{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T02:12:02Z","timestamp":1769825522864,"version":"3.49.0"},"reference-count":37,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,21]],"date-time":"2022-12-21T00:00:00Z","timestamp":1671580800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key Research and Development Project","award":["2021YFA1201602"],"award-info":[{"award-number":["2021YFA1201602"]}]},{"name":"National Key Research and Development Project","award":["cstc2020jcyj-cxttX0005"],"award-info":[{"award-number":["cstc2020jcyj-cxttX0005"]}]},{"name":"National Key Research and Development Project","award":["cstc2022ycjh-bgzxm0206"],"award-info":[{"award-number":["cstc2022ycjh-bgzxm0206"]}]},{"name":"National Key Research and Development Project","award":["2018CDQYGD0020"],"award-info":[{"award-number":["2018CDQYGD0020"]}]},{"name":"National Key Research and Development Project","award":["cqu2018CDHB1A05"],"award-info":[{"award-number":["cqu2018CDHB1A05"]}]},{"name":"Natural Science Foundation of Innovative Research Groups","award":["2021YFA1201602"],"award-info":[{"award-number":["2021YFA1201602"]}]},{"name":"Natural Science Foundation of Innovative Research Groups","award":["cstc2020jcyj-cxttX0005"],"award-info":[{"award-number":["cstc2020jcyj-cxttX0005"]}]},{"name":"Natural Science Foundation of Innovative Research Groups","award":["cstc2022ycjh-bgzxm0206"],"award-info":[{"award-number":["cstc2022ycjh-bgzxm0206"]}]},{"name":"Natural Science Foundation of Innovative Research Groups","award":["2018CDQYGD0020"],"award-info":[{"award-number":["2018CDQYGD0020"]}]},{"name":"Natural Science Foundation of Innovative Research Groups","award":["cqu2018CDHB1A05"],"award-info":[{"award-number":["cqu2018CDHB1A05"]}]},{"name":"Natural Science Foundation Projects of Chongqing","award":["2021YFA1201602"],"award-info":[{"award-number":["2021YFA1201602"]}]},{"name":"Natural Science Foundation Projects of Chongqing","award":["cstc2020jcyj-cxttX0005"],"award-info":[{"award-number":["cstc2020jcyj-cxttX0005"]}]},{"name":"Natural Science Foundation Projects of Chongqing","award":["cstc2022ycjh-bgzxm0206"],"award-info":[{"award-number":["cstc2022ycjh-bgzxm0206"]}]},{"name":"Natural Science Foundation Projects of Chongqing","award":["2018CDQYGD0020"],"award-info":[{"award-number":["2018CDQYGD0020"]}]},{"name":"Natural Science Foundation Projects of Chongqing","award":["cqu2018CDHB1A05"],"award-info":[{"award-number":["cqu2018CDHB1A05"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["2021YFA1201602"],"award-info":[{"award-number":["2021YFA1201602"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["cstc2020jcyj-cxttX0005"],"award-info":[{"award-number":["cstc2020jcyj-cxttX0005"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["cstc2022ycjh-bgzxm0206"],"award-info":[{"award-number":["cstc2022ycjh-bgzxm0206"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["2018CDQYGD0020"],"award-info":[{"award-number":["2018CDQYGD0020"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["cqu2018CDHB1A05"],"award-info":[{"award-number":["cqu2018CDHB1A05"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Flexible pressure sensors with the capability of monitoring human vital signs show broad application prospects in personalized healthcare. In this work, a hair-based flexible pressure sensor (HBPS) consisting of lost hair and polymer films was proposed for the continuous monitoring of the human epidermal arterial pulse waveform. A macroscale mesh structure formed by lost hair provides a simplified spacer that endows the triboelectric-based flexible pressure sensor with sufficient contact\u2013separation space. Based on this mesh structure design, the hair-based flexible pressure sensor can respond to the slight pressure change caused by an object with 5 mg weight and hold a stable output voltage under 1\u201330 Hz external pressure excitation. Additionally, the hair-based flexible pressure sensor showed great sensitivity (0.9 V\/kPa) and decent stability after 4500 cycles of operation. Given these compelling features, the HBPS can successfully measure the human epidermal arterial pulses with obvious details at different arteries. The proposed HBPS can also be used to monitor the pulse signals of different subjects. Furthermore, the three different pulse wave transmission time (PTT) values (PTT-foot, PTT-middle, and PTT-peak) can be obtained by simultaneously monitoring human pulse and electrocardiogram signals, which has enormous application potential for assessing cardiovascular system health.<\/jats:p>","DOI":"10.3390\/s23010045","type":"journal-article","created":{"date-parts":[[2022,12,21]],"date-time":"2022-12-21T06:11:24Z","timestamp":1671603084000},"page":"45","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["A Flexible Pressure Sensor with a Mesh Structure Formed by Lost Hair for Human Epidermal Pulse Wave Monitoring"],"prefix":"10.3390","volume":"23","author":[{"given":"Xue","family":"Wang","sequence":"first","affiliation":[{"name":"Department of Optoelectronic Engineering, Key Laboratory of Optoelectronic Technology and Systems Ministry of Education, Chongqing University, Chongqing 400044, China"},{"name":"Department of Optoelectronic Engineering, Chongqing Key Laboratory of Laser Control & Precision Measurement, Chongqing University, Chongqing 400044, China"}]},{"given":"Zhiping","family":"Feng","sequence":"additional","affiliation":[{"name":"Department of Optoelectronic Engineering, Key Laboratory of Optoelectronic Technology and Systems Ministry of Education, Chongqing University, Chongqing 400044, China"},{"name":"Department of Optoelectronic Engineering, Chongqing Key Laboratory of Laser Control & Precision Measurement, Chongqing University, Chongqing 400044, China"}]},{"given":"Peng","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Optoelectronic Engineering, Key Laboratory of Optoelectronic Technology and Systems Ministry of Education, Chongqing University, Chongqing 400044, China"},{"name":"Department of Optoelectronic Engineering, Chongqing Key Laboratory of Laser Control & Precision Measurement, Chongqing University, Chongqing 400044, China"}]},{"given":"Luna","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Optoelectronic Engineering, Key Laboratory of Optoelectronic Technology and Systems Ministry of Education, Chongqing University, Chongqing 400044, China"},{"name":"Department of Optoelectronic Engineering, Chongqing Key Laboratory of Laser Control & Precision Measurement, Chongqing University, Chongqing 400044, China"}]},{"given":"Liang","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Optoelectronic Engineering, Key Laboratory of Optoelectronic Technology and Systems Ministry of Education, Chongqing University, Chongqing 400044, China"},{"name":"Department of Optoelectronic Engineering, Chongqing Key Laboratory of Laser Control & Precision Measurement, Chongqing University, Chongqing 400044, China"}]},{"given":"Yufen","family":"Wu","sequence":"additional","affiliation":[{"name":"College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 401331, China"}]},{"given":"Jin","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Optoelectronic Engineering, Key Laboratory of Optoelectronic Technology and Systems Ministry of Education, Chongqing University, Chongqing 400044, China"},{"name":"Department of Optoelectronic Engineering, Chongqing Key Laboratory of Laser Control & Precision Measurement, Chongqing University, Chongqing 400044, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"23402","DOI":"10.3390\/s150923402","article-title":"Wearable Sensing of In-Ear Pressure for Heart Rate Monitoring with a Piezoelectric Sensor","volume":"15","author":"Park","year":"2015","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1016\/j.pcad.2019.11.002","article-title":"Systemic hemodynamic atherothrombotic syndrome (SHATS)\u2014Coupling vascular disease and blood pressure variability: Proposed concept from pulse of Asia","volume":"63","author":"Kario","year":"2020","journal-title":"Prog. Cardiovasc. Dis."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1681","DOI":"10.1021\/acssensors.0c02324","article-title":"Comprehensive Review on Triboelectric Nanogenerator Based Wrist Pulse Measurement: Sensor Fabrication and Diagnosis of Arterial Pressure","volume":"6","author":"Venugopal","year":"2021","journal-title":"ACS Sens."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1053","DOI":"10.1007\/s11265-018-1428-x","article-title":"Multimodal Cardiovascular Information Monitor Using Piezoelectric Transducers for Wearable Healthcare","volume":"91","author":"Okano","year":"2018","journal-title":"J. Signal Process. Syst."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Roh, D., Han, S., Park, J., and Shin, H. (2019). Development of a Multi-Array Pressure Sensor Module for Radial Artery Pulse Wave Measurement. Sensors, 20.","DOI":"10.3390\/s20010033"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2102378","DOI":"10.1002\/adfm.202102378","article-title":"Enabling the Unconstrained Epidermal Pulse Wave Monitoring via Finger-Touching","volume":"31","author":"Wang","year":"2021","journal-title":"Adv. Funct. Mater."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"687","DOI":"10.1038\/s41551-018-0287-x","article-title":"Monitoring of the central blood pressure waveform via a conformal ultrasonic device","volume":"2","author":"Wang","year":"2018","journal-title":"Nat. Biomed. Eng."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"737","DOI":"10.1038\/s41551-021-00685-1","article-title":"An epidermal patch for the simultaneous monitoring of haemodynamic and metabolic biomarkers","volume":"5","author":"Sempionatto","year":"2021","journal-title":"Nat. Biomed. Eng."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1604373","DOI":"10.1002\/adfm.201604373","article-title":"Miniaturized Battery-Free Wireless Systems for Wearable Pulse Oximetry","volume":"27","author":"Kim","year":"2017","journal-title":"Adv. Funct. Mater."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"5992","DOI":"10.1021\/acsnano.7b01894","article-title":"Fully Stretchable Optoelectronic Sensors Based on Colloidal Quantum Dots for Sensing Photoplethysmographic Signals","volume":"11","author":"Kim","year":"2017","journal-title":"ACS Nano"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"4496","DOI":"10.1038\/ncomms5496","article-title":"Conformable amplified lead zirconate titanate sensors with enhanced piezoelectric response for cutaneous pressure monitoring","volume":"5","author":"Dagdeviren","year":"2014","journal-title":"Nat. Commun."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"e1500661","DOI":"10.1126\/sciadv.1500661","article-title":"Fingertip Skin-inspired Microstructured Ferroelectric Skins Discriminate Static\/dynamic Pressure and Temperature Stimuli","volume":"1","author":"Park","year":"2015","journal-title":"Sci. Adv."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3640","DOI":"10.1002\/adfm.201600008","article-title":"Flexible Polymer Transducers for Dynamic Recognizing Physiological Signals","volume":"26","author":"Han","year":"2016","journal-title":"Adv. Funct. Mater."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2010962","DOI":"10.1002\/adfm.202010962","article-title":"Muscle Fibers Inspired High-Performance Piezoelectric Textiles for Wearable Physiological Monitoring","volume":"31","author":"Su","year":"2021","journal-title":"Adv. Funct. Mater."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Nguyen, T.V., and Ichiki, M. (2019). MEMS-Based Sensor for Simultaneous Measurement of Pulse Wave and Respiration Rate. Sensors, 19.","DOI":"10.3390\/s19224942"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"3451","DOI":"10.1002\/adma.201305182","article-title":"Highly stretchable resistive pressure sensors using a conductive elastomeric composite on a micropyramid array","volume":"26","author":"Choong","year":"2014","journal-title":"Adv. Mater."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1859","DOI":"10.1038\/ncomms2832","article-title":"Flexible polymer transistors with high pressure sensitivity for application in electronic skin and health monitoring","volume":"4","author":"Schwartz","year":"2013","journal-title":"Nat. Commun."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"634","DOI":"10.1002\/adma.201403807","article-title":"Highly skin-conformal microhairy sensor for pulse signal amplification","volume":"27","author":"Pang","year":"2015","journal-title":"Adv. Mater."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"6269","DOI":"10.1038\/ncomms7269","article-title":"Flexible suspended gate organic thin-film transistors for ultra-sensitive pressure detection","volume":"6","author":"Zang","year":"2015","journal-title":"Nat. Commun."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"55747","DOI":"10.1021\/acsami.1c17318","article-title":"Graded Microstructured Flexible Pressure Sensors with High Sensitivity and an Ultrabroad Pressure Range for Epidermal Pulse Monitoring","volume":"13","author":"Wang","year":"2021","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"107710","DOI":"10.1016\/j.nanoen.2022.107710","article-title":"Flexible pressure sensor for high-precision measurement of epidermal arterial pulse","volume":"102","author":"Wang","year":"2022","journal-title":"Nano Energy"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1316","DOI":"10.1002\/adma.201404794","article-title":"Eardrum-inspired active sensors for self-powered cardiovascular system characterization and throat-attached anti-interference voice recognition","volume":"27","author":"Yang","year":"2015","journal-title":"Adv. Mater."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"907","DOI":"10.1016\/j.bios.2015.10.062","article-title":"Ultrasensitive, passive and wearable sensors for monitoring human muscle motion and physiological signals","volume":"77","author":"Cai","year":"2016","journal-title":"Biosens. Bioelectron."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"104460","DOI":"10.1016\/j.nanoen.2020.104460","article-title":"Hierarchical elastomer tuned self-powered pressure sensor for wearable multifunctional cardiovascular electronics","volume":"70","author":"Chen","year":"2020","journal-title":"Nano Energy"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"e1804944","DOI":"10.1002\/adma.201804944","article-title":"A Stretchable Yarn Embedded Triboelectric Nanogenerator as Electronic Skin for Biomechanical Energy Harvesting and Multifunctional Pressure Sensing","volume":"30","author":"Dong","year":"2018","journal-title":"Adv. Mater."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1016\/j.nanoen.2019.02.057","article-title":"Expandable microsphere-based triboelectric nanogenerators as ultrasensitive pressure sensors for respiratory and pulse monitoring","volume":"59","author":"Liu","year":"2019","journal-title":"Nano Energy"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1703456","DOI":"10.1002\/adma.201703456","article-title":"Self-Powered Pulse Sensor for Antidiastole of Cardiovascular Disease","volume":"29","author":"Ouyang","year":"2017","journal-title":"Adv. Mater."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"105614","DOI":"10.1016\/j.nanoen.2020.105614","article-title":"Self-powered ultrasensitive pulse sensors for noninvasive multi-indicators cardiovascular monitoring","volume":"81","author":"Xu","year":"2021","journal-title":"Nano Energy"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"17","DOI":"10.4103\/ijt.ijt_46_20","article-title":"Trichoscopy of Pressure-Induced Alopecia and Alopecia Areata: A Comparative Study","volume":"14","author":"Neema","year":"2022","journal-title":"Int. J. Trichology"},{"key":"ref_30","first-page":"11","article-title":"Hair and Nail Conditions: Alopecia Evaluation","volume":"517","author":"Wu","year":"2022","journal-title":"FP Essent."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"164832","DOI":"10.4061\/2011\/164832","article-title":"A brief journey into the history of the arterial pulse","volume":"2011","author":"Ghasemzadeh","year":"2011","journal-title":"Cardiol. Res. Pract."},{"key":"ref_32","first-page":"1415","article-title":"Variations in Non-invasive Radial Artery Pulse Waveform at Different Measuring Positions","volume":"2008","author":"Lee","year":"2008","journal-title":"Annu. Int. Conf. IEEE Eng. Med. Biol. Soc."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Wang, T.W., and Lin, S.F. (2020). Wearable Piezoelectric-Based System for Continuous Beat-to-Beat Blood Pressure Measurement. Sensors, 20.","DOI":"10.3390\/s20030851"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1007\/s13246-019-00813-x","article-title":"Non-invasive Continuous Blood Pressure Monitoring Systems: Current and Proposed Technology Issues and Challenges","volume":"43","author":"Rastegar","year":"2019","journal-title":"Phys. Eng. Sci. Med."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Zambrana-Vinaroz, D., Vicente-Samper, J.M., Juan, C.G., Esteve-Sala, V., and Sabater-Navarro, J.M. (2019). Non-Invasive Device for Blood Pressure Wave Acquisition by Means of Mechanical Transducer. Sensors, 19.","DOI":"10.3390\/s19194311"},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Hsieh, Y.-Y., Wu, C.-D., Lu, S.-S., and Tsao, Y. (2017, January 17\u201319). A Linear Regression Model with Dynamic Pulse Transit Time Features for Noninvasive Blood Pressure Prediction. Proceedings of the 2016 IEEE Biomedical Circuits and Systems Conference (BIOCAS), Shanghai, China.","DOI":"10.1109\/BioCAS.2016.7833867"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1007\/s13534-019-00096-x","article-title":"Pulse Transit Time Technique for Cuffless Unobtrusive Blood Pressure Measurement: From Theory to Algorithm","volume":"9","author":"Ding","year":"2019","journal-title":"Biomed. Eng. Lett."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/1\/45\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:45:20Z","timestamp":1760147120000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/1\/45"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,12,21]]},"references-count":37,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2023,1]]}},"alternative-id":["s23010045"],"URL":"https:\/\/doi.org\/10.3390\/s23010045","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,12,21]]}}}