{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T07:58:24Z","timestamp":1778745504336,"version":"3.51.4"},"reference-count":28,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2016,12,2]],"date-time":"2016-12-02T00:00:00Z","timestamp":1480636800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The present article introduces a new approach to fabricate carbon paste sensors, including carbon paste, modified carbon paste inclusion \u03b2-cyclodextrin, and carbon nanotubes for the quantification of dorzolamide hydrochloride (DRZ). This study is mainly based on the construction of three different carbon paste sensors by the incorporation of DRZ with phosphotungstic acid (PTA) to form dorzolamide-phosphotungstate (DRZ-PT) as an electroactive material in the presence of the solvent mediator ortho-nitrophenyloctyl ether (o-NPOE). The fabricated conventional carbon paste sensor (sensor I), as well as the other modified carbon paste sensors using \u03b2-cyclodextrin (sensor II) and carbon nanotubes (sensor III), have been investigated. The sensors displayed Nernstian responses of 55.4 \u00b1 0.6, 56.4 \u00b1 0.4 and 58.1 \u00b1 0.2 mV\u00b7decade\u22121 over concentration ranges of 1.0 \u00d7 10\u22125\u20131.0 \u00d7 10\u22122, 1.0 \u00d7 10\u22126\u20131.0 \u00d7 10\u22122, and 5.0 \u00d7 10\u22128\u20131.0 \u00d7 10\u22122 mol\u00b7L\u22121 with lower detection limits of 5.0 \u00d7 10\u22126, 5.0 \u00d7 10\u22127, and 2.5 \u00d7 10\u22129 mol\u00b7L\u22121 for sensors I, II, and III, respectively. The critical performance of the developed sensors was checked with respect to the effect of various parameters, including pH, selectivity, response time, linear concentration relationship, lifespan, etc. Method validation was applied according to the international conference on harmonisation of technical requirements for registration of pharmaceuticals for human use ICH guidelines. The developed sensors were employed for the determination of DRZ in its bulk and dosage forms, as well as bio-samples. The observed data were statistically analyzed and compared with those obtained from other published methods.<\/jats:p>","DOI":"10.3390\/ijms17122027","type":"journal-article","created":{"date-parts":[[2016,12,2]],"date-time":"2016-12-02T10:36:37Z","timestamp":1480674997000},"page":"2027","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["New Electrochemically-Modified Carbon Paste Inclusion \u03b2-Cyclodextrin and Carbon Nanotubes Sensors for Quantification of Dorzolamide Hydrochloride"],"prefix":"10.3390","volume":"17","author":[{"given":"Nawal","family":"Alarfaj","sequence":"first","affiliation":[{"name":"Department of Chemistry, College of Science, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9793-7761","authenticated-orcid":false,"given":"Maha","family":"El-Tohamy","sequence":"additional","affiliation":[{"name":"Department of Chemistry, College of Science, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia"},{"name":"General Administration and Medical Affairs, Zagazig University, Zagazig 44519, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,12,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"15","DOI":"10.3109\/10799899909036635","article-title":"Chance favors the prepared mind from serendipity to rational drug design","volume":"19","author":"Kubinyi","year":"1999","journal-title":"J. Recept. Signal Transduct. 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