Surface biofunctionalization and production of miniaturized sensor structures using aerosol printing technologies

Abstract

The work described in this paper demonstrates that very small protein and DNA structures can be applied to various substrates without denaturation using aerosol printing technology. This technology allows high-resolution deposition of various nanoscaled metal and biological suspensions. Before printing, metal and biological suspensions were formulated and then nebulized to form an aerosol which is aerodynamically focused on the printing module of the system in order to achieve precise structuring of the nanoscale material on a substrate. In this way, it is possible to focus the aerosol stream at a distance of about 5 mm from the printhead to the surface. This technology is useful for printing fluorescence-marked proteins and printing enzymes without affecting their biological activity. Furthermore, higher molecular weight DNA can be printed without shearing. The advantages, such as printing on complex, non-planar 3D structured surfaces, and disadvantages of the aerosol printing technology are also discussed and are compared with other printing technologies. In addition, miniaturized sensor structures with line thicknesses in the range of a few micrometers are fabricated by applying a silver sensor structure to glass. After sintering using an integrated laser or in an oven process, electrical conductivity is achieved within the sensor structure. Finally, we printed BSA in small micrometre-sized areas within the sensor structure using the same deposition system. The aerosol printing technology combined with material development offers great advantages for future-oriented applications involving biological surface functionalization on small areas. This is important for innovative biomedical micro-device development and for production solutions which bridge the disciplines of biology and electronics.

Composition-dependent sintering behaviour of chemically synthesised CuNi nanoparticles and their application in aerosol printing for preparation of conductive microstructures

“…The basic functional principles of Aerosol Jet® printing are discussed in more detail in refs. [34][35][36]. In order to deposit the CuNi nanoparticles, the dispersions were kept at room temperature, and the aerosol was generated by pneumatic nebulizer.…”

“…inks), whereby printed layers for functional structures, i.e. conductive paths [32], vapour sensors [33], biosensors [34], thermopiles or strain gauges [35,36], can be easily fabricated. Nowadays mainly commercial silver dispersions are used for the preparation of such functional structures.…”

Additive Manufacturing Technologies Compared: Morphology of Deposits of Silver Ink Using Inkjet and Aerosol Jet Printing

“…14,24 However, in comparison to IJP the number of scientific publications is much less. Comparisons of the two technologies concerning the characteristics of their deposits are underrepresented in the literature.…”

Fabrication of soft gold microelectrode arrays as probes for scanning electrochemical microscopy

“…Eight nanoparticle gold ink lines of approximately 6 cm length and with a midpoint-midpoint distance of 500 lm were printed on 125 lm thick polyimide films using an Aerosol Jet Ò printer work station (Optomec Inc., Singer, Albuquerque, USA) similar to a previous report [42]. After printing, the gold ink tracks were sintered in an oven under atmosphere for 2 h at 400°C in order to eliminate ink additives, which are used for stabilization of Au nanoparticles in the ink, and to achieve electrical conductivity.…”

“…Post-treatment of the printed areas is performed by heating in an oven or (especially for low temperature substrates) by a laser system that is integrated in the printing device which generates a continuous laser beam of the same dimensions as the printed track width. Applications of Aerosol Jet Ò printing technology have been found for the fabrication of cell arrays and printing of biomolecules or metal inks for sensing purposes [42]. Front side metallization of silicon solar cells with 5 cm  5 cm silver grids as a first layer of a 2-layer contact was also reported [43].…”