{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T02:13:23Z","timestamp":1777428803953,"version":"3.51.4"},"reference-count":39,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,3,13]],"date-time":"2022-03-13T00:00:00Z","timestamp":1647129600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Natural Science Foundation of Hunan Province","award":["2020JJ4346"],"award-info":[{"award-number":["2020JJ4346"]}]},{"name":"the Foundation of Department of Education of Hunan Province","award":["20K063"],"award-info":[{"award-number":["20K063"]}]},{"name":"Degree &amp; Postgraduate Education Reform Project of Hunan Province","award":["2019JGYB130"],"award-info":[{"award-number":["2019JGYB130"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Sensitive simultaneous electrochemical sensing of phytohormones indole-3-acetic acid and salicylic acid based on a novel poly(L-Proline) nanoparticles\u2013carbon dots composite consisting of multiwalled carbon nanotubes was reported in this study. The poly(L-Proline) nanoparticles\u2013carbon dots composite was facilely prepared by the hydrothermal method, and L-Proline was used as a monomer and carbon source for the preparation of poly(L-Proline) nanoparticles and carbon dots, respectively. Then, the poly(L-Proline) nanoparticles\u2013carbon dots\u2013multiwalled carbon nanotubes composite was prepared by ultrasonic mixing of poly(L-Proline) nanoparticles\u2013carbon dots composite dispersion and multiwalled carbon nanotubes. Scanning electron microscope, transmission electron microscope, Fourier transform infrared spectroscopy, ultraviolet visible spectroscopy, energy dispersive spectroscopy, cyclic voltammetry, electrochemical impedance spectroscopy, and linear sweep voltammetry were used to characterize the properties of the composite. poly(L-Proline) nanoparticles were found to significantly enhance the conductivity and sensing performance of the composite. Under optimal conditions, the composite-modified electrode exhibited a wide linear range from 0.05 to 25 \u03bcM for indole-3-acetic acid and from 0.2 to 60 \u03bcM for salicylic acid with detection limits of 0.007 \u03bcM and 0.1 \u03bcM (S\/N = 3), respectively. In addition, the proposed sensor was also applied to simultaneously test indole-3-acetic acid and salicylic acid in real leaf samples with satisfactory recovery.<\/jats:p>","DOI":"10.3390\/s22062222","type":"journal-article","created":{"date-parts":[[2022,3,13]],"date-time":"2022-03-13T21:44:17Z","timestamp":1647207857000},"page":"2222","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Simultaneous Electrochemical Sensing of Indole-3-Acetic Acid and Salicylic Acid on Poly(L-Proline) Nanoparticles\u2013Carbon Dots\u2013Multiwalled Carbon Nanotubes Composite-Modified Electrode"],"prefix":"10.3390","volume":"22","author":[{"given":"Mengxue","family":"Li","sequence":"first","affiliation":[{"name":"College of Chemistry and Materials Science, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yiwen","family":"Kuang","sequence":"additional","affiliation":[{"name":"College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ziyan","family":"Fan","sequence":"additional","affiliation":[{"name":"College of Chemistry and Materials Science, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8872-8551","authenticated-orcid":false,"given":"Xiaoli","family":"Qin","sequence":"additional","affiliation":[{"name":"College of Chemistry and Materials Science, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shiyu","family":"Hu","sequence":"additional","affiliation":[{"name":"College of Chemistry and Materials Science, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhanning","family":"Liang","sequence":"additional","affiliation":[{"name":"College of Chemistry and Materials Science, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qilin","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Chemistry and Materials Science, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Weizhong","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Chemistry and Materials Science, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Birui","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Chemistry and Materials Science, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7616-0770","authenticated-orcid":false,"given":"Zhaohong","family":"Su","sequence":"additional","affiliation":[{"name":"College of Chemistry and Materials Science, Hunan Agricultural University, Changsha 410128, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"473","DOI":"10.1007\/s11103-008-9435-0","article-title":"Role of plant hormones in plant defence responses","volume":"69","author":"Bari","year":"2009","journal-title":"Plant Mol. 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