Thermo-Liposomes Controlling Enzymes: Towards a Biomimetic Synthesis of Materials

BELLINO, M.G.; MUNICOY, SOFÍA

San Martin

Workshop; 1st Argentine-German Workshop on Nanotechnology and Nanobiosensors; 2017

INTI

The ability to regulate enzyme activity in response to remotecontrol is critical to many biotechnological applications. In aseparate but related thread, the fabrication of bioinspirednanometer-sized materials has gained considerable attentionbecause of their potential uses in both biomaterial research andthe development of dynamic nanomaterials as well asfundamental new insights on biomineralization. In particular, thebio-inspired synthesis of materials is one of the most promisingmethods to achieve the successful conformation of hybridmaterials from the synthesis of inorganic materials by naturalsystems. At the same time, the homogenous precipitation has alsoproved to be a versatile method for generating a wide variety offine particles with well-defined morphologies.In relation to the line of biomineralization, the catalyticdecomposition of urea by the enzyme urease has been used toinduce the precipitation of calcium carbonate. On the other hand,lipid vesicles (liposomes) have been widely used to encapsulate awide variety of enzymes. However, the development of systemsin which the enzymatic activity is controlled by the liposomessurrounding the enzymes has not yet been explored.In this work, combining the previous concepts, we designed anassembly to actuate the reactivity of ureases through theirencapsulation in thermo-liposomes, by changing the membranespermeability by means of temperature control [1]. Takingadvantage of the capabilities of this novel enzymatic controlsystem, liposome/urease assemblies were used as biomimeticreactors for the construction of silicon dioxide nanocapsules,from a mesoporous sacrificial film that was dissolved andreprecipitated around the liposomes forming a three-dimensionalcoating, and of various gadolinium carbonate nanostructures,from a Gd+3 salt. This was achieved from a controlledprecipitation of the different inorganic compounds on the surfaceof the vesicles. In this sense, as proof of concept, it wasdemonstrated that biological nanoreactors based on liposomesencapsulating enzymes can be used as artificialmicroenvironments for the control of enzymatic activity. What ismore, the method is extrapolable to the encapsulation of differentenzymes with diverse functionalities and easily scalable, reasonwhy it may be feasible to develop responsive enzymenanoreactorsfor a broad range of biotechnology applications. Inaddition, the synergism between enzymatic activity andmembrane permeability can be used for the bioinspired synthesisof different complex structures.