Han, Sung Ju Seo, Min Cho, Min Gyeong Kwon, Young-Wan Lim, Sang-Ho Han, Seung Hee 2024-01-19T15:30:43Z 2024-01-19T15:30:43Z 2022-01-10 2021-02-26 2574-0970 https://pubs.kist.re.kr/handle/201004/117382 Fluorescent nanodiamonds (FNDs) contain nitrogen vacancy (NV) centers that emit photostable fluorescence in the wavelength range between 500 and 800 nm, which does not overlap with cellular autofluorescence. Also, the FNDs possess excellent biocompatibility. For this reason, they are promising fluorescent probes for background-free imaging for biomedical applications. The FNDs used in vivo, however, should be <10 nm for renal clearance. In this study, we introduce sub-5 nm nanodiamonds fabricated by mesh-assisted plasma immersion ion implantation as fluorescent probes for biomedical purposes. The FNDs generated with this process emitted bright fluorescence with their photoluminescence (PL) peaks centered at 620 nm. Atomic force microscopy, transmission electron microscopy, and X-ray diffraction (XRD) measurements confirmed that the average diameter of the treated sample was <5 nm. Moreover, the electron paramagnetic resonance analysis results demonstrated that the 7.5 min ion-implanted FND sample contained twice as much NV- center concentration as the annealed, oxidized, and acid-cleaned detonation nanodiamonds (DNDs). Finally, the purity of samples was confirmed using X-ray photoelectron spectroscopy (XPS) and XRD data. This study opens an avenue toward sub-5 nm FNDs with promising applications as fluorescent probes in biomedicine. English AMER CHEMICAL SOC Sub-5 nm Nanodiamonds Fabricated by Plasma Immersion Ion Implantation as Fluorescent Probes Article 10.1021/acsanm.1c00038 1 ACS APPLIED NANO MATERIALS, v.4, no.2, pp.2238 - 2246 ACS APPLIED NANO MATERIALS 4 2 2238 2246 scie scopus 000624546800134 2-s2.0-85101031905 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Science & Technology - Other Topics Materials Science Article fluorescent nanodiamonds (FNDs) sub-5 nm FNDs large-scale production of FNDs detonation nanodiamonds (DNDs) plasma immersion ion implantation (PIII) mesh-assisted PIII nitrogen vacancy center (NV center) fluorescent probes