title: The long-term stability and biocompatibility of fluorescent nanodiamond as an in vivo contrast agent.
abstract: Nanocarbon is a promising type of biomaterial for diagnostic and therapeutic applications. Fluorescent nanodiamond (FND) containing nitrogen-vacancy centers as built-in fluorophores is a new addition to the nanocarbon family. Here, we study the long-term stability and biocompatibility of 100-nm FNDs in rats through intraperitoneal injection over 5 months and develop the potential application of this biomaterial for sentinel lymph node mapping in a mouse model. From both in vivo and ex vivo fluorescence imaging as well as transmission electron microscopy, we found that the intradermally administered FND particles can be drained from the injection sites by macrophages and selectively accumulated in the axillary lymph nodes of the treated mice. Our measurements of water consumption, fodder consumption, body weight, and organ index showed no significant difference between control and FND-treated groups of the rats. Histopathological analysis of various tissues and organs indicated that FNDs are non-toxic even when a large quantity, up to 75 mg/kg body weight, of the particles was administered intraperitoneally to the living animals. With the properties of wide-ranging biocompatibility and perfect chemical and photophysical stability, FND is well suited for use as a contrast agent for long-term in vivo imaging.
authors.affiliation: Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10672, Taiwan, ROC.
authors.forename: V
authors.initials: V
authors.lastname: Vaijayanthimala
authors.forename: Po-Yun
authors.initials: PY
authors.lastname: Cheng
authors.forename: Shih-Hua
authors.initials: SH
authors.lastname: Yeh
authors.forename: Kuang-Kai
authors.initials: KK
authors.lastname: Liu
authors.forename: Cheng-Hsiang
authors.initials: CH
authors.lastname: Hsiao
authors.forename: Jui-I
authors.initials: JI
authors.lastname: Chao
authors.forename: Huan-Cheng
authors.initials: HC
authors.lastname: Chang
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology; D001835:Body Weight / Q000187:drug effects; D003287:Contrast Media; D005456:Fluorescent Dyes; D007274:Injections, Intraperitoneal; D008198:Lymph Nodes / Q000187:drug effects / Q000473:pathology / Q000648:ultrastructure; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D058612:Nanodiamonds / Q000008:administration & dosage / Q000648:ultrastructure; D009928:Organ Specificity / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012710:Serum Albumin, Bovine / Q000378:metabolism; D012867:Skin / Q000187:drug effects / Q000473:pathology; D013997:Time Factors
chemical_list: D001672:Biocompatible Materials; D003287:Contrast Media; D005456:Fluorescent Dyes; D058612:Nanodiamonds; D012710:Serum Albumin, Bovine