Why am I getting a “valid sample count” error in my Reagent Distribution command?
Can you use a formula in “Number of Samples” field?
You can, make sure your sample number Variable has a valid default number under the Variables tab. For example an integer variable equal to 0 will produce a negative number of samples when you subtract 48 from it.
So the main questions are the following… how many aliquots do you need and how many plates would you like to pipette into and does it need to be in a loop?
- NO LOOP: number of samples is > 48 and plates are named the same with increasing number S1_[001] & S1_[002] etc. then you can just add any number between 1 and 96 (or more of you have > 2 plates) for the ‘Number of samples’ value. Fluent Control will automatically jump to the next plate/holder. It will take new tips for the second plate/holder.
- Make sure the plates following S1_[001] are available for pipetting on the worktable before starting the Reagent Distribution command. If not, there will be an error.
- NO LOOP: If you have 2 or more plates that are a identical (ie. each holding 20 samples at the same positions) then you can use the replicate option under ‘advanced’ and then it will duplicate the pipetting action of the first into the following plates with the S1_[002] etc numbers. It will take new tips for the second plate/holder.
- LOOP: you can use an if and else statement to count the number of samples that are in the plate for each loop. If you have full plates except for the last one just do the following
- check with if statement the number of samples needed per loop. Place the if statement in loop before distribution
- if : (NumberOfCycles = LoopCounter) AND ((totalnumberofsamples MOD 48) <> 0)
- SET VARIABLE: SamplesInLoop = (totalnumberofsamples MOD 48)
- else
- SET VARIABLE: SamplesInLoop = 48
This last one can be all put into a single variable with one line of code as well. Then you can remove the scripts if/else statements and just a a single ‘SET VARIABLE’ line in the script, but I’d have to dig it up. If you really need it let met know.
And for some additional info. I always get errors if I predefine the variables and they are larger then the amount of positions in the plate/holder (in this case > 48). FluentControl does a check to see if it can pipette the samples and with the number of samples. But with the check it calculates that it can not pipette into a single plate so it throws an error. But then again the SmartCommand can handle the cross-over into multiple plates. If you use the ‘Variable’ option from Touch Tools or have a fixed ‘Set variable’ in the script to update the value to something > then the amount in the plate then it works like a charm.
An alternative is to write max(AliquotNum-48,0).
This will resolve the potential for negative numbers and therefore should make it work.
Thank you for all the feedback. I was able to resolve by using SET VARIABLE to define new variables for plate 1 vs plate 2. My script uses reagent distribution to aliquot 8 solutions from 8 troughs to many SBS boxes. Each SBS box holds 48 tubes that have to be decapped, dispensed, and recapped before moving to the next SBS box. Its working like a charm now.