Polysaccharides, Proteins, and Phytoplankton Fragments: Four Chemically Distinct Types of Marine Primary Organic Aerosol Classified by Single Particle Spectromicroscopy

Table 3

Observed types of marine primary organic aerosol and the suggested biological relevance of specific particle types.

Location	Method(s)	Particle Size	Dominant Component(s) or Spectral Feature	Biological Relevance
Polysaccharides
Arctic𝑎	TEM,	<100 nm	Colloidal spherules	EPS gels
Various𝑏	TEM	<1 𝜇m	Colloidal spherules	EPS gels
	X-ray backscatter,
	and solubility
Mediterranean Sea and	Alcian blue dye	1–50 𝜇m	Semi-transparent colloids	Polysaccharides
Long Island Sound𝑐
W. Pacific𝑑	TEM,	<50 nm	Colloidal spherules	EPS gels
	SEM with X-ray backscatter,
	and solubility
North Atlantic𝑒,∗	HNMR (WSOC and WIOC)	60–1000 nm	Hydroxylate aliphatics	Lipopolysaccharides
			Lipid-like aliphatics
Arctic𝑓	FTIR spectroscopy	<1 𝜇m	Organic hydroxyl groups	Polysaccharides
			Alkane groups
SE Pacific𝑔	FTIR spectroscopy	<1 𝜇m	Organic hydroxyl groups	Polysaccharides
SE Pacificℎ	STXM-NEXAFS	<1 𝜇m	Organic hydroxyl groups	Polysaccharides
Arcticℎ	STXM-NEXAFS	>1 𝜇m	Carboxylic acid groups	Polysaccharides
Protein and amino acid compounds
Arctic𝑖	TEM and Extraction	>50 nm	Hydrophobic organic	Amino acids
			aggregates
Mediterranean Sea and	HPLC and	not provided	Asp, Glu, Ser, Ala	Amino acids
Long Island Sound𝑐	Coomassie Blue dye	1–50 𝜇m	Semi-transparent colloids	Proteins
Arcticℎ	STXM-NEXAFS	>1 𝜇m	Alkane and	Protein
			amide groups
SE Pacificℎ	STXM-NEXAFS	>1 𝜇m	Alkane and	Protein
			amide groups
Micro-organisms and their fragments
Arctic𝑖	TEM and Extraction	400 nm		Bacteria and diatoms
Arctic𝑎	TEM,	200–5000 nm		Micro-organisms and
				fragments
	X-ray backscatter,
	and solubility
W. Pacific𝑑	TEM,	>400 nm	CaCO3	Coral-related
	SEM with X-ray backscatter,	3.7 to 7.5 𝜇m		Bacteria
	and solubility
SE Pacificℎ	STXM-NEXAFS	<1 𝜇m	CaCO3 and alkane groups	Calcareous phytoplankton
				fragments
None listed
Tasmania𝑗	PALMS	>160 nm	Organic mass fragments
Arctic𝑘	TEM	>100 nm	Organic liquid	Proteins
Ireland𝑙	IC,	<1.5 𝜇m	WIOC (not characterized)
	EGA,		WSOC (aliphatic groups
	HNMR,		near heteroatoms, HULIS,
	and TOC		and partially oxidized
			species)

∗HNMR characterized aerosol was generated in a laboratory setting from collected seawater.
𝑎[25], 𝑏[26], 𝑐[22], 𝑑[27], 𝑒[7], 𝑓[8], 𝑔[15], ℎThis work, 𝑖[28], 𝑗[14], 𝑘[42], 𝑙[6].