title: A Feasibility Study of Nonlinear Spectroscopic Measurement of Magnetic Nanoparticles Targeted to Cancer Cells.
abstract: Magnetic nanoparticles (MNPs) are an emerging platform for targeted diagnostics in cancer. An important component needed for translation of MNPs is the detection and quantification of targeted MNPs bound to tumor cells.
  
  
  
  This study explores the feasibility of a multifrequency nonlinear magnetic spectroscopic method that uses excitation and pickup coils and is capable of discriminating between quantities of bound and unbound MNPs in 0.5 ml samples of KB and Igrov human cancer cell lines. The method is tested over a range of five concentrations of MNPs from 0 to 80 μg/ml and five concentrations of cells from 50 to 400 000 count per ml.
  
  
  
  A linear model applied to the magnetic spectroscopy data was able to simultaneously measure bound and unbound MNPs with agreement between the model-fit and lab assay measurements (p < 0.001). The detectable iron of the presented method to bound and unbound MNPs was < 2 μg in a 0.5 ml sample. The linear model parameters used to determine the quantities of bound and unbound nanoparticles in KB cells were also used to measure the bound and unbound MNP in the Igrov cell line and vice versa.
  
  
  
  Nonlinear spectroscopic measurement of MNPs may be a useful method for studying targeted MNPs in oncology.
  
  
  
  Determining the quantity of bound and unbound MNP in an unknown sample using a linear model represents an exciting opportunity to translate multifrequency nonlinear spectroscopy methods to in vivo applications where MNPs could be targeted to cancer cells.
authors.forename: Bradley W
authors.initials: BW
authors.lastname: Ficko
authors.forename: Christian
authors.initials: C
authors.lastname: NDong
authors.forename: Paolo
authors.initials: P
authors.lastname: Giacometti
authors.forename: Karl E
authors.initials: KE
authors.lastname: Griswold
authors.forename: Solomon G
authors.initials: SG
authors.lastname: Diamond
mesh_terms: D045744:Cell Line, Tumor; D016503:Drug Delivery Systems / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005240:Feasibility Studies; D006801:Humans; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D009374:Neoplasms, Experimental / Q000737:chemistry*; D017711:Nonlinear Dynamics; D010316:Particle Size; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013057:Spectrum Analysis / Q000295:instrumentation* / Q000379:methods*
chemical_list: D058185:Magnetite Nanoparticles