FAQ – Technical
Does the ResPep SL 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.
Can I use bulk reagents?
Yes, the ResPep SL was designed for economical operation. Solvents and activator are bought from standard, recommended suppliers. Only amounts needed for a particular synthesis are weighed, dissolved and used.
FAQ – Application
Do the amino acids have to be pre-activated for CelluSpots™synthesis?
No, the ResPep SL can activate amino acid derivatives specifically for each cycle. There is a dedicated activation vial for each amino acid. Of course, pre-activated amino acids can also be used.
Will the individual discs be deprotected in the instrument?
Yes, the ResPep SL spots piperidine solution on the discs to take the Fmoc protection group off in each cycle. The synthesis plates with individual discs can stay in the instrument for the entire synthesis.
How are the discs washed and dried for the next coupling?
The discs is clamped tightly in a 384-well synthesis plate. The bottom has tiny holes to remove solvent by vacuum aspiration. Solvent is delivered on the upper face of the discs and pulled through by vacuum. A longer extraction time is being applied to remove ethanol from the final wash and to dry the discs.
Is the rinsing action sufficient if a full set of peptides is built on the discs?
Yes, the flow-through mode of washing is very effective and makes economic use of the solvents.
Can we still use Bromophenol blue (BPB) to monitor the reactions?
The ResPep SL can be programmed to deliver BPB at the appropriate steps in the cycle to stain amino groups on the peptides assembled. The stain is removed with the next coupling reaction as it is done in manual procedure, too.
Is there any possibility of piperidine carryover?
As piperidine is used in a very large excess it must be removed thoroughly. The washing procedure is designed to remove all traces of the reagent before the next coupling will be started.
What is the synthesis time for two sets of 384 each 10-mer peptides?
With a recommended double coupling of 2x30 min, 2x5 min deprotection and all washing and drying steps, the total cycle time is about 2.5-3 hours and the two sets of 10mers would be assembled in a little more than a day.
Can the synthesis be interrupted and started again?
The ResPep SL can be stopped and re-started at any time. Several convenient options allow manual procedures (e. g. Bromophenol blue staining or introduction of very unusual derivatives) and safe re-starting in any cycle.
FAQ – Software
Does the ResPep SL require a computer?
The ResPep SL is operated from a standard PC. The graphical software takes care of derivative and sequence definition, generation of peptide sequences from parent protein sequences, calculation of reagent consumption, operation of the instrument and generation of a log file of operation.
How much programming is required to operate the ResPep SL?
During everyday use you just define the peptide sequences, select a protocol, load the work area and start the synthesis. More experienced users can modify the pre-defined protocols and adapt them to their specific needs. The relevant parameters of the protocol are accessible in the software.
Do I have access to all synthesis parameters?
The synthesis cycle is composed of individual tasks of the robot. The software lets you have full access to all relevant parameters and you can modify existing methods or create new procedures.
Is there a record of what the instrument does?
All instrument operations are automatically recorded to the computer hard disc. The files can be opened by standard text editors.