Exploring the Potential of Three-Layered Self-assembled Biomaterial-Based Dry Powder Inhaler for Enhanced Structural Integrity and Lung Deposition of Bioactive Lysozyme

Aquasome (AQ) is one of the most recently developed self-assembled novel nanocarrier systems that is predominantly effective due to its property of maintaining the structural integrity of proteins, peptides, and delicate bioactive molecules. The objective of the present study was to investigate the feasibility of AQ as a carrier for dry powder inhalers (DPI) to achieve enhanced aerosol performance for lysozyme (LYS). The water-in-water emulsification method was explored to prepare AQ by using gelatin and cellobiose. The lyophilized LYS-loaded AQ-based dry powder inhaler (DPI) (AQ/LYS-DPI) was evaluated and compared with commercial form of DPI (C-DPI) for its physicochemical properties, in vitro lung deposition, circular dichroism (CD), hemolysis assay, and toxicity study. The developed AQ/LYS-DPI had a particle size of 104.3 ± 3.8 µm, drug loading of 88.70 ± 2.4, and zeta potential of − 8.4 mV with sustained release up to 18 h. The mass median aerodynamic diameter (MMAD) and fine particle fraction (FPF) of AQ/LYS-DPI were found to be 2.43 ± 0.27 µm and 61.52 ± 0.38%, respectively, reflecting enhanced lung deposition. The CD, hemolytic activity, and toxicity study revealed better structural integrity and biocompatibility with no signs of inflammation or toxicity in the formulation. It was observed that the developed AQ/LYS-DPI effectively controls the structural integrity of lysozyme and can be explored as a novel carrier for pulmonary administration of bioactive molecules.