title: Folic acid-conjugated MnO nanoparticles as a T1 contrast agent for magnetic resonance imaging of tiny brain gliomas.
abstract: Detection of brain gliomas at the earliest stage is of great importance to improve outcomes, but it remains a most challenging task. In this study, oleic acid capped manganese oxide (MnO) nanoparticles (NPs) were prepared by the thermal decomposition of manganese oleate precursors and then transformed to water-dispersible MnO NPs by replacing oleic acid with N-(trimethoxysilylpropyl) ethylene diamine triacetic acid (TETT) silane. The covalently bonded TETT silane offers MnO NPs colloidal stability and abundant carboxylic functional groups allowing the further conjugation of the glioma-specific moiety, folic acid (FA). Moreover, the thin layer of TETT silane ensures a short distance between external Mn ion and water proton, which endows the FA-conjugated, TETT modified MnO (MnO-TETT-FA) NPs a longitudinal relaxivity as high as 4.83 mM(-1) s(-1). Accordingly, the in vivo magnetic resonance (MR) images demonstrated that MnO-TETT-FA NPs could efficiently enhance the MRI contrast for tiny brain gliomas. More importantly, due to the specificity of FA, MnO-TETT-FA NPs led to a clearer margin of the tiny glioma. This together with the good biocompatibility discloses the great potential of MnO-TETT-FA NPs as effective MRI contrast agents for the early diagnosis of brain gliomas.
authors.affiliation: Department of Neurosurgery, Beijing Sanbo Brain Hospital, Capital Medical University , Beijing 100093, P. R. China.
authors.forename: Ning
authors.initials: N
authors.lastname: Chen
authors.forename: Chen
authors.initials: C
authors.lastname: Shao
authors.forename: Yanming
authors.initials: Y
authors.lastname: Qu
authors.forename: Shuai
authors.initials: S
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Gu
authors.forename: Tingting
authors.initials: T
authors.lastname: Zheng
authors.forename: Ling
authors.initials: L
authors.lastname: Ye
authors.forename: Chunjiang
authors.initials: C
authors.lastname: Yu
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D003287:Contrast Media / Q000737:chemistry; D055088:Early Detection of Cancer; D005492:Folic Acid / Q000737:chemistry; D005910:Glioma / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D017895:Manganese Compounds / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry; D010087:Oxides / Q000737:chemistry; D011859:Radiography
chemical_list: D003287:Contrast Media; D017895:Manganese Compounds; D010087:Oxides; C027424:manganese oxide; D005492:Folic Acid
keywords: folic acid (FA); magnetic resonance imaging (MRI); manganese oxide nanoparticles (MnO NPs); tiny brain glioma