Duplicate values in mapping file

Hi All,

Back again with another mapping file question. So the protocol I have is as follows: I have a 96 well plate where each sample in that plate could be added to up to 7 master mixes in a 384 well plate. My input file contains the sample information, and which samples need which master mix. From there I have the information separated into 7 different sequences based on the master mix, which may or may not contain the same samples coming from the 96 well plate. For instance, the sample in well A1 needs master mixes 3 and 5, so both the sequences for MM3 and MM5 contain A1. The robot then loads all the master mixes first, outputs a mapping file for those transfers, and then moves to adding samples separated by master mixes. So the robot transfers all the samples needed for MM1, then cycles back to the 96 well plate to do the ones for MM2, and so on, and is supposed to output a second, separate mapping file for these transfers. The issue arises when samples are used more than once (in this test protocol twice) - the mapping file notes both transfers, but then copies the first transfer twice

In the simulation run, the sample transfers are not duplicated, so I know its not the robot double adding things. I’m trying to figure out if there is a setting I’m missing, or if its a bug. Any advice would be greatly appreciated, thanks!

Hi @InnerKK,

What you’re experiencing here is similar to the total volume that gets printed in the mapping report (see this thread). Tracking data in the Vector Database is stored based on Labware ID, not sequence name. As such, when a mapping report is generated for a target sequence, it is actually pulling all data related to the Labware ID, not just the given sequence name. This leads to the duplicates that you’re seeing in your output file, as you are using different sequences for pipetting, but all referencing the same Labware ID and positions. Like the linked thread suggests, a way to work around this is by using the Remove Labware function between rounds of pipetting to clear the Database of the previous pipetting data. If your labware has a barcode, then you’ll also want to use a Set Labware Barcode function after the remove to reassign the corresponding barcode.

Thank you,
Dan

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Awesome, thank you so much Dan! I had a feeling it was something simple I was missing.

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