{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,4]],"date-time":"2025-11-04T16:11:14Z","timestamp":1762272674168,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,1,29]],"date-time":"2021-01-29T00:00:00Z","timestamp":1611878400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003407","name":"Ministero dell\u2019Istruzione, dell\u2019Universit\u00e0 e della Ricerca","doi-asserted-by":"publisher","award":["2015FFY97L","2017Y2PAB8"],"award-info":[{"award-number":["2015FFY97L","2017Y2PAB8"]}],"id":[{"id":"10.13039\/501100003407","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000830","name":"North Atlantic Treaty Organization","doi-asserted-by":"publisher","award":["985042"],"award-info":[{"award-number":["985042"]}],"id":[{"id":"10.13039\/501100000830","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100014439","name":"Partnership for Research and Innovation in the Mediterranean Area","doi-asserted-by":"publisher","award":["FEDKITO"],"award-info":[{"award-number":["FEDKITO"]}],"id":[{"id":"10.13039\/100014439","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In recent years, there has been an increasing demand for predictive and sensitive in vitro tools for drug discovery. Split complementation assays have the potential to enlarge the arsenal of in vitro tools for compound screening, with most of them relying on well-established reporter gene assays. In particular, ligand-induced complementation of split luciferases is emerging as a suitable approach for monitoring protein\u2013protein interactions. We hereby report an intracellular nanosensor for the screening of compounds with androgenic activity based on a split NanoLuc reporter. We also confirm the suitability of using 3D spheroids of Human Embryonic Kidney (HEK-293) cells for upgrading the 2D cell-based assay. A limit of detection of 4 pM and a half maximal effective concentration (EC50) of 1.7 \u00b1 0.3 nM were obtained for testosterone with HEK293 spheroids. This genetically encoded nanosensor also represents a new tool for real time imaging of the activation state of the androgen receptor, thus being suitable for analysing molecules with androgenic activity, including new drugs or endocrine disrupting molecules.<\/jats:p>","DOI":"10.3390\/s21030893","type":"journal-article","created":{"date-parts":[[2021,1,29]],"date-time":"2021-01-29T02:58:21Z","timestamp":1611889101000},"page":"893","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["A Genetically Encoded Bioluminescence Intracellular Nanosensor for Androgen Receptor Activation Monitoring in 3D Cell Models"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5673-3073","authenticated-orcid":false,"given":"Maria Maddalena","family":"Calabretta","sequence":"first","affiliation":[{"name":"Department of Chemistry \u201cGiacomo Ciamician\u201d, University of Bologna, 40126 Bologna, Italy"},{"name":"Center for Applied Biomedical Research (CRBA), University of Bologna, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonia","family":"Lopreside","sequence":"additional","affiliation":[{"name":"Department of Chemistry \u201cGiacomo Ciamician\u201d, University of Bologna, 40126 Bologna, Italy"},{"name":"Center for Applied Biomedical Research (CRBA), University of Bologna, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laura","family":"Montali","sequence":"additional","affiliation":[{"name":"Department of Chemistry \u201cGiacomo Ciamician\u201d, University of Bologna, 40126 Bologna, Italy"},{"name":"Center for Applied Biomedical Research (CRBA), University of Bologna, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Luca","family":"Cevenini","sequence":"additional","affiliation":[{"name":"Department of Chemistry \u201cGiacomo Ciamician\u201d, University of Bologna, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aldo","family":"Roda","sequence":"additional","affiliation":[{"name":"Department of Chemistry \u201cGiacomo Ciamician\u201d, University of Bologna, 40126 Bologna, Italy"},{"name":"Istituto Nazionale di Biostrutture e Biosistemi (INBB), 00136 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8651-0575","authenticated-orcid":false,"given":"Elisa","family":"Michelini","sequence":"additional","affiliation":[{"name":"Department of Chemistry \u201cGiacomo Ciamician\u201d, University of Bologna, 40126 Bologna, Italy"},{"name":"Center for Applied Biomedical Research (CRBA), University of Bologna, 40126 Bologna, Italy"},{"name":"Istituto Nazionale di Biostrutture e Biosistemi (INBB), 00136 Rome, Italy"},{"name":"Health Sciences and Technologies-Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Ozzano dell\u2019Emilia, 40064 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2552","DOI":"10.1021\/ac100104q","article-title":"Rapid and high-sensitivity cell-based assays of protein-protein interactions using split click beetle luciferase complementation: An approach to the study of G-protein-coupled receptors","volume":"82","author":"Misawa","year":"2010","journal-title":"Anal. 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