Diffusion-mediated carving of interior topologies of all-natural protein nanoparticles to tailor sustained drug release for effective breast cancer therapy

Protein nanoparticles as drug delivery systems for cancer theranostics

Protein-based nanoparticles have garnered significant attention in theranostic applications due to their superior biocompatibility, exceptional biodegradability and ease of functionality. Compared to other nanocarriers, protein-based nanoparticles offer additional advantages, including biofunctionality and precise molecular recognition abilities, which make them highly effective in navigating complex biological environments. Moreover, proteins can serve as powerful tools with self-assembling structures and reagents that enhance cell penetration. And their derivation from abundant renewable sources and ability to degrade into harmless amino acids further enhance their suitability for biomedical applications. However, protein-based nanoparticles have so far not realized their full potential. In this review, we summarize recent advances in the use of protein nanoparticles in tumor diagnosis and treatment and outline typical methods for preparing protein nanoparticles. The review of protein nanoparticles may provide useful new insights into the development of biomaterial fabrication.

Salting-out effect-mediated size-control of protein nanoparticles towards controllable microstructures for sustained release of eugenol

Size and monodispersity of solid particles are essential to their structuring behaviors at biphasic interfaces. However, delicate control over biomolecular nanoparticle sizes is challenging. In this study, we prepared monodisperse rice protein (RP) nanoparticles by neutralizing RP solutions (pH 12.0) using combined treatments of cationic exchange resins (CERs) and HCl. CERs absorbed Na+ by releasing H+ without producing salt during neutralization. By compromising the usages of CERs and HCl when preparing RPs, the generation of NaCl can be delicately tailored, leading to controllable nanoparticle sizes from 20 nm to 30 nm. By mixing these nanoparticles with eugenol in an aqueous solution, the nanoparticles accommodated eugenol in their cores due to inward diffusion. Furthermore, such eugenol-contained nanoparticles with different sizes demonstrated tunable releases of eugenol due to size-dependent capillary forces, which can be harnessed for suppression of microbial growth on fruit with prolonged effective eugenol concentration.

Engineering Self-Assembled Nanomedicines Composed of Clinically Approved Medicines for Enhanced Tumor Nanotherapy

The traditional nanocarriers are typically constructed to deliver anticancer agents for improving drug bioavailability and enhancing chemotherapeutic efficacy, but this strategy suffers from the critical issue of nanocarrier biosafety that hinders further clinical translation. In this work, a unique nanomedicine (PTX@ICG) has been rationally constructed by combining two clinically approved agents, i.e., paclitaxel (PTX) and indocyanine green (ICG), by a facile ultrasound-assisted self-assembly methodology. The formation of the nanostructure can effectively increase the enrichment of PTX and ICG molecules in the tumor site, and improve the utilization factor of hydrophobic PTX. Moreover, since the molecule interaction in PTX@ICG is mainly Van der Waals forces, the self-assembled structure can be spontaneously dissociated under laser irradiation and release PTX in situ to achieve safe tumor-targeted chemotherapy. Simultaneously, the released ICG can act as photothermic agents for photothermal therapy (PTT), thus combining chemotherapy and PTT to obtain an enhanced tumor nanotherapy via facile self-assembly. The synergistic chemo/photothermal tumor nanotherapy achieved the efficient tumor cell-killing effect and tumor-ablation ability, as systematically demonstrated both in vitro and in vivo. This work provides a distinct paradigm of the self-assembled nanomedicine design for effectively improving the drug bioavailability to achieve high antitumor efficacy.