Bi2S3-SiO2 NRs/二氧化反应硅表层加硫铋納米棒多模态定影剂可作于肠内道GI激光散斑枝术

通过浓盐酸钡悬屏液看作X光显影液剂适用直肠激光散斑，原甚为人体拥有的非光降解名词解释他某些不良好的特性使其在直肠内串孔及肠内空间结构气象观测地方收到大上限；别常见的直肠内显影液剂就碘代团伙，但甚为本质X放射性元素吸附率较低，，因此普通须得大用量用能力高于好的体验，这总体会使病号造成碘皮肤过敏性的反应。

化学合成收获二氧化的硅涂覆的加硫铋納米棒（Bi2S3@SiO2 NRs）最为多模态定影剂用作直胃胃肠的无入侵性实时公交三维成像还有立即气象观测其在直胃胃肠下处的流过的过程（Scheme 1）。经二氧化的硅包复后，在胃及直肠中，Bi2S3@SiO2 NRs呈显出极为好的水阴离子型，生物体相融性并且 保持稳定义。借助TEM不错确定，Bi2S3 NRs宽约10 nm，宽约50 nm，稀有元素分折谱图提示 成功创业化学合成达到高色度的Bi2S3 NRs（Fig. 1），经二氧化物硅涂覆后，Bi2S3@SiO2 NRs显现单不集中性，SiO2壳层板厚为约为6 nm（Fig. 2）。

Fig. 1 Characterization of Bi2S3 NRs. (A) HAADF-STEM image and (B) HRTEM image of Bi2S3 NRs prepared by the solvothermal method. (C) Corresponding element mapping for Bi and S of the as-prepared Bi2S3 NRs. (D) EDS of the as-prepared Bi2S3 NRs.

Fig. 2 Characterization of Bi2S3@SiO2 NRs. (A) TEM image and (B) HRTEM image of as-prepared Bi2S3@SiO2 NRs. Inset: HAADF-STEM image of Bi2S3@SiO2 NRs. (C) Corresponding element mapping for Bi, S and Si of Bi2S3@SiO2 NRs. (D) EDS of Bi2S3@SiO2 NRs.

进行CT影像分折知道，跟随Bi₂S₃@SiO₂ NRs氨水浓度不断增加，其HU值清晰添加，同盐浓度下的HU值凸显少于硫酸钠钡，PAT网络信号随有机废气浓度增大也呈规则化提高感情（Fig. 3）。

Fig. 3 CT and PAT phantom images of Bi2S3@SiO2 NRs with different concentrations in vitro. (A) Plot of Hounsfield units (HU) values and of Bi2S3@SiO2 NRs and BaSO4 suspension versus the sample concentrations and CT phantom images of Bi2S3@SiO2 NRs and BaSO4 suspension samples with different concentrations. (B) Plot of the photoacoustic signal versus Bi2S3@SiO2 NRs concentrations and PAT phantom images of Bi2S3@SiO2 NRs aqueous solutions with different concentrations.

对Bi2S3@SiO2 NRs的海洋生物相融性开展测试，发现了16HBE与Bi2S3@SiO2 NRs共训练24 h后尚无出现出显眼的毒素，因此该激光束流入景色宜人隐杆线虫内后对其平均寿命也沒有显眼的干扰，这就情况说明Bi2S3@SiO2 NRs存在极其好的生物技术相溶性（Fig. 4）。

Fig. 4 Biosafety assessment of Bi2S3@SiO2 NRs by the C. Elegans model. (A) Bright field image of the NRs distribution in the GI tract of C. Elegans. Worms feed on NGM plates with Bi2S3@SiO2 NRs (1000 μg mL−1) transferred onto an agar pad after 1 h. (B) The distribution of food containing Bi2S3@SiO2 NRs (red arrows) in the intestine of the worm’s tail. (C) Effects of Bi2S3@SiO2 NRs with different concentrations on body length of C. Elegans. (D–H) Effects of Bi2S3@SiO2 NRs treatments on the accumulation of lipofuscin in age-synchronized worms. Representative fluorescent images of worms fed with 0, 1, 10, 100 and 1000 μg mL−1 Bi2S3@SiO2 NRs, respectively.

Bi2S3@SiO2 NRs以口服液的方法进人BALB/c裸鼠里面，经过CT及PAT对Bi2S3@SiO2 NRs来随时成相追踪定位，出现该微粒借助直消化道一点一点进行肠子较后以畜禽粪便的样式排除休外，该过程中中对直消化道的功能性不能显著的影响，阐述Bi2S3@SiO2 NRs对组织结构无倾入性影响（Fig. 5, 6, 7）。

Fig. 5 CT imaging of the GI tract in vivo. In vivo X-ray CT imaging of the GI tractin BALB/c nude mice at different intervals after oral administration of Bi2S3@SiO2 NRs.

Fig. 6 Enlarged images of CT images of the GI tract of mice 30 min post oral administration of Bi2S3@SiO2 NRs.

Fig. 7 PAT imaging of the GI tract in vivo. PAT cross-sectional image of the GI tract of BALB/c nude mice at different intervals after oral administration of Bi2S3@SiO2 NRs: stomach (ST), small intestine (SI) and large intestine