title: Synthesis and characterization of PEGylated polyethylenimine-entrapped gold nanoparticles for blood pool and tumor CT imaging.
abstract: The synthesis and characterization of gold nanoparticles (AuNPs) entrapped within polyethylene glycol (PEG)-modified polyethylenimine (PEI) for blood pool and tumor computed tomography (CT) imaging are reported. In this approach, partially PEGylated PEI was used as a template for AuNP synthesis, followed by acetylating the PEI remaining surface amines. The synthesized PEGylated PEI-entrapped AuNPs (Au PENPs) were characterized via different methods. Our results reveal that the synthesized Au PENPs can be tuned to have an Au core size in a range of 1.9-4.6 nm and to be water-soluble, stable, and noncytotoxic in a studied concentration range. With a demonstrated better X-ray attenuation property than that of clinically used iodinated small molecular contrast agent (e.g., Omnipaque) and the prolonged half-decay time (11.2 h in rat) confirmed by pharmacokinetics studies, the developed PEGylated Au PENPs enabled efficient and enhanced blood pool CT imaging with imaging time up to 75 min. Likewise, thanks to the enhanced permeability and retention effect, the PEGylated Au PENPs were also able to be used as a contrast agent for effective CT imaging of a tumor model. With the proven organ biocompatibility by histological studies, the designed PEGylated Au PENPs may hold great promise to be used as contrast agents for CT imaging of a variety of biological systems. The significance of this study is that rather than the use of dendrimers as templates, cost-effective branched polymers (e.g., PEI) can be used as templates to generate functionalized AuNPs for CT imaging applications.
authors.affiliation: College of Chemistry, Chemical Engineering and Biotechnology, Donghua University , Shanghai 201620, People's Republic of China.
authors.forename: Benqing
authors.initials: B
authors.lastname: Zhou
authors.forename: Linfeng
authors.initials: L
authors.lastname: Zheng
authors.forename: Chen
authors.initials: C
authors.lastname: Peng
authors.forename: Du
authors.initials: D
authors.lastname: Li
authors.forename: Jingchao
authors.initials: J
authors.lastname: Li
authors.forename: Shihui
authors.initials: S
authors.lastname: Wen
authors.forename: Mingwu
authors.initials: M
authors.lastname: Shen
authors.forename: Guixiang
authors.initials: G
authors.lastname: Zhang
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Shi
mesh_terms: D000818:Animals; D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D005260:Female; D015637:Gated Blood-Pool Imaging / Q000379:methods*; D006046:Gold / Q000493:pharmacokinetics; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D008297:Male; D053768:Metal Nanoparticles / Q000633:toxicity; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009369:Neoplasms / Q000000981:diagnostic imaging*; D009928:Organ Specificity / Q000187:drug effects; D010316:Particle Size; D011092:Polyethylene Glycols / Q000138:chemical synthesis; D011094:Polyethyleneimine / Q000138:chemical synthesis; D017207:Rats, Sprague-Dawley; D013056:Spectrophotometry, Ultraviolet; D014018:Tissue Distribution / Q000187:drug effects; D014057:Tomography, X-Ray Computed / Q000379:methods*; D023041:Xenograft Model Antitumor Assays
chemical_list: D011092:Polyethylene Glycols; D006046:Gold; D011094:Polyethyleneimine
keywords: PEGylation; blood pool CT imaging; gold nanoparticles; polyethylenimine; tumors