Micropatterning of inorganic precipitations in hydrogels with soft lithography

This paper presents two convenient soft-lithographic techniques (membrane transfer and microfluidic deposition) for the generation of micropatterns of inorganic precipitations in hydrogel plates. Both techniques use polydimethylsiloxane (PDMS) as the prime material for patterning; they are complementary to each other for the formation of different types of patterns that have a short or long x/y ratio. All created patterns are half-embedded in the hydrogel substrate to give a topographically flat surface. Three inorganic salts (calcium phosphate, barium sulfate and barium carbonate) are used as model for the demonstration of the patterning process. (C) 2008 Elsevier B.V. All rights reserved.