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The production of human recombinant proteins to be used for therapeutic or nutritional purposes must focus on obtaining a molecule that is as close as possible to the native human protein. This biotechnological tool has been documented in various studies published in recent decades, with lactoferrin being one of those that has generated the most interest, being a promising option for recombinant technology. However, stability studies including thermodynamic parameters have not been reported for recombinant lactoferrin (Lf). The objective of this work was to obtain the human recombinant protein using the yeast Komagataella phaffii to study structural changes modifying pH and temperature using circular dichroism spectroscopy (CD). Thermodynamic parameters such as ΔH, ΔS and Tm were calculated and compared with commercial human lactoferrin. We propose the potential use of CD and thermodynamic parameters as a criterion in the production of recombinant proteins to be used in the production of specialized recombinant proteins. [ABSTRACT FROM AUTHOR]

[Display omitted] • Relationship between synthesis pH and rugosity of the coatings has been assessed. • The alkaline pH affects the synthesis in situ of the TiO 2 nanoparticles. • The use of HMDS improve the self-cleaning properties of the SiO 2 -TiO 2 coating. • The use of TiO 2 nanoparticles changes from hydrophobic state to a hydrophilic state. The SiO 2 -TiO 2 composite has been studied through several techniques obtaining different morphologies and specific properties of SiO 2 and TiO 2. Nevertheless, the modification of the synthesis pH and the addition of different hydrophobic agents, such as hexamethyldisilazane (HDMS) and polydimethylsiloxane (PDMS), have not been thoroughly studied and reported. This work assessed the presence of two different hydrophobic agents and the pH modification. The SiO 2 -TiO 2 coating was synthesized through two vias, basic and acid environment, employing the sol–gel method coupled to the sonochemistry technique. Moreover, the change of pH and use of P25 TiO 2 nanoparticles and TiO 2 -synthesized nanoparticles allows establishing a relationship with the self-cleaning properties. The samples of SiO 2 -TiO 2 composite were analyzed by AFM, indicating a variation in surface morphology and roughness concerning the PDMS and HMDS hydrophobic agent. ATR-FTIR analysis exhibit changes in intensity in vibrations of the Si-O, PDMS, and HMDS bonds. Raman spectroscopy results show the vibrations of the anatase and rutile phases of the TiO 2 and the corresponding vibrations to the hydrophobic agents. The evaluation of self-cleaning properties demonstrated changes from the hydrophobic state to the hydrophilic state due to the addition of the nanoparticles of TiO 2 to the SiO 2. The photocatalytic activity was modified and improved in the HMDS-1 coating due to the hydrophobic agent and type of nanoparticles. To compare the effect of the pH in the PDMS and HMDS coatings, carried out with cyclic voltammograms and Differential Capacitance spectra. Finally, the storage time of SiO 2 -TiO 2 coating was improved using the HMDS hydrophobic agent. [ABSTRACT FROM AUTHOR]