title: Cellular uptake and imaging studies of glycosylated silica nanoprobe (GSN) in human colon adenocarcinoma (HT 29 cell line).
abstract: OBJECTIVE
  In recent years, molecular imaging by magnetic resonance imaging (MRI) has gained prominence in the detection of tumor cells. The scope of this study is on molecular imaging and on the cellular uptake study of a glycosylated silica nanoprobe (GSN).
  
  
  METHODS
  In this study, intracellular uptake (HT 29 cell line) of GSN was analyzed quantitatively and qualitatively with inductively coupled plasma atomic emission spectroscopy, flow cytometry, and fluorescent microscopy. In vitro and in vivo relaxometry of this nanoparticle was determined using a 3 Tesla MRI; biodistribution of GSN and Magnevist® were measured in different tissues.
  
  
  RESULTS
  Results suggest that the cellular uptake of GSN was about 70%. The r1 relaxivity of this nanoparticle in the cells was measured to be 12.9 ± 1.6 mM(-1) s(-1) and on a per lanthanide gadolinium (Gd(3+)) basis. Results also indicate an average cellular uptake of 0.7 ± 0.009 pg Gd(3+) per cell. It should be noted that 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay demonstrated that the cells were effectively labeled without cytotoxicity, and that using MRI for quantitative estimation of delivery and uptake of targeted contrast agents and early detection of human colon cancer cells using targeted contrast agents, is feasible.
  
  
  CONCLUSIONS
  These results showed that GSN provided a critical guideline in selecting these nanoparticles as an appropriate contrast agent for nanomedicine applications.
authors.affiliation: Biomedical Engineering and Medical Physics Department, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Bita
authors.initials: B
authors.lastname: Mehravi
authors.forename: Mohsen
authors.initials: M
authors.lastname: Ahmadi
authors.forename: Massoud
authors.initials: M
authors.lastname: Amanlou
authors.forename: Ahmad
authors.initials: A
authors.lastname: Mostaar
authors.forename: Mehdi Shafiee
authors.initials: MS
authors.lastname: Ardestani
authors.forename: Negar
authors.initials: N
authors.lastname: Ghalandarlaki
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000737:chemistry / Q000493:pharmacokinetics*; D005944:Glucosamine / Q000737:chemistry; D019073:HT29 Cells; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D057054:Molecular Imaging / Q000379:methods*; D053758:Nanoparticles / Q000737:chemistry*; D019047:Phantoms, Imaging; D012822:Silicon Dioxide / Q000737:chemistry / Q000493:pharmacokinetics*; D014018:Tissue Distribution
chemical_list: D003287:Contrast Media; D012822:Silicon Dioxide; D005944:Glucosamine
keywords: MRI; cellular uptake; contrast agent; glucosamine; mesoporous silica nanospheres; molecular imaging