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To address this problem, we developed and validated a protocol of surface-enhanced Raman spectroscopy (SERS) with silver nanostars for the discrimination of A. baumannii and K. pneumoniae species, and their globally disseminated and clinically relevant antibiotic resistant clones. Isolates were characterized by mixing bacterial colonies with silver nanostars, followed by deposition on filter paper for SERS spectrum acquisition. Spectral data were processed with unsupervised and supervised multivariate data analysis methods, including principal component analysis (PCA) and partial least-squares discriminant analysis (PLSDA), respectively. Our proposed SERS procedure using silver nanostars adsorbed to the bacteria, followed by multivariate data analysis, enabled differentiation between and within species. This pilot study demonstrates the potential of SERS for the rapid discrimination of clinically relevant A. baumannii and K. pneumoniae species and clones, displaying several advantages such as the ease of silver nanostars synthesis and the possible use of a handheld spectrometer, which makes this approach ideal for point-of-care applications.<\/jats:p>","DOI":"10.3390\/bios13020149","type":"journal-article","created":{"date-parts":[[2023,1,18]],"date-time":"2023-01-18T01:33:26Z","timestamp":1674005606000},"page":"149","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Silver Nanostar-Based SERS for the Discrimination of Clinically Relevant Acinetobacter baumannii and Klebsiella pneumoniae Species and Clones"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8621-4701","authenticated-orcid":false,"given":"Miguel Peixoto","family":"de Almeida","sequence":"first","affiliation":[{"name":"LAQV\/REQUIMTE, Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9608-2404","authenticated-orcid":false,"given":"Carla","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"UCIBIO\u2014Applied Molecular Biosciences Unit, Department of Biological Sciences, Laboratory of Microbiology, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal"},{"name":"Associate Laboratory, Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1171-0326","authenticated-orcid":false,"given":"\u00c2ngela","family":"Novais","sequence":"additional","affiliation":[{"name":"UCIBIO\u2014Applied Molecular Biosciences Unit, Department of Biological Sciences, Laboratory of Microbiology, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal"},{"name":"Associate Laboratory, Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal"},{"name":"4TOXRUN, Toxicology Research Unit, University Institute of Health Sciences, CESPU (IUCS-CESPU), 4585-116 Gandra, Portugal"}]},{"given":"Filipa","family":"Grosso","sequence":"additional","affiliation":[{"name":"UCIBIO\u2014Applied Molecular Biosciences Unit, Department of Biological Sciences, Laboratory of Microbiology, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal"},{"name":"Associate Laboratory, Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal"}]},{"given":"Nicolae","family":"Leopold","sequence":"additional","affiliation":[{"name":"Faculty of Physics, Babe\u015f-Bolyai University, 400084 Cluj-Napoca, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5810-8215","authenticated-orcid":false,"given":"Lu\u00edsa","family":"Peixe","sequence":"additional","affiliation":[{"name":"UCIBIO\u2014Applied Molecular Biosciences Unit, Department of Biological Sciences, Laboratory of Microbiology, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal"},{"name":"Associate Laboratory, Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5139-2871","authenticated-orcid":false,"given":"Ricardo","family":"Franco","sequence":"additional","affiliation":[{"name":"Associate Laboratory i4HB\u2014Institute for Health and Bioeconomy, School of Science and Technology, Universidade NOVA de Lisboa, 2819-516 Caparica, Portugal"},{"name":"UCIBIO\u2014Applied Molecular Biosciences Unit, Departamento de Qu\u00edmica, School of Science and Technology, Universidade NOVA de Lisboa, 2819-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2086-5696","authenticated-orcid":false,"given":"Eul\u00e1lia","family":"Pereira","sequence":"additional","affiliation":[{"name":"LAQV\/REQUIMTE, Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias, Universidade do Porto, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Badescu, B., Buda, V., Romanescu, M., Lombrea, A., Danciu, C., Dalleur, O., Dohou, A., Dumitrascu, V., Cretu, O., and Licker, M. 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