BACKGROUND:  In the race for achieving miniaturization of useful machines and devices to the microscale and nanoscale, it would be useful to have a means of connecting components to build devices. One-off production of assemblies of components might be made using laser tweezers or microfluidics, yet it would be highly desirable to assemble millions or billions of copies of the same multicomponent device in solution in parallel at the same time. Heretofore, such massively parallel off-chip assembly processes have been only poorly controlled because the interactions have not been strongly dependent on the nature of the geometry and shape of the components.

INNOVATION:  Researchers at UCLA have developed a method to construct complex microstructures via mass fabrication techniques employing depletion attractions that depend on the shapes of particulate components. From a solution containing a mixture of particles with similar or different shapes, this method induces aggregation of targeted particles into larger structures. The method can induce aggregation of particles with similar shapes into ordered structures as well as binding particles of different shapes into pre-determined configurations. This facilitates the fabrication of multiparticle structures for applications in drug delivery and microscale assembly.

POTENTIAL APPLICATIONS 

• Particle separation and drug delivery for nanotechnology applications
• Massively parallel off-chip assembly of MEMS and other microstructures
• Mass production of active microscale delivery devices for drug delivery applications

ADVANTAGES

• Provides very specific targeting of particle interactions based on the particle shape
• Enables multiple-step fabrication schemes of microstructures
• Allows composite microstructures to be fabricated

Related Papers (Selected)

• Carlos J. Hernandez and Thomas G. Mason , "Colloidal Alphabet Soup: Monodisperse Dispersions of Shape-Designed LithoParticles," J. Phys. Chem. C, 111 (12), 4477-4480 (2007) [more]
• T. G. Mason, "Osmotically driven shape-dependent colloidal separations," Physical Review E, 66, 060402(R) (2002) [more]

Reference: UCLA Case No. 2007-405