title: Efficient intracellular delivery of camptothecin by silica/titania hollow nanoparticles.
abstract: Silica/titania hollow nanoparticles (HNPs) with 50 nm were fabricated by using the dissolution and redeposition method and modified with anti-[human epidermal growth factor receptor 2] monoclonal antibody (herceptin), and their application as camptothecin (CPT) delivery agents to human breast cancer SK-BR-3 cells was investigated. Although the diameter of herceptin-modified HNPs (HER-HNP) is smaller than that of other reported mesoporous silica nanoparticles, the extensive hollow cavity of HNPs (ca. 30 nm) allowed the loading of a large amount of CPT. CPT-loaded HER-HNP (HER-HNP-CPT) did not release CPT in phosphate-buffered saline over a period of 24 h, however, HER-HNP-CPT in a hydrophobic solvent released its entire load of CPT. In addition, HER-HNPs were efficiently internalized owing to their herceptin conjugation and optimized size. To evaluate in vitro antitumor efficacy, apoptosis/necrosis and viability of HER-HNP-CPT-treated cells were investigated. When the cells were treated with HER-HNP-CPT for 30 min, a few apoptotic cells were observed. After 24 h, the viability of HER-HNP-CPT-treated SK-BR-3 decreased to 60 %, which revealed highly efficient chemotherapy. However, CPT loaded into HNP or HER-HNP had no significant effects on the viability of macrophages. Judging from these data, HER-HNPs are very suitable for application in anticancer therapy. A HER-HNP-CPT drug delivery system offers a new direction for a hydrophobic anticancer drug carrier and can be expanded to practical applications with further studies.
authors.affiliation: World Class University (WCU) program of Chemical Convergence for Energy & Environment (C2E2), School of Chemical and Biological Engineering, College of Engineering, Seoul National University, Daehak-dong, Seoul 151-747, Korea.
authors.forename: Chanhoi
authors.initials: C
authors.lastname: Kim
authors.forename: Sojin
authors.initials: S
authors.lastname: Kim
authors.forename: Wan-Kyu
authors.initials: WK
authors.lastname: Oh
authors.forename: Moonjung
authors.initials: M
authors.lastname: Choi
authors.forename: Jyongsik
authors.initials: J
authors.lastname: Jang
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000737:chemistry* / Q000493:pharmacokinetics; D002166:Camptothecin / Q000008:administration & dosage* / Q000737:chemistry* / Q000493:pharmacokinetics; D045744:Cell Line, Tumor; D004337:Drug Carriers / Q000737:chemistry*; D016503:Drug Delivery Systems / Q000379:methods*; D066246:ErbB Receptors / Q000737:chemistry*; D005260:Female; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D012822:Silicon Dioxide / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D000970:Antineoplastic Agents; D004337:Drug Carriers; C009495:titanium dioxide; D012822:Silicon Dioxide; D014025:Titanium; D066246:ErbB Receptors; D002166:Camptothecin