Fluorescent carbonaceous nanospheres as biological probe for noninvasive brain imaging

• Published in: Journal of colloid and interface science 2014-12, Vol.436 (436), p.227-233
• Main Authors: Qian, Jun, Ruan, Shaobo, Cao, Xi, Cun, Xingli, Chen, Jiantao, Shen, Shun, Jiang, Xinguo, He, Qin, Zhu, Jianhua, Gao, Huile
• Format: Article
• Language: English
• Subjects: Animals; Biocompatibility; Biocompatible Materials; Biological; Biological probe; Biomedical materials; Brain; Brain imaging; Carbon - chemistry; Chemistry; Colloidal state and disperse state; Diagnostic Imaging; Exact sciences and technology; Fluorescent carbonaceous nanospheres; Fluorescent Dyes - chemistry; General and physical chemistry; Imaging; In vivo testing; In vivo tests; Male; Mice; Nanospheres - chemistry; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Surgical implants
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2014.08.059

[Display omitted] •A new kind of fluorescent carbonaceous nanospheres (CDs) was prepared using glutamic acid and glucose as the precursors.•The prepared CDs possessed excellent optical properties and good biocompatibility.•CDs were used as biological probe for cell imaging in vitro.•We report the application of CDs in non-invasive brain imaging. Fluorescent carbonaceous nanospheres (CDs) have generated much excitement in bioimaging because of their impressive fluorescent properties and good biocompatibility. In this study, we evaluated the potential application of CDs in noninvasive brain imaging. A new kind of CDs was prepared by a heat treating method using glutamic acid and glucose as the precursors. The hydrated diameter and zeta potential of CDs were 101.1nm (PDI=0.110) and −22.4mV respectively. Palpable emission spectrum could be observed from 400nm to 600nm when excited at corresponding wavelength, suggesting CDs could be used as a noninvasive bio-probe for in vivo imaging. Additionally, several experiments indicated that CDs possess good serum stability and hemocompatibility with low cytotoxicity. In vitro, the CDs could be efficiently taken up by bEnd.3 cells in a concentration- and time-dependent manner. In vivo, CDs could be used for noninvasive brain imaging due to its high accumulation in brain region, which was demonstrated by in vivo imaging and ex vivo tissue imaging. Moreover, the fluorescent distribution in tissue slice showed CDs accumulated in brain with high intensity. In conclusion, CDs were prepared using a simple one-step method with unique optical and good biological properties and could be used for noninvasive brain imaging.