Is there any contamination from the silicone seal?
We tried to find silicone oligomers but have never seen any in the mass spectrum.

How does the sensitivity of the DigestPro MSi compare to the DigestPro MS/DigestPro 96?
The principle of operation as well as most of the parts are identical and the digestion sensitivity is therefore similar. The DigestPro MSi is a bit slower as the DigestPro 96 as it has only one probe, but most of the time is reaction time anyway.

How is contamination avoided?
Gel slices are held in flow-through reaction vials. Reagents are exchanged by nitrogen pressure. The gel slices and peptides resulting from digestion are never touched by a pipetting probe.

How is evaporation controlled in the DigestPro MSi?
The reaction vials are covered by a sealing membrane throughout the procedure. Only a small hole is open for reagent delivery.

How does the DigestPro MSi control the temperature?
The 96 well reaction plate is held in a thermostated rack which can be heated to temperatures of up to 70°C.

Are all samples treated the same?
Standard protocols employ the same procedure for all samples but some variation can be programmed.

What is the time required for a run?
A complete run with washing, reduction, alkylation, rehydration, digestion and peptide elution takes about 10 hours.

Is there positive sample identification?
Samples are introduced in the DigestPro MSi in 96 well plates and digests are obtained in the same format without re-arranging.

Does the DigestPro MSi have to be operated in a fume hood?
No, the instrument comes with a self-contained cabinet. An exhaust tube leading to a ventilation system must be connected to an outlet provided.

Does INTAVIS supply reagents?
As high quality buffers are available from several sources, INTAVIS does not supply reagents. However, we supply reaction and collection plates as well as other consumables.

What determines the limit of detection in the DigestPro MSi?
The detection limit is determined by the signal-to-noise ratio in the mass spectrum. Factors like contamination by ubiquitous proteins or adsorption of peptides to plastic surfaces play a major role. Sample enrichment using Zip Tips as used in the DigestPro MSi has been shown to enhance the sensitivity significantly.

What volumes can be handled by the DigestPro MSi?
The reaction vials have a volume of 200 µl. Wash steps use 60 to 100 µl, the digestion is performed in 15 µl. Volumes down to 10 µl can be dispensed without touching the gel slices. In the MALDI procedure a different needle is used which can handle volumes between 0.5-100 µl.