Seasonal variation, source contribution, and impact factors of biogenic organic aerosols in PM2.5 in Nanjing, China

Analytical methodologies for oxidized organic compounds in the atmosphere

“…LC-MS methods have given LOD values from extracts between 0.1 and 10 ng mL −1 for organic acids and 0.075–4 ng mL −1 for organosulfate compounds. 2,38 LODs of 1–25 ng mL −1 have been obtained for carbohydrates by LC-MS. 30…”

“…2,30,38,64 Positive mode ESI is applicable for detection of carbohydrates. 30 Compared to other LC works, the IC-ESI-MS configuration employed by Kwiezinski et al 2 required a separate suppressor and post-column addition of iso-propanol to avoid non-volatile salt stacking in the ion source and to increase the sensitivity, as the eluent was an aqueous solution of potassium hydroxide. With CI employing ammonia and isobutane, it has been possible to detect DNPH derivatives of carbonyls, hydroxyl group compounds derived with 4-nitrobenzonyl chloride, and organic acids derived with 2-nitrophenylhydrazine hydrochloride using positive polarity.…”

“…12 The secondary formation contributed to PM 2.5 only 2.8% in the rural area of Nanjing (China), where emissions of primary compounds had greater contribution including sources such as biomass burning (77.4%), fungal spores (12.2%), plant debris (5.5%), and soil resuspension (2.1%). 30 In addition to local sources, long-distance transportation has been assessed to have a significant effect on the prevalence of compounds in the studied areas. 3,30,31…”

“…30 In addition to local sources, long-distance transportation has been assessed to have a significant effect on the prevalence of compounds in the studied areas. 3,30,31…”

“…30 In addition to local sources, long-distance transportation has been assessed to have a signicant effect on the prevalence of compounds in the studied areas. 3,30,31 Here, we present specic oxidation products of the most common biogenic and anthropogenic VOC compounds, as well as other compounds emitted as primary products or less specic products oxidized from various precursors. We are aware that our selected examples provide only a brief overview as there are many publications presenting a more diverse range of different markers.…”