The effect of pH and temperature on the stability of amphiphilic nanoparticles for therapeutic management of atherosclerosis

Arterial plaques are accumulations of foam cells which are formed due to an unregulated uptake of oxidized low density lipoproteins (oxLDL) via scavenger receptors - mainly CD36 and Scavenger Receptor A1 (SR-A1) - by macrophages. This accumulation of the foam cells leads to plaque development. There are several limitations of conventional pharmaceutics such as failure to address all the symptoms that are caused by atherosclerosis, low efficacy at a given dosage, and side effects². Amphiphilic macromolecules called nanoparticles, comprise of amphilic shell and a hydrophobic core, and are a novel and promising alternative in treating atherosclerosis. In previous studies, a particular combination of shell containing polymers with carboxylic anion (1cM) and mucic acid with lauroyl side chains (M₁₂) core nanoparticles have shown to noticeability down-regulate the expression of scavenger receptors on the surface of human monocyte derived macrophages (HMDMs)¹. However, the intracellular interactions of these nanoparticles are still largely unclear. Investigating the intracellular behavior and stability of the nanoparticles may lead to clues to the bioactive mechanism that results in the down-regulation of SRAs. In this work, the effect of pH and temperature on the nanoparticle´s stability were examined.