{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T10:54:07Z","timestamp":1785840847014,"version":"3.56.0"},"reference-count":41,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T00:00:00Z","timestamp":1785801600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Union Horizon Europe program","doi-asserted-by":"publisher","award":["GA101057524"],"award-info":[{"award-number":["GA101057524"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The growing demand for wearable and Internet of Medical Things (IoMT) devices is driving the development of compact, low-power platforms for continuous physiological monitoring. Bioimpedance analysis represents a versatile non-invasive technique for the assessment of tissue properties, body composition, and respiratory dynamics. This work presents a comprehensive experimental validation of a compact bioimpedance measurement platform based on the SENSIPLUS chip, a CMOS sensor interface integrating a frequency-programmable lock-in amplifier for Electrochemical Impedance Spectroscopy in the 10 kHz\u20131 MHz range. The platform was validated at three complementary levels: (i) electrical characterization on Debye tissue-equivalent circuits using a three-point bilinear calibration, with analysis of the electrode\u2013skin contribution and repeatability assessment; (ii) in vivo multi-frequency bioimpedance spectroscopy (BIS) with Cole\u2013Cole model fitting and hook-effect correction; and (iii) single-frequency thoracic impedance plethysmography for respiratory monitoring. Results were compared against an Agilent E4980A precision Inductance (L), Capacitance (C), and Resistance (R) meter and a calibrated spirometer. The presented device achieved a maximum resistance error below 5.7% and reactance deviation under 6 \u03a9 across the investigated frequency range, Cole\u2013Cole parameters consistent with reference values, and strong linear correlation (R2=0.97) between thoracic impedance variations and tidal volume, with respiratory rate estimation errors below 2% across the ten sessions, specifically 1.43% during normal breathing and 1.96% during deep breathing. These results demonstrate that the SENSIPLUS-based platform achieves metrological performance compatible with the requirements of wearable IoMT applications, here demonstrated in a single-subject proof-of-concept study, while relying for all critical analog functions on a compact (1.5\u00d71.5) mm2 system-on-chip with low power consumption (1.5 mW).<\/jats:p>","DOI":"10.3390\/s26154922","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T10:38:08Z","timestamp":1785839888000},"page":"4922","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Experimental Validation of a Compact and Versatile Bioimpedance Measurement Platform Based on the SENSIPLUS Chip"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-4567-7192","authenticated-orcid":false,"given":"Lorenzo","family":"Giannini","sequence":"first","affiliation":[{"name":"Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, 00184 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2898-9047","authenticated-orcid":false,"given":"Rita","family":"Asquini","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, 00184 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8071-5406","authenticated-orcid":false,"given":"Alessio","family":"Buzzin","sequence":"additional","affiliation":[{"name":"Interdisciplinary Department of Wellbeing, Health and Environmental Sustainability, Sapienza University of Rome, 02100 Rieti, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simone","family":"Contardi","sequence":"additional","affiliation":[{"name":"Sensichips s.r.l., 04011 Aprilia, Italy"},{"name":"Department of Information Engineering, University of Pisa, 56100 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2073-1073","authenticated-orcid":false,"given":"Paolo","family":"Bruschi","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, University of Pisa, 56100 Pisa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3822-139X","authenticated-orcid":false,"given":"Emanuele","family":"Piuzzi","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, 00184 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"495","DOI":"10.1093\/comjnl\/47.4.495","article-title":"Medical monitoring applications for wearable computing","volume":"47","author":"Raskovic","year":"2004","journal-title":"Comput. 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