In this study, we report a comprehensive time-resolved spectroscopic investigation of the excited-state deactivation mechanism in three push-pull isomers characterized by a phenothiazine electron donor, a benzothiazole electron acceptor, and a phenyl π-bridge where the connection is realized at the relative , , and positions. Spin-orbit charge-transfer-induced intersystem crossing takes place with high yield in these all-organic donor-acceptor compounds, leading also to efficient production of singlet oxygen. Our spectroscopic results give clear evidence of room-temperature phosphorescence not only in solid-state host-guest matrices but also in highly biocompatible aggregates of these isomers produced in water dispersions, as rarely reported in the literature. Moreover, aggregates of the isomers could be internalized by lung cancer and melanoma cells and display bright luminescence without any dark cytotoxic effect. On the other hand, the isomers showed significant cellular phototoxicity against the tumor cells due to light-induced reactive oxygen species generation. Our findings strongly suggest that nanoaggregates of the investigated isomers are promising candidates for imaging-guided photodynamic therapy.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9940226 | PMC |
http://dx.doi.org/10.1021/acs.jpcb.2c07717 | DOI Listing |
J Phys Chem A
January 2025
Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
The strategy of designing efficient room-temperature phosphorescence (RTP) emitters based on hydrogen bond interactions has attracted great attention in recent years. However, the regulation mechanism of the hydrogen bond on the RTP property remains unclear, and corresponding theoretical investigations are highly desired. Herein, the structure-property relationship and the internal mechanism of the hydrogen bond effect in regulating the RTP property are studied through the combination of quantum mechanics and molecular mechanics methods (QM/MM) coupled with the thermal vibration correlation function method.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2025
Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Institute of Applied Chemistry, Guizhou University, Guiyang 550025, China. Electronic address:
A bromophenylpyridine derivative (N1) was designed, synthesized, and the molecule was incorporated into the cavity of the cucurbit[8]uril (Q[8]) as a guest to form a 2:1 host-guest complex. This complex demonstrates good room temperature phosphorescence (RTP) properties in aqueous solution. The host-guest interaction and optical properties of N1@Q[8] in aqueous solution were studied by means of H NMR, ultraviolet-visible absorption spectroscopy, fluorescence spectroscopy, phosphorescence spectroscopy, scanning electron microscopy and inverted fluorescence microscopy.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
NCL: CSIR National Chemical Laboratory, Organic Chemistry, Dr. Homi Bhabha Road, 411008, Pune, INDIA.
The cutouts of graphene sheets, particularly those with a nonplanar topology, present vast opportunities for advancement. Even a slight deviation from the planar structure can lead to intriguing (chiro)optical features for helically twisted nanographenes. In this context, we introduce two regioisomeric π-extended nanographenes that exhibit distinct excited-state characteristics.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
Organic room-temperature phosphorescence (RTP) emitters with long lifetimes, high exciton utilizations, and tunable emission properties show promising applications in organic light-emitting diodes (OLEDs) and biomedical fields. Their excited-state properties are highly related to single molecular structure, aggregation morphology, and external stimulus (such as hydrostatic pressure effect). To gain a deeper understanding and effectively regulate the key factors of luminescent efficiency and lifetime for RTP emitters, we employ the thermal vibration correlation function (TVCF) theory coupled with quantum mechanics/molecular mechanics (QM/MM) calculations to investigate the photophysical properties of three reported RTP crystals (Bp-OEt, Xan-OEt, and Xan-OMe) with elastic/plastic deformation.
View Article and Find Full Text PDFJ Phys Chem Lett
January 2025
College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China.
Organic room-temperature phosphorescent (RTP) materials have wide-ranging applications in anticounterfeiting, biodiagnostics, and optoelectronic devices due to their unique properties. However, it remains a challenge to give organic RTP materials dynamic tunability to satisfy the demands of various advanced applications. Herein, we propose an effective strategy to precisely modulate phosphorescent performance by incorporating dynamic metal-ligand coordination within a host-guest doped system.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!