title: Preliminary study of the anticancer applications of mesoporous materials functionalized with the natural product betulinic acid.
abstract: Dehydrated MCM-41 (S1) was functionalized under nitrogen with 3-chloropropyltriethoxysilane (CPTS) and 3-aminopropyltriethoxysilane (APTS) by grafting in toluene at 80 °C over 48 h to give the corresponding materials S2 and S3, respectively. Subsequently, S2 and S3 were suspended in methanol and reacted in a nitrogen atmosphere with betulinic acid (BA) for 48 h at 65 °C (in the presence of the triethylamine of S2) to give the BA-functionalized materials S4 and S5. All materials studied were characterized by powder X-ray diffraction, X-ray fluorescence, nitrogen gas sorption, multinuclear MAS NMR spectroscopy, thermogravimetry, UV spectroscopy, IR, SEM, and TEM. To study the release of BA, S4 and S5 were suspended in solutions simulating various body pH conditions (pH 7.4, 5.5, and 3.0). Results of the quantification of BA release by HPLC for S4 show a pH-dependent and very slow BA release following a logarithmic tendency, while S5 behaves differently, also pH-dependent but, in this case, fast release of BA which requires only days for total release of the therapeutic compound. In addition, the cytotoxic activity of all synthesized materials against various cancer cell lines was studied. The results show the absence of an antiproliferative effect on the surfaces without BA S1-S3, while an antiproliferative effect was observed with S4 and S5 and was attributed to the release of BA in the medium.
authors.affiliation: Departamento de Química Inorgánica y Analítica, E.S.C.E.T. Universidad Rey Juan Carlos, 28933 Móstoles, Madrid, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Sánchez-Muñoz
authors.forename: Santiago
authors.initials: S
authors.lastname: Gómez-Ruiz
authors.forename: Damián
authors.initials: D
authors.lastname: Pérez-Quintanilla
authors.forename: Sonia
authors.initials: S
authors.lastname: Morante-Zarcero
authors.forename: Isabel
authors.initials: I
authors.lastname: Sierra
authors.forename: Sanjiv
authors.initials: S
authors.lastname: Prashar
authors.forename: Reinhard
authors.initials: R
authors.lastname: Paschke
authors.forename: Goran N
authors.initials: GN
authors.lastname: Kaluđerović
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology; D045744:Cell Line, Tumor; D016503:Drug Delivery Systems; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D046529:Microscopy, Electron, Transmission; D009584:Nitrogen / Q000737:chemistry; D053978:Pentacyclic Triterpenes; D016062:Porosity; D011437:Propylamines; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D013818:Thermogravimetry; D014315:Triterpenes / Q000737:chemistry* / Q000494:pharmacology*; D014961:X-Ray Diffraction; D000094062:Betulinic Acid
chemical_list: D000970:Antineoplastic Agents; C509968:MCM-41; D053978:Pentacyclic Triterpenes; D011437:Propylamines; D012821:Silanes; D014315:Triterpenes; D012822:Silicon Dioxide; C477625:amino-propyl-triethoxysilane; D009584:Nitrogen; D000094062:Betulinic Acid