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In the attempt of satisfying the quest for new antifouling products tailored for applications on Cultural Heritage, we have synthesized and characterized two different silica nanosystems. The first consists of core-shell nanocapsules and the second one of mesostructured nanoparticles. Both systems have been successfully loaded in situ with the commercial biocide 2-mercaptobenzothizole (MBT). The synthesis procedure and particles characterization measurements, as far as their dimensions and superficial properties, loading capability, and release rate in aqueous solution, are reported. We stress that both particles have the dimensions required to avoid undesired light scattering once dispersed on the artefact surface. Interestingly, the two nanoparticles have complementary properties, suggesting that combining them in a coating may have a higher potential for production of new generation active products. • Two different pore-templating surfactant strategy to obtained silica nanocontainers. • Design of a new silica nanosystem to control the release rate of biocide in antifouling coatings. • Successful encapsulation of 2-mercaptobenzothiazole into two nanosystems with complementary release properties. [ABSTRACT FROM AUTHOR]

• FTIR and Raman spectroscopy investigation of the MBT confinement into two different silica nanosystems. • Evaluation of the chemical interaction of the MBT biocide with silica nanosystems and cationic surfactant molecules. In the last years, significant research efforts have been devoted to the reduction of the environmental impact of biocides and to the improvement of their effectiveness over time against degradation of stone artifacts. This work reports the spectroscopic characterization of two silica nanosystems, with different geometry and structure, loaded with a biologically-active compound, the 2-mercaptobenzothiazole (MBT), for controlled antifouling release on the surface of outdoor stone artefacts. We have combined FT-IR spectroscopy in ATR mode and Raman spectroscopy to investigate the biocide loading mechanism in both nanosystems from the physical and chemical point of view. These techniques demonstrate that the geometry of confinement influences the loading of the nanoparticles and their interaction with the confining medium, with possible consequences in the biocide release rate. Moreover, we have seen that the biocide interacts with the surfactant (cetrimonium bromide, CTAB) and tends to dimerize. [ABSTRACT FROM AUTHOR]