{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T09:02:45Z","timestamp":1785488565993,"version":"3.56.0"},"reference-count":33,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T00:00:00Z","timestamp":1785456000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FINEP Materiais Avan\u00e7ados \u2013 Projeto BioAgNPLED","award":["01.22.0200.0\u2014REF. 0161\/2021"],"award-info":[{"award-number":["01.22.0200.0\u2014REF. 0161\/2021"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Acinetobacter baumannii is a microorganism of major global clinical importance, whose carbapenem-resistant phenotype is considered a priority target for the development of new antimicrobial agents. Carbapenem-resistant A. baumannii is associated with healthcare-associated infections and exhibits high mortality rates, prolonged hospital stays, and extensive use of intensive care units. As a control strategy, green-synthesized silver nanoparticles have gained increasing attention. Based on this, the aim of this study was to synthesize a novel triphasic silver nanocomposite, characterize it, and evaluate its antibacterial activity against extensively drug-resistant and pan-drug-resistant isolates. The nanocomposite was synthesized using cell-free bacterial supernatant and was physicochemically characterized regarding concentration, size, morphology, and crystallinity. Its antibacterial activity was assessed using broth microdilution and time\u2013kill assays, followed by toxicity assays using human erythrocytes. A nanoscale and stable nanocomposite was obtained and was composed of metallic silver, silver chloride, and silver phosphate, which exhibited antibacterial activity against all tested isolates. In the toxicity assay, the nanocomposite demonstrated low toxicity and a high selectivity index. These findings demonstrate that Ag\/AgCl\/Ag3PO4 nanocomposite exhibits strong activity against resistant phenotypes for which therapeutic options are limited, highlighting its potential as a control strategy against this pathogen.<\/jats:p>","DOI":"10.3390\/microorganisms14081682","type":"journal-article","created":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T08:20:18Z","timestamp":1785486018000},"page":"1682","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Novel Ag\/AgCl\/Ag3PO4 Nanocomposite Demonstrates Potent Antibacterial Activity Against Multidrug-Resistant and Pan-Resistant Pathogenic Isolates of Acinetobacter baumannii"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1033-3442","authenticated-orcid":false,"given":"Victor Hugo","family":"Montini","sequence":"first","affiliation":[{"name":"Laboratory of Basic and Applied Bacteriology, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-1015-9616","authenticated-orcid":false,"given":"Laura Santana","family":"Buso","sequence":"additional","affiliation":[{"name":"Laboratory of Basic and Applied Bacteriology, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9732-3807","authenticated-orcid":false,"given":"Anast\u00e1cia Nikolaos","family":"Deonas","sequence":"additional","affiliation":[{"name":"Laboratory of Basic and Applied Bacteriology, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriel Henrique Maximino","family":"Santos","sequence":"additional","affiliation":[{"name":"Laboratory of Basic and Applied Bacteriology, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9958-9112","authenticated-orcid":false,"given":"Bruna Carolina","family":"Gon\u00e7alves","sequence":"additional","affiliation":[{"name":"Laboratory of Basic and Applied Bacteriology, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Luiza Francisconi Lubanco","family":"Thom\u00e9","sequence":"additional","affiliation":[{"name":"Laboratory of Basic and Applied Bacteriology, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8593-5849","authenticated-orcid":false,"given":"Paulo Rog\u00e9rio Catarini da","family":"Silva","sequence":"additional","affiliation":[{"name":"Laboratory of X-Ray Analysis, Multiuser Research Laboratory Center, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diego Prudencio dos","family":"Santos","sequence":"additional","affiliation":[{"name":"Department of Chemistry, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cesar Ricardo Teixeira","family":"Tarley","sequence":"additional","affiliation":[{"name":"Department of Chemistry, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1556-5146","authenticated-orcid":false,"given":"Admilton Gon\u00e7alves de","family":"Oliveira","sequence":"additional","affiliation":[{"name":"Laboratory of Microbial Biotechnology, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2579-0048","authenticated-orcid":false,"given":"Danielle Lazarin","family":"Bid\u00f3ia","sequence":"additional","affiliation":[{"name":"Department of Clinical Analysis and Biomedicine, State University of Maring\u00e1, P.O. Box 10.011, Maring\u00e1 87020-900, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7170-2155","authenticated-orcid":false,"given":"Renata Katsuko Takayama","family":"Kobayashi","sequence":"additional","affiliation":[{"name":"Laboratory of Basic and Applied Bacteriology, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3299-4165","authenticated-orcid":false,"given":"Gerson","family":"Nakazato","sequence":"additional","affiliation":[{"name":"Laboratory of Basic and Applied Bacteriology, State University of Londrina, P.O. Box 10.011, Londrina 86057-970, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1016\/S0140-6736(21)02724-0","article-title":"Global burden of bacterial antimicrobial resistance in 2019: A systematic analysis","volume":"399","author":"Murray","year":"2022","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Poudel, A.N., Zhu, S., Cooper, N., Little, P., Tarrant, C., Hickman, M., and Yao, G. (2023). The economic burden of antibiotic resistance: A systematic review and meta-analysis. PLoS ONE, 18.","DOI":"10.1371\/journal.pone.0285170"},{"key":"ref_3","first-page":"100561","article-title":"The burden of antimicrobial resistance in the Americas in 2019: A cross-country systematic analysis","volume":"25","author":"Aguilar","year":"2023","journal-title":"Lancet Reg. 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