{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T07:16:54Z","timestamp":1788419814073,"version":"build-2803163510"},"reference-count":44,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T00:00:00Z","timestamp":1788307200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T00:00:00Z","timestamp":1788307200000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council of Canada","doi-asserted-by":"publisher","award":["RGPIN\u20102020\u201006401"],"award-info":[{"award-number":["RGPIN\u20102020\u201006401"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22176075"],"award-info":[{"award-number":["22176075"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22476072"],"award-info":[{"award-number":["22476072"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22576024"],"award-info":[{"award-number":["22576024"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012226","name":"Fundamental Research Funds for the Central Universities","doi-asserted-by":"publisher","award":["DUT25RC(3)033"],"award-info":[{"award-number":["DUT25RC(3)033"]}],"id":[{"id":"10.13039\/501100012226","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Small"],"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>\n                    Aptamers, with their high specificity and affinity, are invaluable for diagnostics and therapeutics. However, conventional SELEX (Systematic Evolution of Ligands by Exponential Enrichment) often favors abundant low\u2010affinity sequences, limiting the isolation of rare, high\u2010affinity candidates. To overcome this challenge, we introduce a competitive SELEX strategy that enhances high\u2010affinity aptamer selection by employing a lower\u2010affinity, non\u2010amplifiable aptamer in substantial excess as a competitor. Using\n                    <jats:italic>Clostridioides difficile<\/jats:italic>\n                    (\n                    <jats:italic>C. difficile<\/jats:italic>\n                    ) RNase H2 (CDH2) as the target and ARH1t6 as the competitor, we isolated CDH2\u20101, a high\u2010affinity aptamer with an apparent K\n                    <jats:sub>d<\/jats:sub>\n                    of 0.050 nM\u2014740\u2010fold stronger than ARH1t6. The nearly 100\u2010fold excess of ARH1t6 facilitated the selection of CDH2\u20101, which would typically be outcompeted. CDH2\u20101 enabled paper\u2010based\n                    <jats:italic>C. difficile<\/jats:italic>\n                    detection in fecal samples with a limit of 2.9 \u00d7 10\n                    <jats:sup>3<\/jats:sup>\n                    CFU\/mL, a 120\u2010fold sensitivity improvement over ARH1t6. These findings demonstrate the effectiveness of competitive SELEX in enriching high\u2010affinity aptamers and enhancing biosensor performance.\n                  <\/jats:p>","DOI":"10.1002\/smll.75589","type":"journal-article","created":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T06:44:31Z","timestamp":1788417871000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Competitive SELEX Strategy for High\u2010Affinity Aptamer Isolation and Enhanced Biosensing"],"prefix":"10.1002","author":[{"given":"Jiuxing","family":"Li","sequence":"first","affiliation":[{"name":"School of Environmental Science and Technology Central Hospital of Dalian University of Technology Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) Dalian University of Technology  Dalian Liaoning China"},{"name":"Department of Biochemistry and Biomedical Sciences McMaster University  Hamilton Ontario Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiaxuan","family":"Xiao","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Biomedical Sciences McMaster University  Hamilton Ontario Canada"},{"name":"School of the Environment and Safety Engineering Jiangsu University  Zhenjiang Jiangsu China"},{"name":"College of Chemistry and Chemical Engineering Xi'an Shiyou University  Xi'an Shaanxi China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4313-9523","authenticated-orcid":false,"given":"Jimmy","family":"Gu","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Biomedical Sciences McMaster University  Hamilton Ontario Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4926-347X","authenticated-orcid":false,"given":"Zhen","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of the Environment and Safety Engineering Jiangsu University  Zhenjiang Jiangsu China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7533-6743","authenticated-orcid":false,"given":"Yingfu","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Biomedical Sciences McMaster University  Hamilton Ontario Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,9,2]]},"reference":[{"key":"e_1_2_8_2_1","doi-asserted-by":"publisher","DOI":"10.3390\/life11030193"},{"key":"e_1_2_8_3_1","doi-asserted-by":"publisher","DOI":"10.3389\/fchem.2020.00434"},{"key":"e_1_2_8_4_1","doi-asserted-by":"crossref","DOI":"10.1002\/anie.202318665","article-title":"Development of Better Aptamers: Structured Library Approaches, Selection Methods, and Chemical Modifications","volume":"63","author":"Brown A.","year":"2024","journal-title":"Angewandte Chemie International Edition"},{"key":"e_1_2_8_5_1","doi-asserted-by":"crossref","DOI":"10.1002\/anse.202200012","article-title":"Aptamers for SARS\u2010CoV\u20102: Isolation, Characterization, and Diagnostic and Therapeutic Developments","volume":"2","author":"Amini R.","year":"2022","journal-title":"Analysis and Sensing"},{"key":"e_1_2_8_6_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.trac.2022.116886"},{"key":"e_1_2_8_7_1","doi-asserted-by":"publisher","DOI":"10.1002\/cbic.202000003"},{"key":"e_1_2_8_8_1","doi-asserted-by":"publisher","DOI":"10.1021\/acs.analchem.9b04868"},{"key":"e_1_2_8_9_1","doi-asserted-by":"publisher","DOI":"10.1039\/C9TB02584G"},{"key":"e_1_2_8_10_1","doi-asserted-by":"publisher","DOI":"10.1021\/acs.accounts.1c00355"},{"key":"e_1_2_8_11_1","doi-asserted-by":"publisher","DOI":"10.1021\/jacs.2c09870"},{"key":"e_1_2_8_12_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.202415226"},{"key":"e_1_2_8_13_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.202407049"},{"key":"e_1_2_8_14_1","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa042760"},{"key":"e_1_2_8_15_1","doi-asserted-by":"publisher","DOI":"10.1038\/nrd1955"},{"key":"e_1_2_8_16_1","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.273.32.20556"},{"key":"e_1_2_8_17_1","doi-asserted-by":"crossref","DOI":"10.1016\/j.asems.2024.100125","article-title":"Palladium\u2013Iridium Nanocubes Modified with a High\u2010Affinity DNA Aptamer as Paired Viral Diagnostic and Therapeutic Tools","volume":"4","author":"Liu R.","year":"2024","journal-title":"Advanced Sensor and Energy Materials"},{"key":"e_1_2_8_18_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.202100225"},{"key":"e_1_2_8_19_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.2112942118"},{"key":"e_1_2_8_20_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.202110819"},{"key":"e_1_2_8_21_1","doi-asserted-by":"publisher","DOI":"10.1039\/c3cs60439j"},{"key":"e_1_2_8_22_1","doi-asserted-by":"publisher","DOI":"10.3390\/molecules21121613"},{"key":"e_1_2_8_23_1","doi-asserted-by":"publisher","DOI":"10.1021\/jacs.2c02764"},{"key":"e_1_2_8_24_1","doi-asserted-by":"publisher","DOI":"10.1021\/jacs.2c04835"},{"key":"e_1_2_8_25_1","doi-asserted-by":"publisher","DOI":"10.1021\/jacs.1c08226"},{"key":"e_1_2_8_26_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.nantod.2022.101499"},{"key":"e_1_2_8_27_1","doi-asserted-by":"publisher","DOI":"10.3389\/fcimb.2020.587269"},{"key":"e_1_2_8_28_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.202418725"},{"key":"e_1_2_8_29_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.biomaterials.2013.09.107"},{"key":"e_1_2_8_30_1","first-page":"9587","article-title":"Selection of 2\u2032\u2010deoxy\u20102\u2032\u2010fluoroarabinonucleotide (FANA) Aptamers that Bind HIV\u20101 Reverse Transcriptase With Picomolar Affinity","volume":"43","author":"Ferreira\u2010Bravo I. A.","year":"2015","journal-title":"Nucleic Acids Research"},{"key":"e_1_2_8_31_1","doi-asserted-by":"publisher","DOI":"10.1093\/nar\/gks899"},{"key":"e_1_2_8_32_1","doi-asserted-by":"publisher","DOI":"10.1093\/nar\/gkab574"},{"key":"e_1_2_8_33_1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.182095699"},{"key":"e_1_2_8_34_1","doi-asserted-by":"publisher","DOI":"10.1021\/ja103023m"},{"key":"e_1_2_8_35_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41598\u2010019\u201043187\u20106"},{"key":"e_1_2_8_36_1","doi-asserted-by":"publisher","DOI":"10.1021\/ac300330g"},{"key":"e_1_2_8_37_1","doi-asserted-by":"publisher","DOI":"10.1021\/acs.analchem.0c01394"},{"key":"e_1_2_8_38_1","doi-asserted-by":"publisher","DOI":"10.1021\/acsami.0c20277"},{"key":"e_1_2_8_39_1","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa1910215"},{"key":"e_1_2_8_40_1","unstructured":"Centers for Disease Control and Prevention. Clostridioides difficile Infection (CDI) Surveillance 2026 https:\/\/www.cdc.gov\/hai\/eip\/cdiff\u2010tracking.html."},{"key":"e_1_2_8_41_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.202000025"},{"key":"e_1_2_8_42_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.201901192"},{"key":"e_1_2_8_43_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.biochi.2017.08.015"},{"key":"e_1_2_8_44_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.201100477"},{"key":"e_1_2_8_45_1","doi-asserted-by":"publisher","DOI":"10.1128\/JCM.41.2.730\u2010734.2003"}],"container-title":["Small"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/smll.75589","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/smll.75589","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/smll.75589","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T06:44:33Z","timestamp":1788417873000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/smll.75589"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,2]]},"references-count":44,"alternative-id":["10.1002\/smll.75589"],"URL":"https:\/\/doi.org\/10.1002\/smll.75589","archive":["Portico"],"relation":{},"ISSN":["1613-6810","1613-6829"],"issn-type":[{"value":"1613-6810","type":"print"},{"value":"1613-6829","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,2]]},"assertion":[{"value":"2026-08-07","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-08-26","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-09-02","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e75589"}}