Levitation and movement of tripalmitin-based cationic lipospheres on a dielectrophoresis-based lab-on-a-chip device

Dielectrophoresis (DEP) is a very valuable approach for designing and developing laboratory-on-a-chip (lab-on-a-chip) devices that are able to manipulate microparticles and cells. Lab-on-a-chip technology will enable laboratory testing to move from laboratories using complex equipment to nonlaboratory settings. We used a lab-on-a-chip device, the SmartSlide, which carries 193 parallel electrodes and generates up to 50 cylinder-shaped DEP cages able to entrap microparticles and cells within DEP cages and move them along the chip. For lab-on-a-chip technology, the characterization of microparticles exhibiting a differential ability to be DEP-caged, levitated, and moved is important for the development of both diagnostic and therapeutic protocols. We determined whether the SmartSlide could be used to levitate and move tripalmitin-based lipospheres carrying increasing concentrations of dihexadecyl dimethyl ammonium bromide (DHDAB) as a cationic surfactant. The data obtained with this DEP-based platform showed that DEP caging, levitation, and movement of the cationic lipospheres depended on the percentage of DHDAB. Tripalmitin lipospheres containing 6% DHDAB could be DEP-caged and manipulated. On the contrary, lipospheres containing 12% DHDAB did not exhibit an efficient ability to be DEP-caged and moved throughout the chip. To our knowledge, this is the first report on the possible use of a DEP-based lab-on-a-chip device for guided manipulation of lipospheres. This information might be of interest in the fields of drug discovery, delivery, and diagnosis. (c) 2008 Wiley Periodicals, Inc.