One-pot synthesis of alginate-antimicrobial peptide nanogel

SALVATI, BRIANNE; FLÓREZ-CASTILLO, JOHANNA MARCELA; SANTAGAPITA, PATRICIO ROMÁN; BARJA, BEATRIZ C.; PERULLINI, MERCEDES

Photochemical and Photobiological Sciences

ROYAL SOC CHEMISTRY

Año: 2024

1474-905X

Nanosized alginate-based particles (NAPs) were obtained in a one-pot solvent-free synthesis procedure, achieving the designof a biocompatible nanocarrier for the encapsulation of IbM6 antimicrobial peptide (IbM6). IbM6 is integrated in the nascentnanosized hydrogel self-assembly guided by electrostatic interactions and by weak interactions, typical of soft matter.The formation of the nanogel is a dynamic and complex process, which presents an interesting temporal evolution. In thiswork, we optimized the synthesis conditions of IbM6-NAPs based on small-angle X-ray scattering (SAXS) measurementsand evaluated its time evolution over several weeks by sensing the IbM6 environment in IbM6-NAPs from photochemicalexperiments. Fluorescence deactivation experiments revealed that the accessibility of different quenchers to the IbM6 peptideembedded in NAPs is dependent on the aging time of the alginate network. Lifetimes measurements indicate that thedeactivation paths of the excited state of the IbM6 in the nanoaggregates are reduced when compared with those exhibitedby the peptide in aqueous solution, and are also dependent on the aging time of the nanosized alginate network. Finally, theentrapment of IbM6 in NAPs hinders the degradation of the peptide by trypsin, increasing its antimicrobial activity againstEscherichia coli K-12 in simulated operation conditions.