{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T16:00:57Z","timestamp":1767888057882,"version":"3.49.0"},"reference-count":17,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2012,9,10]],"date-time":"2012-09-10T00:00:00Z","timestamp":1347235200000},"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>Changes in mass loading on the surface of acoustic biosensors result in output frequency shifts which provide precise measurements of analytes. Therefore, to detect a particular biomarker, the sensor delay path must be judiciously designed to maximize sensitivity and specificity. B-cell lymphoma 2 protein (Bcl-2) found in urine is under investigation as a biomarker for non-invasive early detection of ovarian cancer. In this study, surface chemistry and biofunctionalization approaches were evaluated for their effectiveness in presenting antibodies for Bcl-2 capture while minimizing non-specific protein adsorption. The optimal combination of sequentially adsorbing protein A\/G, anti-Bcl-2 IgG and Pluronic F127 onto a hydrophobic surface provided the greatest signal-to-noise ratio and enabled the reliable detection of Bcl-2 concentrations below that previously identified for early stage ovarian cancer as characterized by a modified ELISA method. Finally, the optimal surface modification was applied to a prototype acoustic device and the frequency shift for a range of Bcl-2 concentration was quantified to demonstrate the effectiveness in surface acoustic wave (SAW)-based detection applications. The surface functionalization approaches demonstrated here to specifically and sensitively detect Bcl-2 in a working ultrasonic MEMS biosensor prototype can easily be modified to detect additional biomarkers and enhance other acoustic biosensors.<\/jats:p>","DOI":"10.3390\/s120912317","type":"journal-article","created":{"date-parts":[[2012,9,10]],"date-time":"2012-09-10T12:48:57Z","timestamp":1347281337000},"page":"12317-12328","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Surface Modification on Acoustic Wave Biosensors for Enhanced Specificity"],"prefix":"10.3390","volume":"12","author":[{"given":"Onursal","family":"Onen","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, University of South Florida, 4202 E Fowler Ave, ENB 118, Tampa, FL 33620, USA"}]},{"given":"Asad A.","family":"Ahmad","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of South Florida, 4202 E Fowler Ave, ENB 118, Tampa, FL 33620, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4368-2238","authenticated-orcid":false,"given":"Rasim","family":"Guldiken","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of South Florida, 4202 E Fowler Ave, ENB 118, Tampa, FL 33620, USA"}]},{"given":"Nathan D.","family":"Gallant","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of South Florida, 4202 E Fowler Ave, ENB 118, Tampa, FL 33620, USA"}]}],"member":"1968","published-online":{"date-parts":[[2012,9,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ballantine, D.S., White, R.M., Martin, S.J., Ricco, A.J., Zellers, E.T., Frye, G.C., and Wohltjen, H. 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