1
|
Li A, Qiu X, Jiang X, Shi X, Liu J, Cheng Z, Chai Q, Zhu T. Alteration of the health effects of bioaerosols by chemical modification in the atmosphere: A review. FUNDAMENTAL RESEARCH 2024; 4:463-470. [PMID: 38933216 PMCID: PMC11197536 DOI: 10.1016/j.fmre.2023.10.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 06/12/2023] [Accepted: 10/13/2023] [Indexed: 06/28/2024] Open
Abstract
Bioaerosols are a subset of important airborne particulates that present a substantial human health hazard due to their allergenicity and infectivity. Chemical reactions in atmospheric processes can significantly influence the health hazard presented by bioaerosols; however, few studies have summarized such alterations to bioaerosols and the mechanisms involved. In this paper, we systematically review the chemical modifications of bioaerosols and the impact on their health effects, mainly focusing on the exacerbation of allergic diseases such as asthma, rhinitis, and bronchitis. Oxidation, nitration, and oligomerization induced by hydroxyl radicals, ozone, and nitrogen dioxide are the major chemical modifications affecting bioaerosols, all of which can aggravate allergenicity mainly through immunoglobulin E pathways. Such processes can even interact with climate change including the greenhouse effect, suggesting the importance of bioaerosols in the future implementation of carbon neutralization strategies. In summary, the chemical modification of bioaerosols and the subsequent impact on health hazards indicate that the combined management of both chemical and biological components is required to mitigate the health hazards of particulate air pollution.
Collapse
Affiliation(s)
- Ailin Li
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Xinghua Qiu
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Xing Jiang
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Xiaodi Shi
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Jinming Liu
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Zhen Cheng
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Qianqian Chai
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Tong Zhu
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| |
Collapse
|
2
|
Zhang D, Wang J, Chen H, Gong C, Xing D, Liu Z, Gladich I, Francisco JS, Zhang X. Fast Hydroxyl Radical Generation at the Air-Water Interface of Aerosols Mediated by Water-Soluble PM 2.5 under Ultraviolet A Radiation. J Am Chem Soc 2023; 145:6462-6470. [PMID: 36913682 DOI: 10.1021/jacs.3c00300] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
Abstract
Due to the adverse health effects and the role in the formation of secondary organic aerosols, hydroxyl radical (OH) generation by atmospheric fine particulate matter (PM) has been of particular research interest in both bulk solutions and the gas phase. However, OH generation by PM at the air-water interface of atmospheric water droplets, a unique environment where reactions can be accelerated by orders of magnitude, has long been overlooked. Using the field-induced droplet ionization mass spectrometry methodology that selectively samples molecules at the air-water interface, here, we show significant oxidation of amphiphilic lipids and isoprene mediated by water-soluble PM2.5 at the air-water interface under ultraviolet A irradiation, with the OH generation rate estimated to be 1.5 × 1016 molecule·s-1·m-2. Atomistic molecular dynamics simulations support the counter-intuitive affinity for the air-water interface of isoprene. We opine that it is the carboxylic chelators of the surface-active molecules in PM that enrich photocatalytic metals such as iron at the air-water interface and greatly enhance the OH generation therein. This work provides a potential new heterogeneous OH generation channel in the atmosphere.
Collapse
Affiliation(s)
- Dongmei Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Jie Wang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Huan Chen
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Chu Gong
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Dong Xing
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Ziao Liu
- Department of Earth and Environmental Science and Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6316, United States
| | - Ivan Gladich
- Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, P.O. Box 34410, Doha, Qatar
| | - Joseph S Francisco
- Department of Earth and Environmental Science and Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6316, United States
| | - Xinxing Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
- Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300192, China
| |
Collapse
|
3
|
Zhang D, Gong C, Wang J, Mu C, Wang W, Zhang X. Beyond lipid peroxidation: Distinct mechanisms observed for POPC and POPG oxidation initiated by UV-enhanced Fenton reactions at the air-water interface. JOURNAL OF MASS SPECTROMETRY : JMS 2021; 56:e4626. [PMID: 32776645 DOI: 10.1002/jms.4626] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 07/01/2020] [Accepted: 07/13/2020] [Indexed: 06/11/2023]
Abstract
Fenton or Fenton-like reactions are ubiquitous in nature, and the hydroxyl radicals (·OH) generated in these reactions are accountable for a plethora of oxidation processes both in the environment and in vivo. Among these oxidation reactions, lipid oxidation initiated by ·OH radicals has long been oversimplified as a peroxidation mechanism, but in reality, it is a highly complicated process that can result in a large variety of products. Using the unique field-induced droplet ionization mass spectrometry (FIDI-MS) methodology that is capable of selective sampling of amphiphilic molecules that reside at the air-water interface, here, we show distinct mechanisms from the ultraviolet (UV)-enhanced Fenton oxidations of two phospholipids, POPC and POPG, even though these two lipids possess the same functional groups that are vulnerable to ·OH attack. We postulate that it is the different packing densities that determine the permeability of ambient NO molecules into the monolayers, resulting in highly distinct reaction pathways and products. We anticipate that this work will be a wake-up call that the lipid peroxidation mechanism is sometimes taken for granted and that lipid oxidation can be subtly affected by various factors that deserves deeper investigations.
Collapse
Affiliation(s)
- Dongmei Zhang
- Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, China
| | - Chu Gong
- Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, China
| | - Jie Wang
- Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, China
| | - Chaonan Mu
- Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, China
| | - Wei Wang
- Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, China
| | - Xinxing Zhang
- Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), College of Chemistry, Nankai University, 94 Weijin Road, Tianjin, 300071, China
| |
Collapse
|
4
|
Wang J, Zhang X. Free-Radical-Initiated Phospholipid Oxidations at the Air-Water Interface: The Oxidation of Unsaturated and Saturated Fatty Acid Chains. J Phys Chem A 2021; 125:973-979. [PMID: 33470825 DOI: 10.1021/acs.jpca.0c10170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Lipid oxidations initiated by free radicals are usually considered to undergo peroxidation, a chain process starting with hydrogen abstraction by an initiator, followed by O2 uptake. While this peroxidation mechanism is widely accepted and sometimes taken for granted, here we provide evidence of the oxidation of both of the unsaturated and saturated fatty acid chains in phospholipids initiated by photoinitiator 2,4,6-trimethylbenzoyl diphenylphosphine oxide (TMDPO) at the air-water interface, and no peroxidation products are observed in these reactions. A unique field-induced droplet ionization mass spectrometry (FIDI-MS) methodology which is capable of the selective online sampling of monolayers of molecules that reside at the air-water interface is employed to detect the products. We have shown that the double bonds on the oleyl chains of the lipids are first oxidized into epoxides, after which other saturated carbon atoms are oxidized into carbonyl groups. We anticipate that this work will draw more attention to the complexity of the lipid oxidation chemistry initiated by free radicals.
Collapse
Affiliation(s)
- Jie Wang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Nankai University, Tianjin 300071, China
| | - Xinxing Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Center (ReCAST), Nankai University, Tianjin 300071, China
| |
Collapse
|
5
|
Cholesterol provides nonsacrificial protection of membrane lipids from chemical damage at air-water interface. Proc Natl Acad Sci U S A 2018; 115:3255-3260. [PMID: 29507237 DOI: 10.1073/pnas.1722323115] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The role of cholesterol in bilayer and monolayer lipid membranes has been of great interest. On the biophysical front, cholesterol significantly increases the order of the lipid packing, lowers the membrane permeability, and maintains membrane fluidity by forming liquid-ordered-phase lipid rafts. However, direct observation of any influence on membrane chemistry related to these cholesterol-induced physical properties has been absent. Here we report that the addition of 30 mol % cholesterol to 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (POPG) monolayers at the air-water interface greatly reduces the oxidation and ester linkage cleavage chemistries initiated by potent chemicals such as OH radicals and HCl vapor, respectively. These results shed light on the indispensable chemoprotective function of cholesterol in lipid membranes. Another significant finding is that OH oxidation of unsaturated lipids generates Criegee intermediate, which is an important radical involved in many atmospheric processes.
Collapse
|
6
|
Wells JR, Schoemaecker C, Carslaw N, Waring MS, Ham JE, Nelissen I, Wolkoff P. Reactive indoor air chemistry and health-A workshop summary. Int J Hyg Environ Health 2017; 220:1222-1229. [PMID: 28964679 PMCID: PMC6388628 DOI: 10.1016/j.ijheh.2017.09.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 09/18/2017] [Accepted: 09/22/2017] [Indexed: 12/23/2022]
Abstract
The chemical composition of indoor air changes due to the reactive nature of the indoor environment. Historically, only the stable parent compounds were investigated due to their ease of measurement by conventional methods. Today, however, scientists can better characterize oxidation products (gas and particulate-phase) formed by indoor chemistry. An understanding of occupant exposure can be developed through the investigation of indoor oxidants, the use of derivatization techniques, atmospheric pressure detection, the development of real-time technologies, and improved complex modeling techniques. Moreover, the connection between exposure and health effects is now receiving more attention from the research community. Nevertheless, a need still exists for improved understanding of the possible link between indoor air chemistry and observed acute or chronic health effects and long-term effects such as work-related asthma.
Collapse
Affiliation(s)
- J R Wells
- NIOSH/HELD/EAB, Morgantown, WV, USA.
| | | | - N Carslaw
- Environment Department, University of York, York, UK
| | - M S Waring
- Drexel University, Philadelphia, PA, USA
| | - J E Ham
- NIOSH/HELD/EAB, Morgantown, WV, USA
| | - I Nelissen
- Flemish Institute for Technological Research (VITO), Mol, Belgium
| | - P Wolkoff
- National Research Center for the Working Environment, Copenhagen, Denmark
| |
Collapse
|
7
|
Adams EM, Casper CB, Allen HC. Effect of cation enrichment on dipalmitoylphosphatidylcholine (DPPC) monolayers at the air-water interface. J Colloid Interface Sci 2016; 478:353-64. [DOI: 10.1016/j.jcis.2016.06.016] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 06/02/2016] [Accepted: 06/03/2016] [Indexed: 01/07/2023]
|
8
|
Marín-Yaseli MR, González-Toril E, Mompeán C, Ruiz-Bermejo M. The Role of Aqueous Aerosols in the “Glyoxylate Scenario”: An Experimental Approach. Chemistry 2016; 22:12785-99. [DOI: 10.1002/chem.201602195] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Margarita R. Marín-Yaseli
- Departamento de Evolución Molecular; Centro de Astrobiología (INTA-CSIC); Ctra. Torrejón-Ajlavir km 4,8 28850 Torrejón de Ardoz Madrid Spain
| | - Elena González-Toril
- Departamento de Evolución Molecular; Centro de Astrobiología (INTA-CSIC); Ctra. Torrejón-Ajlavir km 4,8 28850 Torrejón de Ardoz Madrid Spain
| | - Cristina Mompeán
- Departamento de Evolución Molecular; Centro de Astrobiología (INTA-CSIC); Ctra. Torrejón-Ajlavir km 4,8 28850 Torrejón de Ardoz Madrid Spain
| | - Marta Ruiz-Bermejo
- Departamento de Evolución Molecular; Centro de Astrobiología (INTA-CSIC); Ctra. Torrejón-Ajlavir km 4,8 28850 Torrejón de Ardoz Madrid Spain
| |
Collapse
|
9
|
Estillore AD, Trueblood JV, Grassian VH. Atmospheric chemistry of bioaerosols: heterogeneous and multiphase reactions with atmospheric oxidants and other trace gases. Chem Sci 2016; 7:6604-6616. [PMID: 28567251 PMCID: PMC5450524 DOI: 10.1039/c6sc02353c] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 07/17/2016] [Indexed: 12/20/2022] Open
Abstract
Once airborne, biologically-derived aerosol particles are prone to reaction with various atmospheric oxidants such as OH, NO3, and O3.
Advances in analytical techniques and instrumentation have now established methods for detecting, quantifying, and identifying the chemical and microbial constituents of particulate matter in the atmosphere. For example, recent cryo-TEM studies of sea spray have identified whole bacteria and viruses ejected from ocean seawater into air. A focal point of this perspective is directed towards the reactivity of aerosol particles of biological origin with oxidants (OH, NO3, and O3) present in the atmosphere. Complementary information on the reactivity of aerosol particles is obtained from field investigations and laboratory studies. Laboratory studies of different types of biologically-derived particles offer important information related to their impacts on the local and global environment. These studies can also unravel a range of different chemistries and reactivity afforded by the complexity and diversity of the chemical make-up of these particles. Laboratory experiments as the ones reviewed herein can elucidate the chemistry of biological aerosols.
Collapse
Affiliation(s)
- Armando D Estillore
- Department of Chemistry & Biochemistry , University of California San Diego , La Jolla , California 92093 , USA . ; ; Tel: +1-858-534-2499
| | - Jonathan V Trueblood
- Department of Chemistry & Biochemistry , University of California San Diego , La Jolla , California 92093 , USA . ; ; Tel: +1-858-534-2499
| | - Vicki H Grassian
- Department of Chemistry & Biochemistry , University of California San Diego , La Jolla , California 92093 , USA . ; ; Tel: +1-858-534-2499.,Scripps Institution of Oceanography and Department of Nanoengineering , University of California San Diego , La Jolla , California 92093 , USA
| |
Collapse
|
10
|
Unexpected products of the hypochlorous acid-induced oxidation of oleic acid: A study using high performance thin-layer chromatographyelectrospray ionization mass spectrometry. J Chromatogr A 2016; 1439:89-96. [DOI: 10.1016/j.chroma.2015.11.059] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 11/08/2015] [Accepted: 11/17/2015] [Indexed: 01/14/2023]
|
11
|
Chapleski RC, Zhang Y, Troya D, Morris JR. Heterogeneous chemistry and reaction dynamics of the atmospheric oxidants, O3, NO3, and OH, on organic surfaces. Chem Soc Rev 2016; 45:3731-46. [DOI: 10.1039/c5cs00375j] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Heterogeneous chemistry of the most important atmospheric oxidants, O3, NO3, and OH, plays a central role in regulating atmospheric gas concentrations, processing aerosols, and aging materials.
Collapse
Affiliation(s)
| | - Yafen Zhang
- Department of Chemistry
- Virginia Tech
- Blacksburg
- USA
| | - Diego Troya
- Department of Chemistry
- Virginia Tech
- Blacksburg
- USA
| | | |
Collapse
|
12
|
Affiliation(s)
- Yuqing Qiu
- Department of Chemistry, The University of Utah, 315
South 1400 East, Salt
Lake City, Utah 84112-0850, United States
| | - Valeria Molinero
- Department of Chemistry, The University of Utah, 315
South 1400 East, Salt
Lake City, Utah 84112-0850, United States
| |
Collapse
|
13
|
Lin W, Clark AJ, Paesani F. Effects of surface pressure on the properties of Langmuir monolayers and interfacial water at the air-water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:2147-2156. [PMID: 25642579 DOI: 10.1021/la504603s] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The effects of surface pressure on the physical properties of Langmuir monolayers of palmitic acid (PA) and dipalmitoylphosphatidic acid (DPPA) at the air/water interface are investigated through molecular dynamics simulations with atomistic force fields. The structure and dynamics of both monolayers and interfacial water are compared across the range of surface pressures at which stable monolayers can form. For PA monolayers at T = 300 K, the untilted condensed phase with a hexagonal lattice structure is found at high surface pressure, while the uniformly tilted condensed phase with a centered rectangular lattice structure is observed at low surface pressure, in agreement with the available experimental data. A state with uniform chain tilt but no periodic spatial ordering is observed for DPPA monolayers on a Na(+)/water subphase at both high and low surface pressures. The hydrophobic acyl chains of both monolayers pack efficiently at all surface pressures, resulting in a very small number of gauche defects. The analysis of the hydrogen-bonding structure/dynamics at the monolayer/water interface indicates that water molecules hydrogen-bonded to the DPPA head groups reorient more slowly than those hydrogen-bonded to the PA head groups, with the orientational dynamics becoming significantly slower at high surface pressure. Possible implications for physicochemical processes taking place on marine aerosols in the atmosphere are discussed.
Collapse
Affiliation(s)
- Wei Lin
- Department of Chemistry and Biochemistry, University of California, San Diego , La Jolla, California 92093, United States
| | | | | |
Collapse
|
14
|
Patterson NH, Thomas A, Chaurand P. Monitoring time-dependent degradation of phospholipids in sectioned tissues by MALDI imaging mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2014; 49:622-7. [PMID: 25044847 DOI: 10.1002/jms.3382] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 04/22/2014] [Accepted: 04/23/2014] [Indexed: 05/24/2023]
Abstract
Imaging mass spectrometry (IMS) is useful for visualizing the localization of phospholipids on biological tissue surfaces creating great opportunities for IMS in lipidomic investigations. With advancements in IMS of lipids, there is a demand for large-scale tissue studies necessitating stable, efficient and well-defined sample handling procedures. Our work within this article shows the effects of different storage conditions on the phospholipid composition of sectioned tissues from mouse organs. We have taken serial sections from mouse brain, kidney and liver thaw mounted unto ITO-coated glass slides and stored them under various conditions later analyzing them at fixed time points. A global decrease in phospholipid signal intensity is shown to occur and to be a function of time and temperature. Contrary to the global decrease, oxidized phospholipid and lysophospholipid species are found to increase within 2 h and 24 h, respectively, when mounted sections are kept at ambient room conditions. Imaging experiments reveal that degradation products increase globally across the tissue. Degradation is shown to be inhibited by cold temperatures, with sample integrity maintained up to a week after storage in -80 °C freezer under N2 atmosphere. Overall, the results demonstrate a timeline of the effects of lipid degradation specific to sectioned tissues and provide several lipid species which can serve as markers of degradation. Importantly, the timeline demonstrates oxidative sample degradation begins appearing within the normal timescale of IMS sample preparation of lipids (i.e. 1-2 h) and that long-term degradation is global. Taken together, these results strengthen the notion that standardized procedures are required for phospholipid IMS of large sample sets, or in studies where many serial sections are prepared together but analyzed over time such as in 3-D IMS reconstruction experiments.
Collapse
|