Carbon Isotopic Analysis of Atmospheric Carbonyls Via Cysteamine Derivatization

Isotopic effects of carbonyls were investigated using the simulation reactions of carbonyls with the cysteamine derivatization. Furthermore, variations of carbon isotopic for three dominant carbonyls including formaldehyde, acetaldehyde, and acetone in the roadside air of Nanning were measured using a developed method. It was found that there was a small difference in δ13C values (0.04 to 0.50‰) between the calculated and measured carbonyl derivatives, indicating that no effects on the carbon isotopic fractionation occurred in the simulation reactions of carbonyls with cysteamine. The subsequent ambient air measurements showed that $${\delta }^{13}$$ C values of formaldehyde, acetaldehyde, and acetone were − 36.02 to − 31.18‰, − 35.35 to − 32.01‰, and − 30.45 to − 29.09‰, respectively. Formaldehyde, acetaldehyde and acetone in the air were all enriched in the early afternoon by round 0.5–6‰ in 13C compared to other sampling durations, which caused likely due to the contribution from positive photo-oxidation production of hydrocarbons. Finally, it was revealed that all the measured $${\delta }^{13}$$ C values (− 36.02 to − 29.09‰) were in the range of the forecasted $${\delta }^{13}$$ C values (− 43.00 to − 26.00‰) in terms of 13C mass balance of carbonyls and their hydrocarbon precursors, indirectly confirming such positive productions in the air.