@article {He2024,
	title = {Empirical Approach to Quantifying Sensitivity in Different Chemical Ionization Techniques for Organonitrates and Nitroaromatics Constrained by Ion{\textendash}Molecule Reaction and Transmission Efficiency},
	journal = {Analytical Chemistry},
	volume = {96},
	number = {42},
	year = {2024},
	month = {oct},
	pages = {16882{\textendash}16890},
	publisher = {American Chemical Society},
	abstract = {Accurate identification and quantification of nitro-containing species are of great significance to understanding their chemical behaviors in the atmosphere. By optimizing the operational conditions of the H3O+ and NO+ ionization modes in a proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF-MS) and evaluating the performance of an iodide chemical ionization mass spectrometer (I{\textendash} CIMS), this study leveraged the individual advantages of each ionization mode to effectively detect a diverse array of nitroaromatics and organonitrates (ONs). The H3O+ ionization mode largely fulfilled the criteria for real-time monitoring of gas-phase alkyl-, aryl-, and hydroxy-nitrates, and nitrophenols, albeit its reduced sensitivity toward ONs due to extensive fragmentation. In contrast, the NO+ mode demonstrated enhanced sensitivity for ONs with less fragmentation than the H3O+ mode. The I{\textendash} CIMS featured distinguished sensitivity toward oxidized compounds containing polar functional groups, particularly increasing with the incorporation of hydroxyl, carboxyl, or nitrate groups. Further, we developed a calibration-based semiquantitative framework to enhance the accuracy of sensitivity estimation, constrained by ion{\textendash}molecule reaction, transmission efficiency, along with possible decomposition of ion-clusters, with uncertainties ranging from 21\% to 41\% for H3O+ and 21{\textendash}43\% for NO+. Given considerable discrepancies (up to 1 order of magnitude) between measured and predicted sensitivity in I{\textendash} CIMS using previously reported log{\textendash}linear fitting, a declustering voltage (dV50)-based categorization approach was introduced, leading to a 5-fold improvement in measurement accuracy and an overall uncertainty of I{\textendash} CIMS in quantifying nitro-containing species varying from 27\% to 60\%.},
	issn = {0003-2700},
	doi = {10.1021/acs.analchem.4c03751},
	url = {https://doi.org/10.1021/acs.analchem.4c03751},
	author = {He, Shuyu and Ying Liu and Song, Mengdi and Xin Li and Shengrong Lou and Ye, Chenshuo and Liu, YingJun and Yi Liu and Ye, Jiarong and Sihua Lu and Zhou, Wenxin and Xinghua Qiu and Zhu, Tong and Limin Zeng}
}
