Silicon microstructures for high-speed and high-sensitivity protein identifications.

Silicon microtechnology has been used to develop a microstructure toolbox in order to enable high accuracy protein identification. During the last 2 years we developed and applied monocrystalline silicon structures and established new automated protein analysis platforms. The development of a high throughput protein platform is presented where fully automated protein identifications are performed. It includes the reduction and alkylation of the protein sample in a standard 96- or 384-well plate format prior to injection of 1 microl samples into the continuous flow based microtechnology platform. The processed sample is transferred to a microchip nanovial array target using piezoelectric microdispensing. Identification is made by MALDI-TOF MS and a database search. After the initial sample reduction and alkylation period of 50 min the platform can digest and process protein samples at a speed of 100 samples in 210 min. An optional configuration of the platform, operating the dispenser in the 'static mode', enables on-target enrichment of low abundant proteins and peptides e.g. from 2DE samples. This makes detection at the low attomole level possible.