Does the Abiotic Formation of Oligopeptides on TiO2 Nanoparticles Require Special Catalytic Sites? Apparently Not

<div>Preprint version of the paper:</div><div>Does the Abiotic Formation of Oligopeptides on TiO2Nanoparticles Require Special Catalytic Sites? Apparently Not</div><div>by:</div><div>Marco Fabbiani, Marco Pazzi, Marco Vincenti, Gloria Tabacchi, Ettore Fois, Gianmario Martra<br></div><div><br></div><div>Published on 1st August 2018 in:</div><div><a href="https://www.ingentaconnect.com/content/asp/jnn">Journal of Nanoscience and Nanotechnology</a>, 2018, 18, 5854-5857<br></div><div><br></div>The oligomerization of non-activated amino acids catalyzed by nanostrucrured mineral oxide surfaces holds promises as a sustainable route for the industrial production of polypeptides. To analyze the influence of the surface type on the catalytic process, we performed, via a mild Chemical Vapor Deposition approach, the oligomerization of Glycine on two samples of TiO2 nanoparticles characterized by different relative amounts of defective surface terminations. Based on infrared spectroscopy and mass spectrometry data, we show herein that the formation of peptide bonds on titania nanoparticles does not require highly energetic surface terminations, but can occur also on the most abundant and thermodynamically most stable {101} facets of nanosized anatase

Energy Transfer from Magnetic Iron Oxide Nanoparticles: Implications for Magnetic Hyperthermia

ACS Appl. Nano Mater. 2023, 6, 12914–12921https://doi.org/10.1021/acsanm.3c01643Magnetic iron oxide nanoparticles (IONPs) have gained momentum in the field of biomedical applications. They can be remotely heated via alternating magnetic fields, and such heat can be transferred from the IONPs to the local environment. However, the microscopic mechanism of heat transfer is still debated. By X-ray total scattering experiments and first-principles simulations, we show how such heat transfer can occur. After establishing structural and microstructural properties of the maghemite phase of the IONPs, we built a maghemite model functionalized with aminoalkoxysilane, a molecule used to anchor (bio)molecules to oxide surfaces. By a linear response theory approach, we reveal that a resonance mechanism is responsible for the heat transfer from the IONPs to the surroundings. Heat transfer occurs not only via covalent linkages with the IONP but also through the solvent hydrogen-bond network. This result may pave the way to exploit the directional control of the heat flow from the IONPs to the anchored molecules─i.e., antibiotics, therapeutics, and enzymes─for their activation or release in a broader range of medical and industrial applications.</p