{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T10:19:13Z","timestamp":1787566753015,"version":"build-2736575974"},"reference-count":37,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T00:00:00Z","timestamp":1787529600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research, Development, and Innovation Office-NKFIH","award":["PD137938"],"award-info":[{"award-number":["PD137938"]}]},{"award":["PD137938"],"award-info":[{"award-number":["PD137938"]}],"id":[{"id":"https:\/\/ror.org\/03g2am276","id-type":"ROR","asserted-by":"publisher"}]},{"name":"J\u00e1nos Bolyai Research Scholarship"},{"name":"Hungarian Academy of Science","award":["KGYNK2025-40"],"award-info":[{"award-number":["KGYNK2025-40"]}]},{"award":["KGYNK2025-40"],"award-info":[{"award-number":["KGYNK2025-40"]}],"id":[{"id":"https:\/\/ror.org\/02ks8qq67","id-type":"ROR","asserted-by":"publisher"}]},{"name":"University of Szeged OA Grant","award":["9014"],"award-info":[{"award-number":["9014"]}]},{"award":["9014"],"award-info":[{"award-number":["9014"]}],"id":[{"id":"https:\/\/ror.org\/01pnej532","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>In this paper, we report a metal-driven structural tuning strategy with the L-histidine (His) ligand to modulate peroxidase-like nanozyme performance. Although the His coordinates with gold(III) ions to form an extended helical coordination polymer, its interaction with Cu(II) ions results in quantum-confined, ultrasmall nanoclusters. Based on the optical, structural, and surface analysis, the blue-emitting cores are stabilized by His ligands through imidazole nitrogen coordination, consistent with a Cu-centered coordination environment involved in the observed catalytic activity. According to the catalytic measurements, the His-Cu clusters outperformed the His-Au coordination polymer reference system. Steady-state kinetic modeling and 3D profiling revealed a pronounced shift in the pH optimum: low-valent Cu-containing His-Cu NCs enable efficient peroxide-dependent catalysis under nearly neutral conditions (pH 7.4), whereas His-Au CP exhibits its maximum activity under acidic conditions. Based on these findings, this work highlights nanoscale engineering for tailor-made biomimetic applications.<\/jats:p>","DOI":"10.3390\/nano16171052","type":"journal-article","created":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T08:03:41Z","timestamp":1787558621000},"page":"1052","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Controlling pH-Dependent Nanozyme Activity by Metal Identity in Histidine-Based Nanoarchitectures"],"prefix":"10.3390","volume":"16","author":[{"given":"Zsolt M.","family":"Horv\u00e1th","sequence":"first","affiliation":[{"name":"Department of Physical Chemistry and Materials Science, University of Szeged, Rerrich B. Sq. 1, H-6720 Szeged, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-4344-5877","authenticated-orcid":false,"given":"\u00c1rp\u00e1d","family":"Turcs\u00e1nyi","sequence":"additional","affiliation":[{"name":"MTA-SZTE Lend\u00fclet \u201cMomentum\u201d Noble Metal Nanostructures Research Group, University of Szeged, Rerrich B. Sq. 1, H-6720 Szeged, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6980-9524","authenticated-orcid":false,"given":"Edit","family":"Csap\u00f3","sequence":"additional","affiliation":[{"name":"Department of Physical Chemistry and Materials Science, University of Szeged, Rerrich B. Sq. 1, H-6720 Szeged, Hungary"},{"name":"MTA-SZTE Lend\u00fclet \u201cMomentum\u201d Noble Metal Nanostructures Research Group, University of Szeged, Rerrich B. 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