Factors influencing the fabrication of albumin-bound drug nanoparticles (ABDns): part I. Albumin-bound betulinic acid nanoparticles (ABBns).

Though there are many albumin-based drug delivery systems (ABDDS) in the market, it is not known whether ABDDS can be applied across all chemical classes. In this study, we applied ABDDS to a poorly water-soluble drug betulinic acid (BA) to improve its aqueous solubility. Monomeric albumin-bound BA (ABBns) nanoparticles can be fabricated in the range of 10-20 nm. BA self-assembled with HSA at 0.1:1 to 2:1 molar ratio within 0.5 h in phosphate buffer pH 7.4 and 8.4. Approximately, 85-90% BA could be loaded onto HSA in the presence of Tween 20 (T20) and sodium cholate (NaC). The release of BA from ABBns was linear over 5 days. In conclusion, for poorly water-soluble acidic drugs, a suitable solubiliser can release the drug from HSA binding site, depending on the aggregation number and affinity of the solubiliser for the HSA binding site.

Factors influencing the fabrication of albumin-bound drug nanoparticles (ABDns): Part II. Albumin-bound carbamazepine nanoparticles (ABCns).

Carbamazepine (CBZ) is a BCS Class II drug with poor solubility profile. In order to improve the physicochemical properties of CBZ, albumin (HSA)-bound CBZ nanoparticles (ABCns) were prepared. Drug-loading studies indicated that monomeric ABCns can be fabricated by self-assembly of anhydrous form III of CBZ and HSA in molar ratios of 1:1 or 2:1 within 0.5 h in phosphate buffer pH 7.4 with particle size in the range of 10-20 nm. Approximately 73-76% of the CBZ was encapsulated within HSA and 20-40% CBZ was released from the ABCns over 8 days. In conclusion, novel ABCns can be fabricated with sustained-release of CBZ for over 8 days which can significantly improve the physicochemical profile of CBZ.