{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T11:21:35Z","timestamp":1771068095675,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2020,11,14]],"date-time":"2020-11-14T00:00:00Z","timestamp":1605312000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Superparamagnetic nanoparticles (iron oxide nanoparticles\u2014IONs) are suitable for hyperthermia after irradiating with radiofrequency radiation. Concerning the suitability for laser ablation, IONs present a low molar absorption coefficient in the near-infrared region close to 800 nm. For this reason, they are combined with other photothermal agents into a hybrid composite. Here, we show that IONs absorb and convert into heat the infrared radiation characteristic of the so-called second-biological window (1000\u20131350 nm) and, in consequence, they can be used for thermal ablation in such wavelengths. To the known excellent water solubility, colloidal stability and biocompatibility exhibited by IONs, an outstanding photothermal performance must be added. For instance, a temperature increase of 36 \u00b0C was obtained after irradiating at 8.7 W cm\u22122 for 10 min a suspension of IONs at iron concentration of 255 mg L\u22121. The photothermal conversion efficiency was ~72%. Furthermore, IONs showed high thermogenic stability during the whole process of heating\/cooling. To sum up, while the use of IONs in the first bio-window (700\u2013950 nm) presents some concerns, they appear to be good photothermal agents in the second biological window.<\/jats:p>","DOI":"10.3390\/molecules25225315","type":"journal-article","created":{"date-parts":[[2020,11,16]],"date-time":"2020-11-16T22:53:52Z","timestamp":1605567232000},"page":"5315","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Superparamagnetic Nanoparticles with Efficient Near-Infrared Photothermal Effect at the Second Biological Window"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6232-9886","authenticated-orcid":false,"given":"Maria Ant\u00f2nia","family":"Busquets","sequence":"first","affiliation":[{"name":"Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Universitat de Barcelona, Avda Joan XXIII, 27-31, 08028 Barcelona, Catalonia, Spain"},{"name":"Institut de Nanoci\u00e8ncia i Nanotecnologia (IN<sup>2<\/sup>UB), Universitat de Barcelona, 08028 Barcelona, Catalonia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9923-1997","authenticated-orcid":false,"given":"Juan Marcos","family":"Fern\u00e1ndez-Pradas","sequence":"additional","affiliation":[{"name":"Institut de Nanoci\u00e8ncia i Nanotecnologia (IN<sup>2<\/sup>UB), Universitat de Barcelona, 08028 Barcelona, Catalonia, Spain"},{"name":"Department of Applied Physics, Universitat de Barcelona, Mart\u00ed i Franqu\u00e8s 1, 08028 Barcelona, Catalonia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0676-1447","authenticated-orcid":false,"given":"Pedro","family":"Serra","sequence":"additional","affiliation":[{"name":"Institut de Nanoci\u00e8ncia i Nanotecnologia (IN<sup>2<\/sup>UB), Universitat de Barcelona, 08028 Barcelona, Catalonia, Spain"},{"name":"Department of Applied Physics, Universitat de Barcelona, Mart\u00ed i Franqu\u00e8s 1, 08028 Barcelona, Catalonia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joan","family":"Estelrich","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, Pharmaceutical Technology and Physical Chemistry, Universitat de Barcelona, Avda Joan XXIII, 27-31, 08028 Barcelona, Catalonia, Spain"},{"name":"Institut de Nanoci\u00e8ncia i Nanotecnologia (IN<sup>2<\/sup>UB), Universitat de Barcelona, 08028 Barcelona, Catalonia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"459","DOI":"10.1615\/CritRevBiomedEng.v34.i6.20","article-title":"Thermal therapy, part 1: An introduction to thermal therapy","volume":"34","author":"Habash","year":"2006","journal-title":"Crit. 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