We investigate the interaction of lablets with other objects of comparable size that can be artificial (vesicles, microcapsules) or natural (cells, microorganisms).
The focus is on the interaction between electronics and chemistry while making use of the distributed nature of the lablets and their ability to participate in local (as opposed to bulk) chemical reactions.
Using a drop-on-demand inkjet fabrication process, we have prepared hydrogel microcapsules with immobilized magnetic nanoparticles, liposomes that carry a chemical payload, and enzymes that catalyze biochemical reactions.
The release of the chemical payload and the subsequent enzymatic reaction can be started, stopped and re-started “on demand” using radiofrequency (RF) signals. The concentration of the produced active substance can then be followed by spectrophotometric measurements. Complex spatio-temporal patterns can emerge when coupling the release and reaction kinetics with the movement, adhesion, and docking of the participating microcapsules and lablets.
Our work on the RF control of diffusion from hollow mesoporous SiO2 microparticles has recently been featured on the front cover of the Chemical Engineering Journal (Vol. 232, October 2013).
References:
[1] Kovačík P., Singh M., Štěpánek F., “Remote control of diffusion from magnetic hollow silica microspheres”, Chem. Eng. J. 232, 591-598 (2013)
[2] Hanuš J., Ullrich M., Dohnal J., Singh M., Štěpánek F., “Remotely controlled diffusion from magnetic liposome microgels”, Langmuir 29, 4381-4387 (2013)
[3] Ullrich M., Hanuš J., Dohnal J., Štěpánek F., “Encapsulation stability and temperature-dependent release kinetics from hydrogel-immobilised liposomes”, J. Coll. Interf. Sci. 394, 380-385 (2013)
[4] Čejková J., Haufová P., Gorný D., Hanuš J., Štěpánek F., “Biologically triggered liberation of sub-micron particles from alginate microcapsules”, J. Mater. Chem. B 1, 5456-5461 (2013)
[5] Tokárová V., Kašpar O., Knejzlík Z., Ulbrich P., Štěpánek F., “Development of spray-dried chitosan microcarriers for nanoparticle delivery”, Powder Technol. 235, 797-805 (2013)