{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T01:24:41Z","timestamp":1772760281173,"version":"3.50.1"},"reference-count":49,"publisher":"AIP Publishing","issue":"4","funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["2022374"],"award-info":[{"award-number":["2022374"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002701","name":"Ministry of Education","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100002701","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS-2023-00259957"],"award-info":[{"award-number":["RS-2023-00259957"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2024,1,28]]},"abstract":"<jats:p>Transferrin, a central player in iron transport, has been recognized not only for its role in binding iron but also for its interaction with other metals, including titanium. This study employs solid-state nanopores to investigate the binding of titanium ions [Ti(IV)] to transferrin in a single-molecule and label-free manner. We demonstrate the novel application of solid-state nanopores for single-molecule discrimination between apo-transferrin (metal-free) and Ti(IV)-transferrin. Despite their similar sizes, Ti(IV)-transferrin exhibits a reduced current drop, attributed to differences in translocation times and filter characteristics. Single-molecule analysis reveals Ti(IV)-transferrin\u2019s enhanced stability and faster translocations due to its distinct conformational flexibility compared to apo-transferrin. Furthermore, our study showcases solid-state nanopores as real-time monitors of biochemical reactions, tracking the gradual conversion of apo-transferrin to Ti(IV)-transferrin upon the addition of titanium citrate. This work offers insights into Ti(IV) binding to transferrin, promising applications for single-molecule analysis and expanding our comprehension of metal\u2013protein interactions at the molecular level.<\/jats:p>","DOI":"10.1063\/5.0185590","type":"journal-article","created":{"date-parts":[[2024,1,26]],"date-time":"2024-01-26T10:45:00Z","timestamp":1706265900000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":5,"title":["Real-time monitoring of Ti(IV) metal ion binding of transferrin using a solid-state nanopore"],"prefix":"10.1063","volume":"160","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5634-8239","authenticated-orcid":false,"given":"Matthew","family":"O\u2019Donohue","sequence":"first","affiliation":[{"name":"Applied Science Program, Southern Methodist University 1 , Dallas, Texas 75205, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-6896-3112","authenticated-orcid":false,"given":"Madhav L.","family":"Ghimire","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Southern Methodist University 2 , 3101 Dyer Street, Dallas, Texas 75205, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7961-3904","authenticated-orcid":false,"given":"Sangyoup","family":"Lee","sequence":"additional","affiliation":[{"name":"Bionic Research Center, Biomedical Research Division, Korea Institute of Science and Technology 3 , Seoul, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0819-1644","authenticated-orcid":false,"given":"Min Jun","family":"Kim","sequence":"additional","affiliation":[{"name":"Applied Science Program, Southern Methodist University 1 , Dallas, Texas 75205, USA"},{"name":"Department of Mechanical Engineering, Southern Methodist University 2 , 3101 Dyer Street, Dallas, Texas 75205, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"317","published-online":{"date-parts":[[2024,1,26]]},"reference":[{"key":"2024012610445416400_c1","first-page":"164","article-title":"Review on iron and its importance for human health","volume":"19","year":"2014","journal-title":"J. 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