{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T17:20:20Z","timestamp":1788542420241,"version":"build-2803163510"},"reference-count":45,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T00:00:00Z","timestamp":1774310400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005668","name":"FAPDF","doi-asserted-by":"publisher","award":["00193.00001730\/2022-95"],"award-info":[{"award-number":["00193.00001730\/2022-95"]}],"id":[{"id":"10.13039\/501100005668","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003593","name":"CNPq","doi-asserted-by":"publisher","award":["311982\/2022-0"],"award-info":[{"award-number":["311982\/2022-0"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002322","name":"CAPES","doi-asserted-by":"publisher","award":["001"],"award-info":[{"award-number":["001"]}],"id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>In search of a non-surgical alternative for male animal sterilization, this study investigated the use of gold-coated maghemite nanoparticles (\u03b3-Fe2O3@Au) functionalized with citrate to produce testicular photohyperthermia (PHT). Wistar rats received an intratesticular injection of the fluid containing the nanoparticles (150 \u00b5L\/testicle) followed by testicular irradiation with an LED light (808 nm). Testicular temperature was maintained at ~45 \u00b0C for 15 min. The results demonstrated a significant reduction in testicular volume and weight and sperm motility and normal morphology in PHT-treated animals, together with histopathological degeneration of seminiferous tubules. No treatment-related side effects or signs of systemic toxicity were observed. The biodistribution of the gold (Au) and iron (Fe) from the nanoparticles showed that the testes were the primary site of nanoparticle accumulation until day 56 post-treatment with possible renal excretion of Au. These findings support the prospect of testicular PHT mediated by \u03b3-Fe2O3@Au nanoparticles as a neutering method for male animals.<\/jats:p>","DOI":"10.3390\/molecules31071064","type":"journal-article","created":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T12:58:59Z","timestamp":1774357139000},"page":"1064","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Testicular Photohyperthermia Mediated by Magnetic Nanoparticles: Implications for Male Fertility Control"],"prefix":"10.3390","volume":"31","author":[{"given":"Vanessa N.","family":"Lima","sequence":"first","affiliation":[{"name":"Instituto de Ci\u00eancias Biol\u00f3gicas, Universidade de Bras\u00edlia, Asa Norte, Brasilia 70910-900, DF, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juliana Lis M.","family":"Brito","sequence":"additional","affiliation":[{"name":"Instituto de Ci\u00eancias Biol\u00f3gicas, Universidade de Bras\u00edlia, Asa Norte, Brasilia 70910-900, DF, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-6935-0137","authenticated-orcid":false,"given":"Ana B\u00e1rbara R.","family":"Silva","sequence":"additional","affiliation":[{"name":"Instituto de Ci\u00eancias Biol\u00f3gicas, Universidade de Bras\u00edlia, Asa Norte, Brasilia 70910-900, DF, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aline R. M.","family":"Marangon","sequence":"additional","affiliation":[{"name":"Independent Researcher, Taguatinga 72015-015, DF, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Felipe M.","family":"Pimentel","sequence":"additional","affiliation":[{"name":"Independent Researcher, Brasilia 70684-200, DF, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Breno C. P.","family":"Coelho","sequence":"additional","affiliation":[{"name":"Instituto Federal de Bras\u00edlia, Asa Norte, Brasilia 70830-450, DF, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1210-8329","authenticated-orcid":false,"given":"Marcelo H.","family":"Sousa","sequence":"additional","affiliation":[{"name":"Faculdade de Ci\u00eancias e Tecnologias em Sa\u00fade, Campus Universit\u00e1rio Ceil\u00e2ndia Sul, Universidade de Bras\u00edlia, Ceil\u00e2ndia 72220-275, DF, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rodrigo B.","family":"Nunes","sequence":"additional","affiliation":[{"name":"Instituto de F\u00edsica, Universidade de Bras\u00edlia, Asa Norte, Brasilia 70910-900, DF, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4289-8678","authenticated-orcid":false,"given":"Paulo Eduardo N.","family":"Souza","sequence":"additional","affiliation":[{"name":"Instituto de F\u00edsica, Universidade de Bras\u00edlia, Asa Norte, Brasilia 70910-900, DF, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-0988-7618","authenticated-orcid":false,"given":"Raquel","family":"Pazos","sequence":"additional","affiliation":[{"name":"Centro de Investigaci\u00f3n Cooperativa en Biomateriales (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), 20014 San Sebastian, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sergio E.","family":"Moya","sequence":"additional","affiliation":[{"name":"Centro de Investigaci\u00f3n Cooperativa en Biomateriales (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), 20014 San Sebastian, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7763-0746","authenticated-orcid":false,"given":"Carolina M.","family":"Lucci","sequence":"additional","affiliation":[{"name":"Instituto de Ci\u00eancias Biol\u00f3gicas, Universidade de Bras\u00edlia, Asa Norte, Brasilia 70910-900, DF, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1056","DOI":"10.1016\/j.theriogenology.2011.10.008","article-title":"Permanent Contraception of Dogs Induced with Intratesticular Injection of a Zinc Gluconate-Based Solution","volume":"77","author":"Oliveira","year":"2012","journal-title":"Theriogenology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1186\/s12610-019-0092-8","article-title":"Chemical Sterilization with Intratesticular Administration of Zinc Gluconate in Adult Dogs: A Preliminary Report","volume":"29","author":"Rafatmah","year":"2019","journal-title":"Basic. 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