NOW Foods supplements - not quality tested?

Correct, nm, not micron. I mistyped.

Also, 1,000nm particles are not really liposomes. They are called multivesicular bodies (MVBs). They lack the structural and functional characteristics necessary for effective compound delivery, primarily due to poor permeability, rapid clearance, and inefficient compound release. MVBs exceeding 1,000 nm cannot traverse the endothelial barriers of the GI tract or blood-brain barrier. The acidic environment of the stomach and the presence of bile salts in the intestine can disrupt phospholipid bilayers, leading to premature active compound release. Smaller liposomes (100–200 nm) are less prone to aggregation and degradation. The mucosal barrier in the GI tract further favors smaller nanoparticles. Mucus pores range from 10 to 200 nm, allowing sub-100 nm liposomes to diffuse through the glycoprotein network, whereas larger particles (>500 nm) are trapped and eliminated via peristalsis. This size-dependent penetration is critical for liposomes to reach intestinal epithelial cells for absorption. Also, cellular internalization of liposomes occurs via endocytosis, a process highly dependent on particle size. Sub-100 nm liposomes are efficiently taken up by clathrin-mediated endocytosis, while larger vesicles (>200 nm) require alternative pathways like macropinocytosis, which is less efficient and energy-intensive. For example, curcumin-loaded liposomes (~263 nm) demonstrated 2.3-fold higher bioavailability than free curcumin due to enhanced cellular uptake. However, vesicles exceeding 1,000 nm face steric hindrance at cell membranes, limiting their absorption. So for practical purposes, real liposomes that would improve bioavailability of poorly soluble supplements need to be around the 100nm range.