title: Enhanced photodynamic therapy efficacy of methylene blue-loaded calcium phosphate nanoparticles.
abstract: Although methylene blue (MB) is the most inexpensive photosensitizer with promising applications in the photodynamic therapy (PDT) for its high quantum yield of singlet oxygen generation, the clinical use of MB has been limited by its rapid enzymatic reduction in the biological environment. To enhance PDT efficacy of MB by preventing the enzymatic reduction, we have developed a new mineralization method to produce highly biocompatible MB-loaded calcium phosphate (CaP-MB) nanoparticles in the presence of polymer templates. The resulting CaP-MB nanoparticles exhibited spherical shape with a size of under 50 nm. Fourier transform infrared (FT-IR) and zeta-potential analyses confirmed the insertion of MB into the CaP-MB nanoparticles. The encapsulation of MB in CaP nanoparticles could effectively protect MB from the enzymatic reduction. In addition, the CaP-MB nanoparticles exhibited a good biocompatibility in the dark condition and significantly enhanced PDT efficacy due to apoptotic cell death against human breast cancer cells as compared with free MB, implying that CaP-MB nanoparticle system might be potentially applicable in PDT.
authors: Department of Biomedical Engineering, Catholic University of Daegu, Gyeongsan 712-702, Republic of Korea.
authors: Da-Young
authors: DY
authors: Seong
authors: Department of Biomedical Engineering, Catholic University of Daegu, Gyeongsan 712-702, Republic of Korea. Electronic address: yjkim@cu.ac.kr.
authors: Young-Jin
authors: YJ
authors: Kim
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D002130:Calcium Phosphates; D018360:Crystallography, X-Ray; D006801:Humans; D061986:MCF-7 Cells / Q000187:drug effects; D008751:Methylene Blue / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D053758:Nanoparticles / Q000737:chemistry; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000494:pharmacology*; D026082:Singlet Oxygen / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D002130:Calcium Phosphates; D017319:Photosensitizing Agents; D026082:Singlet Oxygen; C020243:calcium phosphate; D008751:Methylene Blue