{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T20:52:37Z","timestamp":1773953557908,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,1,5]],"date-time":"2020-01-05T00:00:00Z","timestamp":1578182400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A new methodology involving the use of Bovine Serum Albumin (BSA) as a probe and liquid crystal (LC) as a signal reporter for the detection of heavy metal ions in water at neutral pH was developed. BSA acted as a multi-dentate ligand for the detection of multiple metal ions. The LC sensor was fabricated by immobilizing 3 \u00b5g mL\u22121 BSA solution on dimethyloctadecyl-[3-(trimethoxysilyl)propyl]ammonium chloride (DMOAP)-coated glass slides. In the absence of heavy metal ions, a dark optical image was observed, while in their presence, a dark optical image turned to bright. The optical response was characterized by using a polarized optical microscope (POM). The BSA based LC sensor selectively detected toxic metal ions as compared to s block metal ions and ammonium ions in water. Moreover, the limit of detection was found to be very low (i.e., 1 nM) for the developed new biosensor in comparison to reported biosensors.<\/jats:p>","DOI":"10.3390\/s20010298","type":"journal-article","created":{"date-parts":[[2020,1,6]],"date-time":"2020-01-06T03:48:48Z","timestamp":1578282528000},"page":"298","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":44,"title":["Bovine Serum Albumin Protein-Based Liquid Crystal Biosensors for Optical Detection of Toxic Heavy Metals in Water"],"prefix":"10.3390","volume":"20","author":[{"given":"Noor ul","family":"Amin","sequence":"first","affiliation":[{"name":"Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan"},{"name":"Department of Chemical &amp; Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Humaira Masood","family":"Siddiqi","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yang","family":"Kun Lin","sequence":"additional","affiliation":[{"name":"Department of Chemical &amp; Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4850-362X","authenticated-orcid":false,"given":"Zakir","family":"Hussain","sequence":"additional","affiliation":[{"name":"School of Chemical and Materials Engineering (SCME), National University of Sciences and Technology (NUST), H-12, Islamabad 44000, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nasir","family":"Majeed","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1007\/978-3-7643-8340-4_6","article-title":"Heavy Metal Toxicity and the Environment","volume":"Volume 101","author":"Luch","year":"2012","journal-title":"Molecular, Clinical and Environmental Toxicology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"953","DOI":"10.1046\/j.1365-2672.2003.01870.x","article-title":"Metal ion enhancement of fungal growth, gene expression and aflatoxin synthesis in Aspergillus flavus: RT-PCR characterization","volume":"94","author":"Cuero","year":"2003","journal-title":"J. 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