title: Silica-coated bismuth sulfide nanorods as multimodal contrast agents for a non-invasive visualization of the gastrointestinal tract.
abstract: Non-invasive and real-time imaging of the gastrointestinal (GI) tract is particularly desirable for research and clinical studies of patients with symptoms arising from gastrointestinal diseases. Here, we designed and fabricated silica-coated bismuth sulfide nanorods (Bi2S3@SiO2 NRs) for a non-invasive spatial-temporally imaging of the GI tract. The Bi2S3 NRs were synthesized by a facile solvothermal method and then coated with a SiO2 layer to improve their biocompatibility and stability in the harsh environments of the GI tract, such as the stomach and the small intestine. Due to their strong X-ray- and near infrared-absorption abilities, we demonstrate that, following oral administration in mice, the Bi2S3@SiO2 NRs can be used as a dual-modal contrast agent for the real-time and non-invasive visualization of NRs distribution and the GI tract via both X-ray computed tomography (CT) and photoacoustic tomography (PAT) techniques. Importantly, integration of PAT with CT provides complementary information on anatomical details with high spatial resolution. In addition, we use Caenorhabditis Elegans (C. Elegans) as a simple model organism to investigate the biological response of Bi2S3@SiO2 NRs by oral administration. The results indicate that these NRs can pass through the GI tract of C. Elegans without inducing notable toxicological effects. The above results suggest that Bi2S3@SiO2 NRs pave an alternative way for the fabrication of multi-modal contrast agents which integrate CT and PAT modalities for a direct and non-invasive visualization of the GI tract with low toxicity.
authors.affiliation: CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P. R. China. yanliang@ihep.ac.cn zjgu@ihep.ac.cn zhaoyuliang@ihep.ac.cn.
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Zheng
authors.forename: Junxin
authors.initials: J
authors.lastname: Shi
authors.forename: Yang
authors.initials: Y
authors.lastname: Bu
authors.forename: Gan
authors.initials: G
authors.lastname: Tian
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhang
authors.forename: Wenyan
authors.initials: W
authors.lastname: Yin
authors.forename: Bifen
authors.initials: B
authors.lastname: Gao
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Yang
authors.forename: Zhongbo
authors.initials: Z
authors.lastname: Hu
authors.forename: Xiangfeng
authors.initials: X
authors.lastname: Liu
authors.forename: Liang
authors.initials: L
authors.lastname: Yan
authors.forename: Zhanjun
authors.initials: Z
authors.lastname: Gu
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001729:Bismuth / Q000737:chemistry; D017173:Caenorhabditis elegans / Q000254:growth & development / Q000378:metabolism; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003287:Contrast Media / Q000737:chemistry*; D005260:Female; D041981:Gastrointestinal Tract / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008856:Microscopy, Fluorescence; D043942:Nanotubes / Q000737:chemistry* / Q000633:toxicity; D061088:Photoacoustic Techniques; D012822:Silicon Dioxide / Q000737:chemistry; D013440:Sulfides / Q000737:chemistry; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D013440:Sulfides; D012822:Silicon Dioxide; D001729:Bismuth; C049897:bismuth sulfide