title: On-off regulation of 19F magnetic resonance signals based on pH-sensitive PEGylated nanogels for potential tumor-specific smart 19F MRI probes.
abstract: The pH-sensitive PEGylated nanogels constructed from tethered PEG chains and a polyamine gel core containing 19F compounds showed remarkable on-off regulation of 19F MR (magnetic resonance) signals in response to the extracellular pH (6.5) of the tumor environment, even in the presence of 90% fetal bovine serum, due to the increase in the molecular motion of the 19F compounds through the hydrophilic-hydrophobic (volume-phase) transition of the polyamine gel core. Eventually, an appreciably enhanced 19F MR signal at an extremely low 19F compound concentration (approximately 55 microM) was achieved, demonstrating the utility of these nanogels as solid tumor-specific smart 19F MRI probes.
authors.affiliation: Graduate School of Pure and Applied Sciences, Graduate School of Comprehensive Human, University of Tsukuba, 1-1-1 Ten-noudai, Tsukuba, Ibaraki 305-8573, Japan.
authors.forename: Motoi
authors.initials: M
authors.lastname: Oishi
authors.forename: Shogo
authors.initials: S
authors.lastname: Sumitani
authors.forename: Yukio
authors.initials: Y
authors.lastname: Nagasaki
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000032:analysis; D002417:Cattle; D003470:Culture Media / Q000494:pharmacology; D005312:Fetal Blood; D005462:Fluorine Radioisotopes; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D000080385:Nanogels; D009369:Neoplasms / Q000473:pathology*; D011073:Polyamines / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry*; D011094:Polyethyleneimine / Q000737:chemistry*; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D003470:Culture Media; D005462:Fluorine Radioisotopes; D007202:Indicators and Reagents; D000080385:Nanogels; D011073:Polyamines; C413692:polyethylene glycol polyethyleneimine nanogel; D011092:Polyethylene Glycols; D011094:Polyethyleneimine