First published 2 September 2013
Radiofrequency triggered enzymatic reaction inside hydrogel microparticles
Martin Ullrich, Petra Haufová, Mandeep Singh, František Štěpánek
Biochemical reactions in living organism usually take place inside cells. The characteristic feature of these reactions is their executability; the organism does not produce certain substances all the time, but only when they are needed. The reaction is usually triggered after receiving an extra- (or intra-) cellular signal. Stimuli-responsiveness is mostly possible because of compartmentalization of the cells. Reactants, enzymes and other factors are separated to different parts of cells by membranes forming organelles. Upon receiving a signal, the substances are selectively transported through the membranes and a reaction occurs.
In order to mimic that behaviour we present internally-structured cell-like micro-particles with a diameter around 50 µm. The particles are formed by an alginate gel, thermo-responsive liposomes form internal compartments filled by an encapsulated content. The particles also contain ferrofluid (Fe2O3 magnetic nanoparticles). High-frequency magnetic field causes heating of the particles hence release the content from thermo-sensitive liposomes into the gel body and then out of the particles (Hanuš, et al. 2013). Thermo-sensitive liposomes are characteristic by a change of bilayer structure at certain temperature.