{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,1]],"date-time":"2026-02-01T04:09:08Z","timestamp":1769918948998,"version":"3.49.0"},"reference-count":40,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,4,12]],"date-time":"2021-04-12T00:00:00Z","timestamp":1618185600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100015622","name":"Ministerul Cercet\u0103rii \u015fi Inov\u0103rii","doi-asserted-by":"publisher","award":["Operational Programme Competitiveness 2014-2020, Project: NANOBIOSURF-SMIS 103528"],"award-info":[{"award-number":["Operational Programme Competitiveness 2014-2020, Project: NANOBIOSURF-SMIS 103528"]}],"id":[{"id":"10.13039\/501100015622","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100015622","name":"Ministerul Cercet\u0103rii \u015fi Inov\u0103rii","doi-asserted-by":"publisher","award":["Core Program PN19-030101 (contract no.21\/2019)"],"award-info":[{"award-number":["Core Program PN19-030101 (contract no.21\/2019)"]}],"id":[{"id":"10.13039\/501100015622","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A dual strategy for the electrochemical detection for 20S proteasome (20S) is proposed, based on the oriented immobilization of a capture monoclonal antibody (Ab\u03b2) on a self-assembled monolayer of 4-mercaptophenylboronic acid (4-MPBA) on gold electrodes, which led to the Au\/4-MPBA\/Ab\u03b2 immunosensor. The methodology comprises the correlation of 20S concentration with (i) its proteolytic activity toward the Z-LLE-AMC substrate, using the Au\/4-MPBA\/Ab\u03b2\/20S, and (ii) the enzymatic activity of an alkaline phosphatase (AlkP) from the AlkP-labeled secondary antibody (Abcore-AlkP), which involves the conversion of aminophenylphosphate to the electroactive aminophenol using Au\/4-MPBA\/Ab\u03b2\/20S\/Abcore-AlkP. The step-by-step construction of the immunosensor and the interactions at its surface were evaluated by surface plasmon resonance and gravimetric analysis with quartz crystal microbalance, showing a high affinity between both antibodies and 20S. Morphological analysis by scanning electron microscopy demonstrated a pattern of parallel lines upon immobilization of Ab\u03b2 on 4-MPBA and morphological changes to a well-organized granular structure upon binding of 20S. A voltametric and impedimetric characterization was performed after each step in the immunosensor construction. The two detection strategies were evaluated. It was shown that the immunosensor responds linearly with 20S concentration in the range between 5 and 100 \u00b5g mL\u22121, which corresponds to proteasome levels in serum in the case of diverse pathological situations, and LoD values of 1.4 and 0.2 \u00b5g mL\u22121 were calculated for the detection strategies. The immunosensor was applied to the detection of 20S in serum samples with recovery values ranging from 101 to 103%.<\/jats:p>","DOI":"10.3390\/s21082702","type":"journal-article","created":{"date-parts":[[2021,4,12]],"date-time":"2021-04-12T11:05:06Z","timestamp":1618225506000},"page":"2702","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Immobilized Antibodies on Mercaptophenylboronic Acid Monolayers for Dual-Strategy Detection of 20S Proteasome"],"prefix":"10.3390","volume":"21","author":[{"given":"Madalina M.","family":"Barsan","sequence":"first","affiliation":[{"name":"National Institute of Materials Physics, Atomistilor 405A, 077125 M\u0103gurele, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2829-7163","authenticated-orcid":false,"given":"Caroline G.","family":"Sanz","sequence":"additional","affiliation":[{"name":"National Institute of Materials Physics, Atomistilor 405A, 077125 M\u0103gurele, Romania"}]},{"given":"Melania","family":"Onea","sequence":"additional","affiliation":[{"name":"National Institute of Materials Physics, Atomistilor 405A, 077125 M\u0103gurele, Romania"},{"name":"Faculty of Physics, University of Bucharest, Atomistilor 405, 077125 M\u0103gurele, Romania"}]},{"given":"Victor C.","family":"Diculescu","sequence":"additional","affiliation":[{"name":"National Institute of Materials Physics, Atomistilor 405A, 077125 M\u0103gurele, Romania"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4955","DOI":"10.1158\/0008-5472.CAN-14-1211","article-title":"Emerging Potential of Therapeutic Targeting of Ubiquitin-Specific Proteases in the Treatment of Cancer","volume":"74","author":"Pal","year":"2014","journal-title":"Cancer Res."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"417","DOI":"10.1038\/nrclinonc.2016.206","article-title":"Proteasome inhibitors in cancer therapy","volume":"14","author":"Manasanch","year":"2017","journal-title":"Nat. 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