DNA chips with conjugated polyelectrolytes in resonance energy transfer mode.

We show how to use well-defined conjugated polyelectrolytes (CPEs) combined with surface energy patterning to fabricate DNA chips utilizing fluorescence signal amplification. Cholesterol-modified DNA strands in complex with a CPE are adsorbed to a surface energy pattern, formed by printing with soft elastomer stamps. Hybridization of the surface bound DNA strands with a short complementary strand from solution is monitored using both fluorescence microscopy and imaging surface plasmon resonance.

The promotion of neuronal maturation on soft substrates.

Microenvironmental mechanical properties of stem cell niches vary across tissues and developmental stages. Accumulating evidence suggests that matching substrate elasticity with in vivo tissue elasticity facilitates stem cell differentiation. However, it has not been established whether substrate elasticity can control the maturation stage of cells generated by stem cell differentiation.

Protein biochips patterned by microcontact printing or by adsorption-soft lithography in two modes.

Patterning of proteins is critical to protein biochips. Printing of layers of proteins is well established, as is adsorption of proteins to surfaces properly modified with surface chemical functionalities. The authors show that simple methods based on soft lithography stamps can be used to prepare functional antibody chips through both these routes.