Amino-functionalized nitrogen-doped graphene quantum dots and silver-graphene based nanocomposites: Ultrafast charge transfer and a proof-of-concept study for bioimaging applications

KARATAY A., ERDENER ÇIRALI D., Gurcan C., Yildiz E., YILMAZER AKTUNA A., BOYACIOĞLU B., ...Daha Fazla

JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY, cilt.426, 2022 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 426
  • Basım Tarihi: 2022
  • Doi Numarası: 10.1016/j.jphotochem.2021.113741
  • Dergi Adı: JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Agricultural & Environmental Science Database, BIOSIS, Chemical Abstracts Core, Chimica, INSPEC
  • Anahtar Kelimeler: Amino functionalized N-doped GQDs, Ag nanocomposites, Ultrafast spectroscopy, Bioimaging, DFT method, OPTICAL-PROPERTIES, ENHANCED FLUORESCENCE, CARBON NANODOTS, NANOPARTICLES, PHOTOLUMINESCENCE, THERMOCHEMISTRY, CHEMISTRY
  • Ankara Üniversitesi Adresli: Evet

Özet

Recent advances in nanotechnology have led to the use of graphene quantum dots (GQDs) for functional imaging and cancer therapy. Thanks to the physicochemical properties of graphene, GQDs have been functionalized and modified to improve their biological properties. In this study, polyethyleneimine functionalized nitrogen-doped graphene quantum dots (PEI N-doped GQDs) and silver nanoparticles/nitrogen-doped graphene quantum dots (AgNPs/PEI N-doped GQDs) nanocomposites have been developed. The PEI N-doped GQDs show a strong emission spectrum at maximum 446 nm with 356 nm excitation wavelength while AgNPs/PEI N-doped GQDs nanocomposites indicate weak fluorescence intensity at maximum 446 nm with 344 nm excitation wavelength. Based on the femtosecond transient absorption spectroscopy measurements, this emission quenching can be attributed that the excited state lifetime of PEI N-doped GQDs decreasing in the presence of AgNPs due to ultrafast electron transfer from PEI N-doped GQDs to AgNPs. It is also supported by theoretical results sensing ability of AgNPs/PEI N-doped GQDs nanocomposite is better than that of PEI N-doped GQDs. When lung adenocarcinoma cells (A549) were treated with GQDs, material-specific fluorescent signals were obtained from the cytoplasm of cells only treated with Ag/PEI N-doped GQDs, as compared with N-doped GQDs. Overall, this study shows that Ag/PEI N-doped GQDs are promising nanosystems for bioimaging applications.