Nitrogen-Drag-Assisted Crosslinking by Glucose to Obtain Bovine Serum Albumin–SGI-1027 Nanoparticles

Background/Objectives: Nanoparticle (NP) technology is a promising tool against atherosclerosis, an inflammatory disease of large- and medium-sized arteries and an underlying cause of cardiovascular disease. Notably, DNA methyltransferase inhibitors such as SGI-1027 are anti-inflammatory. SGI-1027 tissue target specificity and potency may improve when loaded into an NP. We have previously shown that SGI-1027 nanoencapsulation with serum albumin NPs is anti-inflammatory in cell culture and anti-atherogenic in vivo. Nonetheless, nanoencapsulation relied on glutaraldehyde, which limits pharmacological applications. To increase NP biocompatibility, we assessed an alternative crosslinking method based on glucose and solvent drag to synthesize bovine serum albumin (BSA) NP loaded with SGI-1027. We assessed the physicochemical and functional parameters of BSA NPs loaded with increasing SGI-1027 doses (0, 0.05, and 0.1 mg). Results: We found that SGI-1027 encapsulation improves key NP properties in a SGI-1027-dose-dependent fashion: NP yield, drug encapsulation efficiency, morphology, and morphometrics; on the other hand, the ζ-potential and polydispersity were not affected. A molecular interaction between BSA and SGI-1027 was found at 1057–906 cm−1 using FT-IR. Raman spectroscopy revealed a fingerprint of SGI-1027 encapsulated into BSA at 728–650 cm−1, corresponding to the 2,4-diamino-6-methylpyrimidine of SGI-1027. NPs were internalized by mouse peritoneal macrophages, where accumulation at the cell membrane border, cytoplasm, and nuclear membrane was observed only when loaded with SGI-1027. Internalization coincided with an anti-inflammatory response. Conclusions: We found a synergistic effect between glucose and N2 (solvent drag) on protein self-assembly nanostructuration; this methodology offers an alternative to glutaraldehyde and heat crosslinking to encapsulate hydrophobic or thermolabile drugs.