The direct patterning of biomolecules on a solid substrate can be achieved using microcontact printing, a method that has been very successfully adopted for the precise and gentle transfer of proteins and lipid bilayers from stamp to substrate in 1 s, without loss of biological activity. The image shown was produced by patterning 16 different proteins onto the polystyrene surface of a cell culture dish using a stamp inked by means of a microfluidic network.

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High‐resolution arrays of antibodies can be prepared in a highly parallel manner by a combination of affinity purification and microcontact printing. Arrays with lateral dimensions of between 100 and 3 μm were prepared by using planar, affinity stamps that were patterned by using various soft lithographic techniques. The fluorescence microscopy image shown demonstrates the placement of anti‐chicken and anti‐goat antibodies on a glass substrate from a stamp.

The connection between the mechanisms of protein adsorption on nanoparticles and the structural and functional properties of the adsorbed protein often remains unclear. We investigate porcine hemoglobin adsorption on silica nanoparticles, and we analyze the structural and functional modifications of adsorbed hemoglobin by UV-vis spectrophotometry, circular dichroism, and oxygen binding measurement. The structural analysis of adsorbed hemoglobin on silica nanoparticles reveals a significant loss of secondary structure and a preservation of the heme electronic structure. However, adsorbed hemoglobin retains its quaternary structure and exhibits an enhanced oxygen affinity with cooperative binding. Moreover, the structural and functional modifications are fully reversible after complete desorption from silica nanoparticles at pH 8.7. The tunable adsorption and desorption of hemoglobin on SNPs with pH change, and the full control of hemoglobin activity by pH, temperature, and the addition of inorganic phosphate effectors opens the way to an interesting system whereby protein adsorption on nanoparticles can allow for full control over hemoglobin oxygen binding activity. Our results suggest that adsorption of hemoglobin on silica nanoparticles leads to a new structural, functional, and dynamic state with full reversibility in a way that significantly differs from protein denaturation.