title: In vitro investigation of methylene blue-bearing, electrostatically assembled aptamer-silica nanocomposites as potential photodynamic therapeutics.
abstract: Photodynamic therapy, that is, excitation of a photosensitizer with light to generate reactive oxygen species such as singlet oxygen, has emerged as a noninvasive technique for cancer theranostics. However, the clinical use of many photosensitizers is impeded by their hydrophobicity, the nonspecific damage they cause to normal tissues, and their susceptibility to environmental degradation. In this study, we developed a simple electrostatic adsorption strategy to fabricate aptamer-silica nanocomposites by sequentially functionalizing nanocomposites with the cell surface-associated mucin 1 aptamer for tumor targeting and a hydrophilic photosensitizer, methylene blue, for photodynamic therapy applications. We investigated the relationship between the biophysical properties and cellular uptake of such nanocomposites to improve their formulation. Effective generation of singlet oxygen was achieved with a low photosensitizer dosage (0.5 μM) and a short, low-power irradiation (1 min, 10 mW/cm(2)). With the current strategy, the efficiency of photodynamic therapy was determined by the cellular uptake of nanocomposites and the targeting molecules used.
authors.affiliation: Department of Applied Chemistry, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: Tian-Shyng
authors.initials: TS
authors.lastname: Ding
authors.affiliation: Department of Applied Chemistry, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: Xin-Chun
authors.initials: XC
authors.lastname: Huang
authors.affiliation: Department of Applied Chemistry, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
authors.forename: Yun-Ling
authors.initials: YL
authors.lastname: Luo
authors.affiliation: Department of Applied Chemistry, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan; Institute of Molecular Science, National Chiao-Tung University, No. 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan. Electronic address: hyhsu99@nctu.edu.tw.
authors.forename: Hsin-Yun
authors.initials: HY
authors.lastname: Hsu
mesh_terms: D000327:Adsorption; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D016503:Drug Delivery Systems; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008751:Methylene Blue / Q000737:chemistry*; D018396:Mucin-1 / Q000737:chemistry; D053761:Nanocomposites / Q000737:chemistry*; D009369:Neoplasms / Q000628:therapy; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000008:administration & dosage / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D026082:Singlet Oxygen; D055672:Static Electricity
chemical_list: D018396:Mucin-1; D017319:Photosensitizing Agents; D026082:Singlet Oxygen; D012822:Silicon Dioxide; D008751:Methylene Blue
keywords: Aptamer–silica nanocomposite; Electrostatic assembly; Methylene blue; Photodynamic therapy; Singlet oxygen