{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T06:13:10Z","timestamp":1776406390071,"version":"3.51.2"},"reference-count":51,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2020,2,26]],"date-time":"2020-02-26T00:00:00Z","timestamp":1582675200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004515","name":"Universiti Kebangsaan Malaysia","doi-asserted-by":"publisher","award":["MI-2019-016"],"award-info":[{"award-number":["MI-2019-016"]}],"id":[{"id":"10.13039\/501100004515","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A novel label-free electrochemical DNA biosensor was constructed for the determination of Escherichia coli bacteria in environmental water samples. The aminated DNA probe was immobilized onto hollow silica microspheres (HSMs) functionalized with 3-aminopropyltriethoxysilane and deposited onto a screen-printed electrode (SPE) carbon paste with supported gold nanoparticles (AuNPs). The biosensor was optimized for higher specificity and sensitivity. The label-free E. coli DNA biosensor exhibited a dynamic linear response range of 1 \u00d7 10\u221210 \u00b5M to 1 \u00d7 10\u22125 \u00b5M (R2 = 0.982), with a limit of detection at 1.95 \u00d7 10\u221215 \u00b5M, without a redox mediator. The sensitivity of the developed DNA biosensor was comparable to the non-complementary and single-base mismatched DNA. The DNA biosensor demonstrated a stable response up to 21 days of storage at 4 \u2103 and pH 7. The DNA biosensor response was regenerable over three successive regeneration and rehybridization cycles.<\/jats:p>","DOI":"10.3390\/s20051279","type":"journal-article","created":{"date-parts":[[2020,2,27]],"date-time":"2020-02-27T03:21:16Z","timestamp":1582773676000},"page":"1279","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["A Highly Sensitive Impedimetric DNA Biosensor Based on Hollow Silica Microspheres for Label-Free Determination of E. coli"],"prefix":"10.3390","volume":"20","author":[{"given":"Eda","family":"Yuhana Ariffin","sequence":"first","affiliation":[{"name":"Department of Chemical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lee Yook","family":"Heng","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ling Ling","family":"Tan","sequence":"additional","affiliation":[{"name":"Southeast Asia Disaster Prevention Research Initiative (SEADPRI-UKM), Institute for Environment and Development (LESTARI), Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nurul Huda","family":"Abd Karim","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Siti Aishah","family":"Hasbullah","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,2,26]]},"reference":[{"key":"ref_1","unstructured":"(2019, December 27). 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