Gold nanostars coated with a mesoporous silica shell and functionalized with poly(ethylene glycol) containing photolabile 2-nitrobenzyl moieties are able to release doxorubicin after NIR light irradiation at low power irradiance via a multiphoton absorption photo-dissociation process.

(1) Background: The ability of metal nanoparticles to carry other molecules and their electromagnetic interactions can be used for localized drug release or to heat malignant tissue, as in the case of photothermal treatments. Plasmonics can be used to calculate their absorption and electric field enhancement, which can be further used to predict the outcome of photothermal experiments. In this study, we model the nanoparticle geometry in a Finite Element Model calculus environment to calculate the effects that occur as a response to placing it in an optical, electromagnetic field, and also a model of the experimental procedure to measure the temperature rise while irradiating a suspension of nanoparticles. (2) Methods: Finite Element Method numerical models using the COMSOL interface for geometry and mesh generation and iterative solving discretized Maxwell’s equations; (3) Results: Absorption and scattering cross-section spectrums were obtained for NanoRods and NanoStars, also varying their geometry as a parameter, along with electric field enhancement in their surroundings; temperature curves were calculated and measured as an outcome of the irradiation of different concentration suspensions; (4) Conclusions: The results obtained are comparable with the bibliography and experimental measurements.

In this work, fluorogenic probes based on oligonucleotide capped nanoporous anodic alumina films are developed for specific and sensitive detection of human papilloma virus (HPV) DNA. The probe consists of anodic alumina nanoporous films loaded with the fluorophore rhodamine B (RhB) and capped with oligonucleotides bearing specific base sequences complementary to genetic material of different high‐risk (hr) HPV types. Synthesis protocol is optimized for scale up production of sensors with high reproducibility. The sensors' surfaces are characterized by scanning electron microscopy (HR‐FESEM) and atomic force microscopy (AFM) and their atomic composition is determined by energy dispersive X‐ray spectroscopy (EDXS). Oligonucleotide molecules onto nanoporous films block the pores and avoid diffusion of RhB to the liquid phase. Pore opening is produced when specific DNA of HPV is present in the medium, resulting in RhB delivery, that is detected by fluorescence measurements. The sensing assay is optimized for reliable fluorescence signal reading. Nine different sensors are synthesized for specific detection of 14 different hr‐HPV types in clinical samples with very high sensitivity (100%) and high selectivity (93–100%), allowing rapid screening of virus infections with very high negative predictive values (100%).

The COVID‐19 pandemic, which began in 2019, has highlighted the importance of testing and tracking infected individuals as a means of mitigating the spread of the virus. In this context, the development of sensitive and rapid methods for the detection of SARS‐CoV‐2, the virus responsible for COVID‐19, is crucial. Herein, a biosensor based on oligonucleotide‐gated nanomaterials for the specific detection of SARS‐CoV‐2 spike protein is presented. The sensing system consists of a nanoporous anodic alumina disk loaded with the fluorescent indicator rhodamine B and capped with a DNA aptamer that selectively binds the SARS‐CoV‐2 spike protein. The system is initially evaluated using pseudotype virus systems based on vesicular stomatitis virus carrying different SARS‐CoV‐2 S‐proteins on their surface. When the pseudotype virus is present, the cap of the solid is selectively removed, triggering the release of the dye from the pore voids to the medium. The nanodevice demonstrated its ability to detect pseudotype virus concentrations as low as 7.5·10³ PFU mL. In addition, the nanodevice is tested on nasopharyngeal samples from individuals suspected of having COVID‐19.