Hikaru Yorozuya, Noor E Ashrafi, Kazuya Sato, Ahatashamul Islam, Rikuto Fukae, Yusuke Tagashira, Toshifumi Iimori
{"title":"利用生物聚合物和尿素合成氮掺杂碳点及其荧光机理。","authors":"Hikaru Yorozuya, Noor E Ashrafi, Kazuya Sato, Ahatashamul Islam, Rikuto Fukae, Yusuke Tagashira, Toshifumi Iimori","doi":"10.3390/molecules30092068","DOIUrl":null,"url":null,"abstract":"<p><p>Fluorescent carbon dots are nontoxic nanoparticles composed of carbon, exhibiting advantageous properties for applications in bioimaging and functional materials. We present a methodology for synthesizing fluorescent nitrogen-doped carbon dots (N-CDs) using starch, a biopolymer, and urea as the sources of nitrogen, via the microwave-assisted hydrothermal method. Furthermore, the dependence of the fluorescence spectra and fluorescence quantum yield of N-CDs on the initial concentration of urea in the reactant solution was examined, thereby providing a comprehensive understanding of the influence of nitrogen doping on the CDs. The fluorescence of N-CDs was tunable by varying the excitation wavelength. Stronger fluorescence intensity was observed for a moist phosphate salt/N-CD composite, in contrast to the weaker fluorescence exhibited by a dried one. Fluorescence lifetime measurements revealed that the change in fluorescence intensity can be attributed to the suppression of the non-radiative deactivation process. This observation highlights the critical importance of the interaction between water molecules and surface functional groups in controlling the photophysics of the excited state of N-CDs.</p>","PeriodicalId":19041,"journal":{"name":"Molecules","volume":"30 9","pages":""},"PeriodicalIF":4.2000,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12073190/pdf/","citationCount":"0","resultStr":"{\"title\":\"Synthesis and Fluorescence Mechanism of Nitrogen-Doped Carbon Dots Utilizing Biopolymer and Urea.\",\"authors\":\"Hikaru Yorozuya, Noor E Ashrafi, Kazuya Sato, Ahatashamul Islam, Rikuto Fukae, Yusuke Tagashira, Toshifumi Iimori\",\"doi\":\"10.3390/molecules30092068\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Fluorescent carbon dots are nontoxic nanoparticles composed of carbon, exhibiting advantageous properties for applications in bioimaging and functional materials. We present a methodology for synthesizing fluorescent nitrogen-doped carbon dots (N-CDs) using starch, a biopolymer, and urea as the sources of nitrogen, via the microwave-assisted hydrothermal method. Furthermore, the dependence of the fluorescence spectra and fluorescence quantum yield of N-CDs on the initial concentration of urea in the reactant solution was examined, thereby providing a comprehensive understanding of the influence of nitrogen doping on the CDs. The fluorescence of N-CDs was tunable by varying the excitation wavelength. Stronger fluorescence intensity was observed for a moist phosphate salt/N-CD composite, in contrast to the weaker fluorescence exhibited by a dried one. Fluorescence lifetime measurements revealed that the change in fluorescence intensity can be attributed to the suppression of the non-radiative deactivation process. This observation highlights the critical importance of the interaction between water molecules and surface functional groups in controlling the photophysics of the excited state of N-CDs.</p>\",\"PeriodicalId\":19041,\"journal\":{\"name\":\"Molecules\",\"volume\":\"30 9\",\"pages\":\"\"},\"PeriodicalIF\":4.2000,\"publicationDate\":\"2025-05-07\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12073190/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Molecules\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://doi.org/10.3390/molecules30092068\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"BIOCHEMISTRY & MOLECULAR BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Molecules","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.3390/molecules30092068","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
Synthesis and Fluorescence Mechanism of Nitrogen-Doped Carbon Dots Utilizing Biopolymer and Urea.
Fluorescent carbon dots are nontoxic nanoparticles composed of carbon, exhibiting advantageous properties for applications in bioimaging and functional materials. We present a methodology for synthesizing fluorescent nitrogen-doped carbon dots (N-CDs) using starch, a biopolymer, and urea as the sources of nitrogen, via the microwave-assisted hydrothermal method. Furthermore, the dependence of the fluorescence spectra and fluorescence quantum yield of N-CDs on the initial concentration of urea in the reactant solution was examined, thereby providing a comprehensive understanding of the influence of nitrogen doping on the CDs. The fluorescence of N-CDs was tunable by varying the excitation wavelength. Stronger fluorescence intensity was observed for a moist phosphate salt/N-CD composite, in contrast to the weaker fluorescence exhibited by a dried one. Fluorescence lifetime measurements revealed that the change in fluorescence intensity can be attributed to the suppression of the non-radiative deactivation process. This observation highlights the critical importance of the interaction between water molecules and surface functional groups in controlling the photophysics of the excited state of N-CDs.
期刊介绍:
Molecules (ISSN 1420-3049, CODEN: MOLEFW) is an open access journal of synthetic organic chemistry and natural product chemistry. All articles are peer-reviewed and published continously upon acceptance. Molecules is published by MDPI, Basel, Switzerland. Our aim is to encourage chemists to publish as much as possible their experimental detail, particularly synthetic procedures and characterization information. There is no restriction on the length of the experimental section. In addition, availability of compound samples is published and considered as important information. Authors are encouraged to register or deposit their chemical samples through the non-profit international organization Molecular Diversity Preservation International (MDPI). Molecules has been launched in 1996 to preserve and exploit molecular diversity of both, chemical information and chemical substances.