Fig 2.

Physicochemical characterization of DEPs. A, Cryo-electron microscopy (cryo-EM) image of DEPs (1 μg/mL, Krebs-Henseleit solution). B, Size distribution of DEPs (1 μg/mL, Krebs-Henseleit solution), as measured by longest dimension, including agglomerates, derived from cryo-EM images (particle count, 394). Note that agglomerates larger than 600 nm were also present, although in low numbers (see Fig E2). C, TGA weight-loss profile of DEPs when heated to 850°C in air, showing the organic component fraction (a) and inorganic carbon fraction (b). D, Example trace and summary data of the effects of org-DEPs (1 μg/mL), par-DEPs (1 μg/mL), and DEPs (1 μg/mL) in isolated guinea pig (n = 4) and human (n = 2) vagal tissue. Data are expressed as means ± SEMs for guinea pig. Depolarization of human vagal tissue was assessed in response to org-DEPs (0.03 and 0.05 mV) to par-DEPs (0 and 0 mV) and DEPs (0.06 and 0.04 mV).