{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T00:32:26Z","timestamp":1778718746058,"version":"3.51.4"},"reference-count":49,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,1,26]],"date-time":"2022-01-26T00:00:00Z","timestamp":1643155200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"MUR (Ministero dell\u2019Universit\u00e0 e della Ricerca, Rome, Italy)","award":["DELPHI projects through the program \u201cDipartimenti di Eccellenza 2018-2022\u201d"],"award-info":[{"award-number":["DELPHI projects through the program \u201cDipartimenti di Eccellenza 2018-2022\u201d"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Enhancing the antibacterial activity of old antibiotics by a multitarget approach, such as combining antibiotics with metal nanoparticles, is a valuable strategy to overcome antibacterial resistance. In this work, the synergistic antimicrobial effect of silver nanoparticles and antibiotics, immobilized on a solid support, was investigated. Nanometric layered double hydroxides (LDH) based on Zn(II) and Al(III) were prepared by the double microemulsion technique. The dual function of LDH as an anionic exchanger and support for metal nanoparticles was exploited to immobilize both silver and antibiotics. Cefazolin (CFZ), a \u03b2-lactam, and nalidixic acid (NAL), a quinolone, were selected and intercalated into LDH obtaining ZnAl-CFZ and ZnAl-NAL samples. These samples were used for the growth of silver nanoparticles with dimension ranging from 2.5 to 8 nm. Silver and antibiotics release profiles, from LDH loaded with antibiotics and Ag\/antibiotics, were evaluated in two different media: water and phosphate buffer. Interestingly, the release profiles are affected by both the acceptor media and the presence of silver. The synergistic antibacterial activity of LDH containing both silver and antibiotics were investigated on gram-positives (Staphylococcus aureus and Streptococcus pneumoniae) and gram-negatives (Pseudomonas aeruginosa) and compared with the plain antimicrobials and LDH containing only antibiotics or silver.<\/jats:p>","DOI":"10.3390\/ma15030932","type":"journal-article","created":{"date-parts":[[2022,1,26]],"date-time":"2022-01-26T11:02:53Z","timestamp":1643194973000},"page":"932","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Overcoming Antibiotic Resistance: Playing the \u2018Silver Nanobullet\u2019 Card"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2927-1130","authenticated-orcid":false,"given":"Morena","family":"Nocchetti","sequence":"first","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo, 1, 06123 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1495-6674","authenticated-orcid":false,"given":"Elisa","family":"Boccalon","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Salerno, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9121-7875","authenticated-orcid":false,"given":"Monica","family":"Pica","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo, 1, 06123 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nicoletta Maria Rosaria","family":"Giordano","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo, 1, 06123 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4525-7937","authenticated-orcid":false,"given":"Francesco","family":"Finori","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Biology and Biotechnology, University of Perugia, Via Elce di Sotto, 8, 06123 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1572-4290","authenticated-orcid":false,"given":"Donatella","family":"Pietrella","sequence":"additional","affiliation":[{"name":"Microbiology and Clinical Microbiology, Department of Medicine and Surgery, University of Perugia, Piazzale Gambuli, 1, 06129 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio","family":"Cipiciani","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Biology and Biotechnology, University of Perugia, Via Elce di Sotto, 8, 06123 Perugia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"S71","DOI":"10.1093\/cid\/ciu392","article-title":"The future of antibiotics and resistance: A tribute to a career of leadership by John Bartlett","volume":"59","author":"Spellberg","year":"2014","journal-title":"Clin. 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