title: Anti-inflammatory and anti-bacterial activity, and cytotoxicity of halloysite surfaces.
abstract: Halloysite is a naturally-occurring nanomaterial occurring in the thousands of tons and that serves as biomaterial, with applications in the areas of biotechnology, pharmaceutical, and medical research. This study reports on the anti-inflammatory, cytotoxic, and anti-oxidant activity of halloysite Jarrahdale (collected at ∼ 45 km SE of Perth, Western Australia; JA), Dragon Mine (provided by Natural Nano Inc., Rochester, New York; NA), and Kalgoorie Archean (collected at Siberia, ∼ 85km NW of Kalgoorlie, West Australia; PA). Prior to biological testing, halloysites were characterized by 27Al and 29Si Nuclear Magnetic Resonance Spectroscopy, the anti-inflammatory activity was determined by (a) the mouse ear edema method, using 12-o-tetradecanoylphorbol-13-acetate (TPA) as anti-inflammatory agent; and (b) the myeloperoxidase enzymatic activity method (MPO). Cell viability was determined using the MTT method. Sample characterization by NMR method showed similar symmetry and atomic environments, with no evidence of distortion(s) due to shiftings in atomic ordering or electron density. The anti-inflammatory activity followed the order: PA>JA>NA, and remained invariant with time. Prolonged anti-inflammatory activity related inversely to surface area and lumen space. The low extent of infiltration at shorter reaction times confirmed a limiting number of active surface sites. EPR intensity signals followed the order: JA>NA>PA. The poor stabilization of RO species in PA suspensions was explained by tube alignment provoking occlusion, thus limiting transfer of H(+) or e(-) from-and-to the surface, and decreases in acidity associated to Al(oct). Cell viability (%) varied from one surface to the other, PA(92.3 ± 6.0), JA(84.9 ± 7.8), and NA(78.0 ± 5.6), but related directly to SBET values.
authors.affiliation: Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana Unidad Cuajimalpa, Mexico; Earth Sciences Division, Lawrence Berkeley National Laboratory, United States. Electronic address: jcervini@correo.cua.uam.mx.
authors.forename: Javiera
authors.initials: J
authors.lastname: Cervini-Silva
authors.affiliation: Laboratorio de Pruebas Biológicas, Instituto de Química, Universidad Nacional Autónoma de México, Mexico.
authors.forename: Antonio
authors.initials: A
authors.lastname: Nieto-Camacho
authors.affiliation: Dirección de Investigación y Posgrado, Instituto Mexicano del Petróleo, Mexico.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Palacios
authors.affiliation: Dirección de Investigación y Posgrado, Instituto Mexicano del Petróleo, Mexico.
authors.forename: José Ascención
authors.initials: JA
authors.lastname: Montoya
authors.affiliation: Laboratorio de Pruebas Biológicas, Instituto de Química, Universidad Nacional Autónoma de México, Mexico.
authors.forename: Virginia
authors.initials: V
authors.lastname: Gómez-Vidales
authors.affiliation: Laboratorio de Pruebas Biológicas, Instituto de Química, Universidad Nacional Autónoma de México, Mexico.
authors.forename: María Teresa
authors.initials: MT
authors.lastname: Ramírez-Apán
mesh_terms: D000538:Aluminum Silicates / Q000633:toxicity*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D016923:Cell Death / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D000077215:Clay; D004583:Electrons; D007474:Ion Exchange; D017737:Macrophages, Peritoneal / Q000166:cytology / Q000187:drug effects; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D009195:Peroxidase / Q000378:metabolism; D020349:Surface Plasmon Resonance; D013499:Surface Properties; D013755:Tetradecanoylphorbol Acetate
chemical_list: D000538:Aluminum Silicates; D000900:Anti-Bacterial Agents; D000893:Anti-Inflammatory Agents; D009195:Peroxidase; D013755:Tetradecanoylphorbol Acetate; D000077215:Clay
keywords: Surface morphology; Time-dependent infiltration