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An electrically induced bottom-up process was introduced for the fabrication of multifunctional nanostructures of polymers. Without requiring complicated photolithography or printing techniques, the fabrication process first produced a conducting template by colloidal lithography to create an interconnected conduction pathway. By supplying an electrical charge to the conducting network, the conducting areas were enabled with a highly energized surface that generally deactivated the adsorbed reactive species and inhibited the vapor deposition of poly-p-xylylene polymers. However, the template allowed the deposition of ordered poly-p-xylylene nanostructures only on the confined and negative areas of the conducting template, in a relatively large centimeter-scale production. The wide selection of functionality and multifunctional capability of poly-p-xylylenes naturally rendered the synergistic and orthogonal chemical reactivity of the resulting nanostructures. With only a few steps, the construction of a nanometer topology with the functionalization of multiple chemical conducts can be achieved, and the selected deposition process represents a state-of-the-art nanostructure fabrication in a simple and versatile approach from the bottom up. [ABSTRACT FROM AUTHOR]

In addition to the widely adopted method of controlling cell attachment for cell patterning, pattern formation via cell proliferation and differentiation is demonstrated using precisely defined interface chemistry and spatial topology. The interface platform is created using a maleimide-functionalized parylene coating (maleimide-PPX) that provides two routes for controlled conjugation accessibility, including the maleimide-thiol coupling reaction and the thiol-ene click reaction, with a high reaction specificity under mild conditions. The coating technology is a prime tool for the immobilization of sensitive molecules, such as growth factor proteins. Conjugation of fibroblast growth factor 2 (FGF-2) and bone morphogenetic protein (BMP-2) was performed on the coating surface by elegantly manipulating the reaction routes, and confining the conjugation reaction to selected areas was accomplished using microcontact printing (μCP) and/or UV irradiation photopatterning. The modified interface provides chemically and topologically defined signals that are recognized by cultured murine preosteoblast cells for proliferation (by FGF-2) and osteogenesis (by BMP-2) activities in specific locations. The reported technique additionally enabled synergistic pattern formation for both osteogenesis and proliferation activities on the same interface, which is difficult to perform using conventional cell attachment patterns. Because of the versatility of the coating, which can be applied to a wide range of materials and on curved and complex devices, the proposed technology is extendable to other prospective biomaterial designs and material interface modifications. [ABSTRACT FROM AUTHOR]

Aninnovative intraocular lens (IOL) device was fabricated basedon a chemical vapor deposition encapsulation process using functionalizedpoly-p-xylylenes. The advanced IOL device providesnoncompromised design parameters for both its optical and biologicalproperties. As an excellent optical device, it provides a high refractiveindex and a tunable effective focal length that is realized by manipulatingthe wetting properties of the encapsulated liquids; the device alsooffers protection from UV radiation. As a key medical device, it exhibitsexcellent biocompatibility and reduced postoperative calcificationthrough the intrinsic properties of poly-p-xylylenes.In addition, these synergic functions are provided with precise surfacechemistry for location to a guided attachment or repellent propertiesfor eye epithelial cells, which is important in preventing device-associatedcomplications. [ABSTRACT FROM AUTHOR]