Trypsin-gold nanoparticle conjugates: binding, enzymatic activity, and stability.

Nanomaterials may interact with biomolecules in various ways and change their bioactivities. Here, we report on how gold nanoparticles (AuNPs) affect a most important protease, trypsin. After simple mixing of the trypsin and AuNPs solution the average diameter is 20 nm under enzyme friendly conditions (pH 8.0); the bond between trypsin and AuNPs was detected by UV-vis spectroscopy. The further protease assay of trypsin, before and after mixing with the AuNPs solution, pointed out an improved performance in terms of enzyme activity and stability.