{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,13]],"date-time":"2025-11-13T18:31:27Z","timestamp":1763058687465,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,1,24]],"date-time":"2022-01-24T00:00:00Z","timestamp":1642982400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UID\/NEU\/04539\/2019","UIDB\/04539\/2020","UIDP\/04539\/2020","UIDB\/00313\/2020","UIDP\/QUI\/00313\/2020"],"award-info":[{"award-number":["UID\/NEU\/04539\/2019","UIDB\/04539\/2020","UIDP\/04539\/2020","UIDB\/00313\/2020","UIDP\/QUI\/00313\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"COMPETE-FEDER","award":["POCI-01-0145-FEDER-007440"],"award-info":[{"award-number":["POCI-01-0145-FEDER-007440"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Direct pulp capping consists of a procedure in which a material is directly placed over the exposed pulp to maintain dental vitality. Although still widely used in clinical practice, previous in vitro studies found that the biomaterial Life\u00ae presented high cytotoxicity, leading to cell death. This study aimed to identify the Life\u00ae constituents responsible for its cytotoxic effects on odontoblast-like cells (MDPC-23). Aqueous medium conditioned with Life\u00ae was subjected to liquid\u2013liquid extraction with ethyl acetate. After solvent removal, cells were treated with residues isolated from the organic and aqueous fractions. MTT and Trypan blue assays were carried out to evaluate the metabolic activity and cell death. The organic phase residue promoted a significant decrease in metabolic activity and increased cell death. On the contrary, no cytotoxic effects were observed with the mixture from the aqueous fraction. Spectroscopic and spectrometric methods allowed the identification of the toxic compounds. A mixture of the regioisomers ortho, para, and meta of N-ethyl-toluenesulfonamide was identified as the agent responsible for the toxicity of biomaterial Life\u00ae in MDPC-23 cells. These findings contribute to improving biomaterial research and development.<\/jats:p>","DOI":"10.3390\/ma15030871","type":"journal-article","created":{"date-parts":[[2022,1,25]],"date-time":"2022-01-25T20:40:18Z","timestamp":1643143218000},"page":"871","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Isolation and Identification of Cytotoxic Compounds Present in Biomaterial Life\u00ae"],"prefix":"10.3390","volume":"15","author":[{"given":"Maria Beatriz","family":"Ferreira","sequence":"first","affiliation":[{"name":"Institute of Integrated Clinical Practice, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1891-9010","authenticated-orcid":false,"given":"Nelson A. M.","family":"Pereira","sequence":"additional","affiliation":[{"name":"Coimbra Chemistry Centre (CQC)-Institute of Molecular Sciences (IMS) and Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9269-5417","authenticated-orcid":false,"given":"Carlos Miguel","family":"Marto","sequence":"additional","affiliation":[{"name":"Institute of Experimental Pathology, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"},{"name":"Institute of Biophysics, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"},{"name":"Coimbra Institute for Clinical and Biomedical Research (iCBR), Area of Environment, Genetics and Oncobiology (CIMAGO), Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"},{"name":"Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal"},{"name":"Clinical Academic Center of Coimbra (CACC), 3000-354 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9170-4334","authenticated-orcid":false,"given":"Miguel","family":"Cardoso","sequence":"additional","affiliation":[{"name":"Institute of Integrated Clinical Practice, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"},{"name":"Institute of Biophysics, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"}]},{"given":"In\u00eas","family":"Amaro","sequence":"additional","affiliation":[{"name":"Institute of Integrated Clinical Practice, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2924-7926","authenticated-orcid":false,"given":"Ana","family":"Coelho","sequence":"additional","affiliation":[{"name":"Institute of Integrated Clinical Practice, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"},{"name":"Coimbra Institute for Clinical and Biomedical Research (iCBR), Area of Environment, Genetics and Oncobiology (CIMAGO), Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"},{"name":"Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal"},{"name":"Clinical Academic Center of Coimbra (CACC), 3000-354 Coimbra, Portugal"}]},{"given":"Jos\u00e9","family":"Saraiva","sequence":"additional","affiliation":[{"name":"Institute of Integrated Clinical Practice, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3769-9786","authenticated-orcid":false,"given":"Gianrico","family":"Spagnuolo","sequence":"additional","affiliation":[{"name":"Department of Neurosciences, Reproductive and Odontostomatological Sciences, University of Naples \u201cFederico II\u201d, 80125 Napoli, Italy"},{"name":"Institute of Dentistry, I. M. Sechenov First Moscow State Medical University, 119146 Moscow, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5968-6161","authenticated-orcid":false,"given":"Manuel","family":"Marques Ferreira","sequence":"additional","affiliation":[{"name":"Coimbra Institute for Clinical and Biomedical Research (iCBR), Area of Environment, Genetics and Oncobiology (CIMAGO), Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"},{"name":"Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3000-548 Coimbra, Portugal"},{"name":"Clinical Academic Center of Coimbra (CACC), 3000-354 Coimbra, Portugal"},{"name":"Institute of Endodontics, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7460-3758","authenticated-orcid":false,"given":"Marta","family":"Pi\u00f1eiro","sequence":"additional","affiliation":[{"name":"Coimbra Chemistry Centre (CQC)-Institute of Molecular Sciences (IMS) and Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3256-4954","authenticated-orcid":false,"given":"Teresa M. 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