03100naa a2200541 a 450000100080000000500110000800800410001902400360006010000180009624501610011426000090027552014350028465000130171965000190173265000110175165300250176265300200178765300280180765300200183565300240185565300340187965300280191365300410194165300390198265300220202165300240204365300220206765300420208965300160213165300170214765300240216465300190218865300200220765300230222765300230225065300380227365300170231165300270232865300100235570000170236570000160238270000220239870000150242070000210243570000240245670000170248077300610249720912502019-11-07       2018    bl uuuu     u00u1 u    #d7 a10.1038/s41598-018-23921-22DOI1 aMATTOS, B. D.  aControlled biocide release from hierarchically-structured biogenic silicabsurface chemistry to tune release rate and responsiveness.h[electronic resource]  c2018  aBiocides are essential for crop protection, packaging and several other biosystem applications. Therein, properties such as tailored and controlled release are paramount in the development of sustainable biocide delivery systems. We explore the self-similar nano-organized architecture of biogenic silica particles to achieve high biocide payload. The high surface area accessibility of the carrier allowed us to develop an efcient, low energy loading strategy, reaching signifcant dynamic loadings of up to 100mg·g?1. The release rate and responsiveness were tuned by manipulating the interfaces, using either the native hydroxyl surfaces of the carrier or systems modifed with amines or carboxylic acids in high density. We thoroughly evaluated the impact of the carrier-biocide interactions on the release rate as a function of pH, ionic strength and temperature. The amine and carboxyl functionalization strategy led to three-fold decrease in the release rate, while higher responsiveness against important agro-industrial variables. Key to our discoveries, nanostructuring thymol in the biogenic silica endowed systems with controlled, responsive release promoting remarkable, high and localized biocidal activity. The interfacial factors afecting related delivery were elucidated for an increased and localized biocidal activity, bringing a new light for the development of controlled release systems from porous materials.  aBiocides  aNanotechnology  aThymol  aAtividade biológica  aBiocida natural  aBiocide delivery system  aBiogenic silica  aBiological activity  aChemical surface modification  aFractal supra structure  aFuncionalização de nanopartículas  aFunctionalization of nanoparticles  aLiberação lenta  aMaterial nanoporoso  aMesoporous silica  aModificação química de superfície  aNanobiocida  aNanobiocides  aNanoporous material  aNanotecnologia  aNatural biocide  aSílica biogênica  aSílica mesoporosa  aSistema de liberação de biocida  aSlow release  aSupraestrutura fractal  aTimol1 aTARDY, B. L.1 aPEZHMAN, M.1 aKÄMÄRÄINEN, T.1 aLINDER, M.1 aSCHREINER, W. H.1 aMAGALHAES, W. L. E.1 aROJAS, O. J.  tScientific Reportsgv. 8, Article 5555, Apr. 2018. 11 p.