{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T16:12:30Z","timestamp":1787328750215,"version":"build-2736575974"},"reference-count":53,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,22]],"date-time":"2022-12-22T00:00:00Z","timestamp":1671667200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior (CAPES\u2014Brazil)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>This study aimed to achieve bioactivity on the PEEK surface using piranha solution through a lower functionalization time. For this purpose, the functionalization occurred with piranha solution and 98% sulfuric acid in the proportions of 1:2, 1:1, and 2:1 at periods of 30, 60, and 90 s. The samples treated for longer times at higher concentrations registered the characteristic spectroscopy band associated with sulfonation. Additionally, both chemical treatments allowed the opening of the aromatic ring, increasing the number of functional groups available and making the surface more hydrophilic. The piranha solution treatments with higher concentrations and longer times promoted greater heterogeneity in the surface pores, which affected the roughness of untreated PEEK. Furthermore, the treatments induced calcium deposition on the surface during immersion in SBF fluid. In conclusion, the proposed chemical modifications using sulfuric acid SPEEK 90 and, especially, the piranha solution PEEK-PS 2:1-90, were demonstrated to be promising in promoting the rapid bioactivation of PEEK-based implants.<\/jats:p>","DOI":"10.3390\/molecules28010074","type":"journal-article","created":{"date-parts":[[2022,12,23]],"date-time":"2022-12-23T03:26:25Z","timestamp":1671765985000},"page":"74","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Use of Piranha Solution as An Alternative Route to Promote Bioactivation of PEEK Surface with Low Functionalization Times"],"prefix":"10.3390","volume":"28","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9481-2231","authenticated-orcid":false,"given":"Flavia Suzany Ferreira dos","family":"Santos","sequence":"first","affiliation":[{"name":"Department of Materials Engineering, Federal University of Campina Grande, Campina Grande, PB 58429-900, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3916-6214","authenticated-orcid":false,"given":"Jos\u00e9 Filipe Bacalhau","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering, Federal University of Campina Grande, Campina Grande, PB 58429-900, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Milena Costa","family":"da Silva","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering, Federal University of Campina Grande, Campina Grande, PB 58429-900, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2319-7371","authenticated-orcid":false,"given":"Maria Eduarda Vasconcelos","family":"Barreto","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering, Federal University of Campina Grande, Campina Grande, PB 58429-900, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1947-0075","authenticated-orcid":false,"given":"Henrique Nunes","family":"da Silva","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering, Federal University of Campina Grande, Campina Grande, PB 58429-900, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2073-0989","authenticated-orcid":false,"given":"Su\u00e9dina Maria","family":"de Lima Silva","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering, Federal University of Campina Grande, Campina Grande, PB 58429-900, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcus Vinicius Lia","family":"Fook","sequence":"additional","affiliation":[{"name":"Department of Materials Engineering, Federal University of Campina Grande, Campina Grande, PB 58429-900, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kurtz, S.M. 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