Macroscopic arrays of cell-based sensors immobilized on solid and flexible substrates in silk sandwich stacks using ink-jet printing are reported.  Engineered bacterial cells (E.coli and B.subtilis) with molecular ribo-switch constructs capable of detecting specific target molecules were encapsulated into the multilayers of ionomer silk derivatives assembled in layer-by-layer (LbL) fashion. Silk fibroin modified with lysine [poly-L-Lys (SF-PL)] and glutamic acid [poly-L-Glu (SF-PG)] was used to assemble LbL structures with concave-shapes that served as pads or cushions for the injected cells.  By injecting these silk derivatives on the top of the cells, sandwich structures formed and established stable structures.  The formation of biocompatible, thin (~2 �m) hydrogel-like networks of silk multilayered structures, the viability/activity of cells was maintained.  After long-term storage of such structures, cellular response was induced to maximum fluorescence intensity within one hour of incubation in media supplemented with the target analyte.  This method of forming biocompatible stable platforms for efficient immobilization of cell-based sensors makes ink-jet printing a valuable tool for the rapid fabrication of large-scale multilayer arrays and multiple cell libraries on any substrate with good precision and accuracy.

Ink-jet printed arrays of cell-based sensors in silk hydrogel matrices

247th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.