Ultra-small Bi2S3 nanoparticles are potential contrast agents for high-sensitive CT imaging. However, the expensive and harmful synthesis process limited their further application. Herein, an economical and low-toxic process was developed by employing S powders as sulfur precursors for large-scale preparation of ultra-small Bi2S3 nanoparticles. The as-prepared ultra-small Bi2S3 nanoparticles were modified with amine-terminated poly(ethylene glycol) (PEG) to produce water-soluble contrast agents. In vitro experiment results suggested that the ultra-small Bi2S3-PEG nanoparticles were low cytotoxic and superior contrast agents. In vivo experiments demonstrated that the ultra-small Bi2S3-PEG nanoparticles were preferred contrast agents for long-term and high-sensitive CT imaging.

中文翻译：

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用于高灵敏度 CT 成像的超小 Bi2S3 纳米粒子的经济合成

超小 Bi2S3 纳米粒子是高灵敏度 CT 成像的潜在造影剂。然而，昂贵且有害的合成过程限制了它们的进一步应用。在此，开发了一种经济、低毒的工艺，采用 S 粉末作为硫前体，用于大规模制备超小 Bi2S3 纳米颗粒。所制备的超小Bi2S3 纳米粒子用胺封端的聚（乙二醇）（PEG） 修饰以生产水溶性造影剂。体外实验结果表明超小Bi2S3-PEG纳米粒子具有低细胞毒性和优越的造影剂。体内实验表明，超小 Bi2S3-PEG 纳米颗粒是长期和高灵敏度 CT 成像的首选造影剂。