Yurena Luengo

The efficient and safe intracellular delivery of CRISPR ribonucleoproteins (RNPs) remains a major challenge for the development of genome editing strategies. Magnetic iron oxide nanoparticles (MNPs) offer an attractive and biocompatible delivery platform. However, their use for the delivery of functional CRISPR RNPs remains comparatively underexplored. Here, we developed carboxymethyl dextran (CMD)-coated MNPs as non-viral carriers for Cas9 and Cas12a RNPs. Nanocomplexes were formed through electrostatic interactions, without the need for chemical coupling reagents or additional surface functionalization. Both RNPs efficiently associated with MNPs, and the resulting nanocomplexes exhibited stable physicochemical properties and retained their cargo in serum-supplemented culture medium for up to 24 hours. Cellular uptake was confirmed by microscopy, while biocompatibility assays revealed no overt cytotoxicity. Functional genome editing was demonstrated at reporter and endogenous gene loci in HEK-293T cells, as well as in primary human dermal fibroblasts. Finally, we explored the therapeutic potential of this platform for recessive dystrophic epidermolysis bullosa (RDEB) by targeting COL7A1 exon 80, with the aim of removing the prevalent c.6527insC mutation while preserving the reading frame. Cas9 RNP nanocomplexes enabled exon 80 deletion. These findings establish CMD-coated MNPs as a versatile platform for the delivery of Cas9 and Cas12a RNPs and support further investigation of magnetic nanoparticle-mediated genome editing for inherited skin disorders.

Densely packed arrays of monodisperse dielectric spheres exhibit strong optical diffraction down to the single‐layer limit, making them highly attractive for the implementation of order‐ and disorder‐based functionalities in photonic devices. Colloidal techniques are among the most convenient methods for creating these densely packed arrays, performing well on flat substrates. However, forming complex geometries with colloidal techniques usually requires patterned substrates and postprocessing routes. Here, a facile colloidal route capable of producing a complex configuration with two levels of functionality is described. Specifically, by foaming and casting colloidal suspensions of monodisperse spherical particles, both ordered and disordered arrays of densely packed spheres on unpatterned flat substrates are achieved. These arrays outline a complex cellular configuration consisting of a ridge‐trough network structure that supports random lasing action at the macroscale, while enabling Bragg diffraction (order) or Mie scattering (disorder) across the visible and near‐infrared spectral ranges at the microscale. Notably, the optical properties of the disordered foams can be effectively modeled using Mie calculations for individual spheres, serving as a valuable proof of concept for developing particulate portable detectors based on Mie resonances and a hierarchical configuration built upon a simple self‐assembly process carried out on flat substrates.

The clinical implementation of magnetic hyperthermia has experienced little progress since the first clinical trial was completed in 2005. Some of the hurdles to overcome are the reliable production of magnetic nanoparticles with controlled properties and the control of the temperature at the target tissue in vivo. Here, forty samples of iron oxide superparamagnetic nanoparticles were prepared by similar methods and thoroughly characterized in terms of size, aggregation degree, and heating response. Selected samples were intratumorally administered in animals with subcutaneous xenografts of human pancreatic cancer. In vivo experiments showed that it is possible to control the rise in temperature by modulating the field intensity during in vivo magnetic hyperthermia protocols. The procedure does not require sophisticated materials and it can be easily implemented by researchers or practitioners working in magnetic hyperthermia therapies.

Magnetic nanoparticles (MNP) are employed as nanocarriers and in magnetic hyperthermia (MH) for the treatment of cancers. Herein, a smart drug delivery system composed of MNP functionalized with the cytotoxic drug gemcitabine (MNP-GEM) has been thoroughly evaluated. The linker employed is based on a disulfide bond and allows the controlled release of GEM under a highly reducing environment, which is frequently present in the cytoplasm of tumor cells. The stability, MH, and the interaction with plasma proteins of the nanoparticles are evaluated, highlighting their great potential for biological applications. Their cytotoxicity is assessed in three pancreatic cancer cell lines with different sensitivity to GEM, including the generation of reactive oxygen species (ROS), the effects on the cell cycle, and the mechanisms of cell death involved. Remarkably, the proposed nanocarrier is better internalized than unmodified nanoparticles, and it is particularly effective in PANC-1 cells, resistant to GEM, but not in non-tumoral keratinocytes. Additionally, its combination with MH produces a synergistic cytotoxic effect in all cancer cell lines tested. In conclusion, MNP-GEM presents a promising potential for treating pancreatic cancer, due to multiple parameters, such as reduced binding to plasma proteins, increased internalization, and synergistic activity when combined with MH.