Chitosan-albumin based core shell-corona nano-antimicrobials to eradicate resistant gastric pathogen

In this study, protein/polysaccharide core-shell-corona (PP-CSC) nano delivery systems (NDS) were prepared by using bovine serum albumin (BSA) and chitosan (CS). The potential of PP-CSC-NDS for increasing the stability and bio-accessibility of ε-poly-l-lysine (ε-PL) as effective therapy for gastric Helicobacter pylori was investigated. The presence of CS-shell increased the size (223 ± 1.7 nm) of BSA-core as compared to BSA-shell on CS-core (191 ± 2.6 nm). Conversely, encapsulation efficiency of ε-PL was reduced for C(B)NDS [CS-shell on BSA-core] to 73 ± 1% than 82 ± 2% for B(C)NDS [BSA-shell on CS-core] due to cationic nature of ε-PL. Scanning electron microscopy of PP-CSC-NDS displayed smooth and non-flocculated morphology. FTIR analyses verified that the electrostatic interactions, H-bonding, and hydrophobic effects were involved in PP-CSC formation. Zeta analyses revealed that the net charge depends on the corona layer and the encapsulated antimicrobials. Moreover, CS corona improved the antimicrobial potential, controlled release, mucoadhesion and stability of ε-PL loaded C(B)NDS in simulated gastric fluid due to inherent antimicrobial and mucoadhesive properties of CS polymer. In contrast, protein corona improved the penetration into bacterial biofilms for better eradiation of H. pylori. Thus, conjugated nano-systems with selected corona can improve the overall efficacy of antimicrobials to develop effective nano-therapeutics against gastric infections.