{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,11]],"date-time":"2026-07-11T00:29:45Z","timestamp":1783729785815,"version":"3.55.0"},"reference-count":21,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2011,3,28]],"date-time":"2011-03-28T00:00:00Z","timestamp":1301270400000},"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>This paper presents a fast, highly sensitive and low-cost tapered optical fiber biosensor that enables the label-free detection of biomolecules. The sensor takes advantage of the interference effect between the fiber\u2019s first two propagation modes along the taper waist region. The biomolecules bonded on the taper surface were determined by demodulating the transmission spectrum phase shift. Because of the sharp spectrum fringe signals, as well as a relatively long biomolecule testing region, the sensor displayed a fast response and was highly sensitive. To better understand the influence of various biomolecules on the sensor, a numerical simulation that varied biolayer parameters such as thickness and refractive index was performed. The results showed that the spectrum fringe shift was obvious to be measured even when the biolayer was only nanometers thick. A microchannel chip was designed and fabricated for the protection of the sensor and biotesting. Microelectromechanical systems (MEMS) fabrication techniques were used to precisely control the profile and depth of the microchannel on the silicon chip with an accuracy of 2 \u03bcm. A tapered optical fiber biosensor was fabricated and evaluated with an Immune globulin G (IgG) antibody-antigen pair.<\/jats:p>","DOI":"10.3390\/s110403780","type":"journal-article","created":{"date-parts":[[2011,3,28]],"date-time":"2011-03-28T10:46:42Z","timestamp":1301309202000},"page":"3780-3790","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":163,"title":["Tapered Optical Fiber Sensor for Label-Free Detection of Biomolecules"],"prefix":"10.3390","volume":"11","author":[{"given":"Ye","family":"Tian","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenhui","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nan","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaotian","family":"Zou","sequence":"additional","affiliation":[{"name":"Biomedical Engineering and Biotechnology Doctoral Program, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xingwei","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"},{"name":"Biomedical Engineering and Biotechnology Doctoral Program, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2011,3,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"355","DOI":"10.1016\/j.snb.2005.12.033","article-title":"Infrared biosensors using hydrophobic chalcogenide fibers sensitized with live cells","volume":"119","author":"Lucas","year":"2006","journal-title":"Sens. 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