Micro-Contact Printing of different biomolecules in one step using deformable Poly(dimethylsiloxane)-based stamps

The localized deposition of molecules such as DNA or proteins at the micron or submicron scale on solid supports is a crucial step in the fabrication of advanced biochips and lab on chip devices. Among the different methods for delivering biomolecules along well defined patterns, micro-contact printing (muCP) is emerging due to its low implementation cost, its ability to produce sub-micron patterns and large surface processing. However, one severe limitation of this technique is that only one type of biomolecule can be printed in one step because generally the stamp is inked everywhere with the same biomolecule. When different biomolecules are to be patterned it is then necessary to sequentially print them which rises the problem of the alignment between the different levels. Aligning elastomeric stamps made of PolyDiMethylSiloxane-based (PDMS) materials is not easy due to the deformability of the stamp and its high adhesion on flat surfaces. In this work a new method for generating self-aligned patterns of different biomolecules using PDMS stamps is proposed, exhibiting several levels of topography.