Table 2.

Diffusion and detection of example root exudate metabolites through nanoporous membrane.

Metabolite	%C/C0 Fraction diffuseda	LLOD (nM)	LLOD (µM)	LLOD (nM)
		Standard	Culture micro environment	Metabolite sampling layerb
Valine	0.19 ± 0.025	1.3	1.0	1.6
Alanine	0.16 ± 0.015	1.5	1.0	1.6
Isoleucine	0.14 ± 0.023	1.3	1.6	1.5
Phenylalanine	0.12 ± 0.013	11	10	11
Sucrose	0.10 ± 0.0047	27	48	42
Malic acid	0.10 ± 0.0018	1.4 × 102	2.1 × 102	1.8 × 102

^a%C/C₀ Fraction diffused was determined from amount of materials present in the 20 µL of sample microenvironment and 20 µL metabolite sampling layer after 8 h of diffusion through 50 × 50 µm window.

^bThe detection limit of metabolite sampling layer corresponds to that of sample environment.