Ponente
Descripción
Clays and clay minerals are widely used due to their cationic exchange and adsorptive properties, with high ability to accommodate pharmaceutical ingredients [1-4]. L-ascorbic acid (LAA), commonly known as vitamin C, is an excellent and recognized antioxidant molecule used in the pharmaceutical and cosmetic formulations. Several strategies have been developed in order to preserve its chemical stability [4, 5], connected with its antioxidant power, but there is little research regarding the employ of natural clays as LAA host. A safe bentonite (Bent)‒which was verified by in vivo ophthalmic irritability and acute dermal toxicity assays‒was used as carrier of LAA. The hybrid complex between LAA and clay may constitute an excellent alternative, since the molecule integrity does not seem be affected, at least from the point of view of its antioxidant capacity [6]. The Bent/LAA hybrid was prepared and characterized through of ultraviolet (UV) spectroscopy, X-ray diffraction (XRD), infrared (IR) spectroscopy, thermogravimetric analysis (TG/DTG) and zeta potential measurements. Photostability and antioxidant capacity tests were also performed. The LAA incorporation into Bent clay was demonstrated, as well as the drug stability due to Bent photoprotective effect onto LAA molecule. Moreover, the antioxidant capacity of the drug in the Bent/LAA composite was confirmed.
References
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[2] Valdés, L., Hernández, D., de Ménorval, L. C., Pérez, I., Altshuler, E., Fossum, J. O., Rivera, A. (2016). Incorporation of tramadol drug into Li-Fuorohectorite clay: A preliminary study of a medical nanofuid. The European Physical Journal Special Topics 225, 767-771.
[3] Hernández, D., Lazo, L., Valdés, L., de Ménorval, L. C., Rozynek, Z., Rivera, A. (2018). Synthetic clay mineral as nanocarrier of sulfamethoxazole and trimethoprim. Applied Clay Science 161, 395-403.
[4] da Rocha, M. C., Galdino, T., Trigueiro, P., Honorio, L. M. C., de Melo Barbosa, R., Carrasco, S. M., Silva-Filho, E. C., Osajima, J. A., Viseras, C. (2022). Clays as Vehicles for Drug Photostability. Pharmaceutics 14, 796.
[5] Caritá, A. C., Fonseca-Santos, B., Shultz, J. D., Michniak-Kohn, B., Chorilli, M., Leonardi, G. R. (2020). Vitamin C: One compound, several uses. Advances for delivery, efficiency and stability. Nanomedicine: Nanotechnology, Biology and Medicine 24, 102117.
[6] Hernández, D., Montalvo, A., Pérez, I., Charnay, C., Sánchez-Espejo, R., Cerezo, P., Viseras, C., Riela, S., Cinà, G., Rivera, A. (2023). Antioxidant efficacy and “in vivo” safety of a bentonite/vitamin C hybrid. To be submitted to Pharmaceutics.
