthermore, fractionation by ultrafiltration was also employed to differentiate the ionic and NP species in the organs. This fractionation showed aggregation of Ce ions in spleen, supporting the LA-ICP-MS results. Transmission electron microscopy revealed that long-term CeO2 exposure triggered an immune response to infection in the spleen and confirmed the differential deposition of Ce in the marginal zone. The integrated analyses based on ICP-MS together with histology and TEM investigation suggests that long-term low doses of CeO2 NPs may cause toxicity in the liver and impair functions of the immune system.
AB - Information on the risk of exposure to cerium oxide (CeO2) nanoparticles (NPs) is limited. To assess risk, we must know where and how such NPs are distributed to the body after exposure, both short- and long-term. In this work, an integrated approach of quantitative LA-ICP-MS bioimaging and fractionation was employed to study the translocation and transformation of CeO2 and Ce3+ in mouse spleen and liver. The complementary information retrieved by the two techniques above on the accumulation of Ce and dissolution/aggregation were found consistent. In brief, a detailed fine scanning of a region of interest in the organ was performed after fast-screening at low spatial resolution. In the spleen, after short-term high-dose exposure, CeO2 NPs was found mainly in the marginal zone and caused an up-regulation of Zn in the white pulp. After long-term low-dose exposure, CeO2 was found in the marginal zone and white pulp. In the liver, CeO2 NPs were mainly distributed in the Kupffer cells and lobule periphery. The high spatial resolution LA maps of H&E-stained liver sections allowed imaging close to cell level; this enabled an estimation of Ce content in Kupffer cells. Furthermore, fractionation by ultrafiltration was also employed to differentiate the ionic and NP species in the organs. This fractionation showed aggregation of Ce ions in spleen, supporting the LA-ICP-MS results. Transmission electron microscopy revealed that long-term CeO2 exposure triggered an immune response to infection in the spleen and confirmed the differential deposition of Ce in the marginal zone. The integrated analyses based on ICP-MS together with histology and TEM investigation suggests that long-term low doses of CeO2 NPs may cause toxicity in the liver and impair functions of the immune system.
KW - CeO nanoparticle exposure
KW - LA-ICP-MS
KW - Sub-organ bioimaging
KW - Transformation
KW - Translocation
UR - http://www.scopus.com/inward/record.url?scp=85069826545&partnerID=8YFLogxK
U2 - 10.1016/j.aca.2019.07.044
DO - 10.1016/j.aca.2019.07.044
M3 - Journal article
C2 - 31472707
AN - SCOPUS:85069826545
SN - 0003-2670
VL - 1082
SP - 18
EP - 29
JO - Analytica Chimica Acta
JF - Analytica Chimica Acta
ER -