{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T14:57:37Z","timestamp":1774364257483,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2013,8,5]],"date-time":"2013-08-05T00:00:00Z","timestamp":1375660800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Chili hotness is very much dependent on the concentration of capsaicin present in the chili fruit. A new biosensor based on a horseradish peroxidase enzyme-capsaicin reaction mediated by ferrocene has been successfully developed for the amperometric determination of chili hotness. The amperometric biosensor is fabricated based on a  single-step immobilization of both ferrocene and horseradish peroxidase in a photocurable hydrogel membrane, poly(2-hydroxyethyl methacrylate). With mediation by ferrocene, the biosensor could measure capsaicin concentrations at a potential 0.22 V (vs. Ag\/AgCl), which prevented potential interference from other electroactive species in the sample. Thus a good selectivity towards capsaicin was demonstrated. The linear response range of the biosensor towards capsaicin was from 2.5\u201399.0 \u00b5M with detection limit of 1.94 \u00b5M. A good relative standard deviation (RSD) for reproducibility of 6.4%\u20139.9% was obtained. The capsaicin biosensor demonstrated long-term stability for up to seven months. The performance of the biosensor has been validated using a standard method for the analysis of capsaicin based on HPLC.<\/jats:p>","DOI":"10.3390\/s130810014","type":"journal-article","created":{"date-parts":[[2013,8,5]],"date-time":"2013-08-05T12:16:02Z","timestamp":1375704962000},"page":"10014-10026","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":33,"title":["An Amperometric Biosensor Utilizing a Ferrocene-Mediated Horseradish Peroxidase Reaction for the Determination of Capsaicin (Chili Hotness)"],"prefix":"10.3390","volume":"13","author":[{"given":"Rosmawani","family":"Mohammad","sequence":"first","affiliation":[{"name":"School of Chemical Sciences and Food Technology, Faculty of Science and Technology,  Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Musa","family":"Ahmad","sequence":"additional","affiliation":[{"name":"School of Chemical Sciences and Food Technology, Faculty of Science and Technology,  Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lee","family":"Heng","sequence":"additional","affiliation":[{"name":"School of Chemical Sciences and Food Technology, Faculty of Science and Technology,  Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2013,8,5]]},"reference":[{"key":"ref_1","unstructured":"Li, T.S.C. 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