title: Phase and size controllable synthesis of NaYbF4 nanocrystals in oleic acid/ionic liquid two-phase system for targeted fluorescent imaging of gastric cancer.
abstract: Upconversion nanocrystals with small size and strong fluorescent signals own great potential in applications such as biomolecule-labeling, in vivo tracking and molecular imaging. Herein we reported that NaYbF4: 25%Gd, 2%Tm upconversion nanocrystals with small size and strong fluorescent signals were controllably synthesized by oleic acid (OA)/ ionic liquid (IL) two-phase system for targeted fluorescent imaging of gastric cancer in vivo. The optimal synthesis condition of NaYbF4: 25%Gd, 2%Tm upconversion nanocrystals by OA/IL two-phase system was established, adding more metal ion such as Na(+) ion could facilitate the size control and crystal-phase transition, more importantly, markedly enhancing fluorescent intensity of beta-phase nanocrystals compared with traditional methods. Alpha-phase NaYbF4, 2%Tm upconversion nanocrystals with less than 10nm in diameter and beta-phase NaYbF4: 25%Gd, 2%Tm upconversion nanocrystals with 30 nm or so in diameter and strong fluorescent signals were obtained, these synthesized nanocrystals exhibited very low cytotoxicity. Folic acid-conjugated silica-modified beta-phase NaYbF4: 25%Gd, 2%Tm upconversion nanocrystals were prepared, could actively target gastric cancer tissues implanted into nude mice in vivo, and realized targeted fluorescent imaging. Folic acid-conjugated silica-modified NaYbF4: 25%Gd, 2%Tm upconversion nanocrystals show great potential in applications such as targeted near infared radiation fluorescent imaging, magnetic resonance imaging and targeted therapy of gastric cancer in the near future.
authors.affiliation: Department of Bio-Nano Science and Engineering, Key Laboratory for Thin Film and Microfabrication of Ministry of Education, Institute of Micro-Nano Science and Technology, Shanghai Jiao Tong University, 800Dongchuan Road, Shanghai200240, PR China.
authors.forename: Liyuan
authors.initials: L
authors.lastname: Pan
authors.forename: Meng
authors.initials: M
authors.lastname: He
authors.forename: Jiebing
authors.initials: J
authors.lastname: Ma
authors.forename: Wei
authors.initials: W
authors.lastname: Tang
authors.forename: Guo
authors.initials: G
authors.lastname: Gao
authors.forename: Rong
authors.initials: R
authors.lastname: He
authors.forename: Haichuan
authors.initials: H
authors.lastname: Su
authors.forename: Daxiang
authors.initials: D
authors.lastname: Cui
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005459:Fluorides / Q000008:administration & dosage* / Q000138:chemical synthesis / Q000737:chemistry / Q000493:pharmacokinetics*; D052578:Ionic Liquids / Q000737:chemistry; D051379:Mice; D008819:Mice, Nude; D053758:Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D019301:Oleic Acid / Q000737:chemistry; D061848:Optical Imaging / Q000379:methods*; D017670:Sodium Compounds / Q000008:administration & dosage* / Q000138:chemical synthesis / Q000737:chemistry / Q000493:pharmacokinetics*; D013274:Stomach Neoplasms / Q000175:diagnosis* / Q000473:pathology; D015018:Ytterbium / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*
chemical_list: D052578:Ionic Liquids; D017670:Sodium Compounds; C102799:ytterbium fluoride; D019301:Oleic Acid; D015018:Ytterbium; D005459:Fluorides
keywords: 2%Tm upconversion nanocrystals; NaYbF4: 25%Gd; cytotoxicity.; fluorescent imaging; gastric cancer; synthesis; targeted imaging