|DPN can be employed for the direct generation of photonic structures as well as for the post functionalization of sensor devices fabricated by other methods. The high-precision positioning and the ability to write on three dimensional pre-strcutured surfaces opens up additional possibilities to functionalize devices fabricated by standard semiconductor industry processes. By combining the well established methods for device fabrication and the advantages of DPN on regard to materials and parallel writing of different inks, sensors with functionalization not achievable by standard lithography methods can be generated. One example ist the decoration of optical resonator structures with lipids by DPN (upper right). The lipid mixture added to the rims of the goblet structure serves as optical active material as well as specific binding site for target proteins. The so-functionalized goblet structures can then serve as sensors based on the shift in optical properties during protein binding. To enhance throughput and ease alignment procedures, it is also possible to use aligned stamping to apply lipid functionalization (middle left). Here, a stamp pad is first generated by multi-color polymer pen lithography (PPL) and subsequently stamped onto a goblet array. A combined fluorescence / bright field image of a functionalized array is shown on the middle right.
Another interesting material for use in electronical devices is graphene. We study the feasibility of using this material for writing of taylored membrane patches that can be utilitzed in graphene based sensor devices or to render graphene bio-compatible when interfacing to cells.
Resonator microgoblet structures get functionalized by DPN. The inset shows a SEM micrograph of one resonator structure.
A multiplexed stamp pad (generated by multi-color PPL) is aligned with an array of goblet structures for massively parallelized functionalization (left). Combined fluorescence and bright field images of a functionalized goblet array (right)
Writing of lipid membranes onto graphene. The inset shows a lipid structure written partly on graphene (left part) and silicon oxide (right part).
Large-Scale Parallel Surface Functionalization of Goblet-type Whispering Gallery Mode Microcavity Arrays for Biosensing Applications
U. Bog, F. Brinkmann, H. Kalt, C. Koos, T. Mappes, M. Hirtz, H. Fuchs, S. Köber
Small 10 (2014) 3863-3868, DOI:10.1002/smll.201400813
Multiplexed biomimetic lipid membranes on graphene by dip-pen nanolithography
M. Hirtz, A. Oikonomou, T. Georgiou, H. Fuchs, A. Vijayaraghavan
Nat. Commun. 4 (2013) 2591, DOI:10.1038/ncomms3591
On-chip microlasers for biomolecular detection via highly localized deposition of a multifunctional phospholipid ink
U. Bog, T. Laue, T. Grossmann, T. Beck, T. Wienhold, B. Richter, M. Hirtz, H. Fuchs, H. Kalt, T. Mappes
Lab Chip 13 (2013) 2701-2707, DOI:10.1039/C3LC50149C