Hyperthermia/glutathione-triggered ferritin nanoparticles amplify the ferroptosis for synergistic tumor therapy

Breast cancer is the most diagnosed malignancy in women globally, and drug resistance is among the major obstacles to effective breast cancer treatment. Emerging evidence indicates that photothermal therapy and ferroptosis are both promising therapeutic techniques for the treatment of drug-resistant breast tumors. In this study, we proposed a thermal/ferroptosis/magnetic resonance imaging (MRI) triple functional nanoparticle (I@P-ss-FRT) in which ferritin, an iron storage material with excellent cellular uptake capacity, was attached via disulfide bonds onto polydopamine coated iron oxide nanoparticle (I@P) as photothermal transduction agent and MRI probe. I@P-ss-FRT converted the near-infrared light (NIR) into localized heat which accelerated the release of ferrous ions from ferritin accomplished by glutathione reduction and subsequently induced ferroptosis. The drug-resistant cancer cell lines exhibited a more significant uptake of I@P-ss-FRT and sensitivity to PTT/ferroptosis compared with normal cancer cell lines. In vivo, I@P-ss-FRT plus NIR displayed the best tumor-killing potential with inhibitory rate of 83.46 %, along with a decline in GSH/GPX-4 content and an increase in lipid peroxides generation at tumor sites. Therefore, I@P-ss-FRT can be applied to combat drug-resistant breast cancer.

Synthesis and Advanced Characterization of Polymer–Protein Core–Shell Nanoparticles

Enzyme immobilization techniques are widely researched due to their wide range of applications. Polymer–protein core–shell nanoparticles (CSNPs) have emerged as a promising technique for enzyme/protein immobilization via a self-assembly process. Based on the desired application, different sizes and distribution of the polymer–protein CSNPs may be required. This work systematically studies the assembly process of poly(4-vinyl pyridine) and bovine serum albumin CSNPs. Average particle size was controlled by varying the concentrations of each reagent. Particle size and size distributions were monitored by dynamic light scattering, ultra-small-angle X-ray scattering, small-angle X-ray scattering and transmission electron microscopy. Results showed a wide range of CSNPs could be assembled ranging from an average radius as small as 52.3 nm, to particles above 1 µm by adjusting reagent concentrations. In situ X-ray scattering techniques monitored particle assembly as a function of time showing the initial particle growth followed by a decrease in particle size as they reach equilibrium. The results outline a general strategy that can be applied to other CSNP systems to better control particle size and distribution for various applications.

Polymer-Protein Core-Shell Nanoparticles for Enhanced Antigen Immunogenicity

Nanoengineered vaccine platforms can be modeled after viruses and other pathogens with highly organized and repetitive structures that trigger the host immune system. Here we demonstrated a pyridine-grafted poly(ε-caprolactone)-based polymer-protein core-shell nanoparticles (PPCS-NPs) platform can effectively trigger the host immune system and lead to significantly higher antibody titers.

Facile co-assembly process to generate core-shell nanoparticles with functional protein corona

A simple and robust protocol to maintain the structural feature of polymer-protein core-shell nanoparticles (PPCS-NPs) is developed based on the synergistic interactions between proteins and functional polymers. Using the self-assembly method, a broad range of proteins can be assembled to the selective water-insoluble polymers containing pyridine groups. The detailed analysis of the PPCS-NPs structure was conducted using FESEM and thin-sectioned TEM. The results illustrated that the protein molecules are located on the corona of the PPCS-NPs. While proteins are displacing between water and polymer to minimize the interfacial energy, the polymer offers a unique microenvironment to maintain protein structure and conformation. The proposed mechanism is based on a fine balance between hydrophobicity and hydrophilicity, as well as hydrogen bonding between proteins and polymer. The PPCS-NPs can serve as a scaffold to incorporate both glucose oxidase (GOX) and horseradish peroxidase (HRP) onto a single particle. Such a GOX-HRP bienzymatic system showed a ~20% increase in activity in comparison to the mixed free enzymes. Our method therefore provides a unique platform to preserve protein structure and conformation and can be extended to a number of biomolecules.