Melatonin/nanoclay hybrids for skin delivery Borrego Sánchez, Ana María Viseras Iborra, César Antonio Hernández Laguna, Alfonso Sainz Díaz, Claro Ignacio Melatonin Molecular modeling Adsorption Clays Modified drug release Molecular dynamics This research was funded by the European COST Action CA17120 supported by the EU Framework Programme Horizon 2020, the funding support of the Spanish MINECO FIS2016-77692-C2 and PCIN2017-098 projects, and the P18-RT-3786 project with FEDER European contribution. Melatonin is a hormone used for treating several disorders. However, its oral administration is problematic due to the variable absorption and extensive first-pass metabolism. The topical application of this drug does not present these disadvantages and can be used for therapeutic and skin protection purposes. The adsorption and release of melatonin in the montmorillonite clay were investigated experimentally and theoretically. The drugclay interaction products were prepared and characterized, showing a modified and improved release of melatonin. The crystal structure and spectroscopic properties of the crystal of melatonin and melatonin-water-mineral materials were studied by molecular modeling, finding that the adsorption of this drug is energetically favourable, and the results were consistent with the experimental data. Ab initio molecular dynamics simulations with the metadynamics methodology showed the release of melatonin from the confined interlayer nanospace of montmorillonite to the liquid bulk water with a 20 kcal/mol free energy barrier. 2022-05-31T06:46:02Z 2022-05-31T06:46:02Z 2022-01-29 journal article Ana Borrego-Sánchez... [et al.]. Melatonin/nanoclay hybrids for skin delivery, Applied Clay Science, Volume 218, 2022, 106417, ISSN 0169-1317, [https://doi.org/10.1016/j.clay.2022.106417] http://hdl.handle.net/10481/75115 10.1016/j.clay.2022.106417 eng http://creativecommons.org/licenses/by-nc-nd/3.0/es/ open access Atribución-NoComercial-SinDerivadas 3.0 España Elsevier