SRM Dilution Calculations 2
Revised for the last time
Today I went to UWPR to make the dilutions. Last night, Laura told me that she diluted our PRTC to 200 fmol/µL, so I had to account for that when making dilutions. The first thing I did was revise my dilution calculations with the new PRTC stock concentration. Because I needed to add more PRTC to each sample, I changed the injection volume from 1 µL to 2 µL for the 10:1 dilution. This means Laura has to pipet 0.375 µL of geoduck, which is less than 0.5 µL. Because Laura and I have pipetted this volume before and it’s only for one sample, I think it is okay. Before I went down, I took 0.1 µL and 0.5 µL pipets from the lab.
Table 1. Revised dilution calculations
|Vial||Dilution Ratio||µg to Inject||µL to Inject||µg oyster Needed||µg geoduck Needed||µL oyster needed ((µg/µL)x15 µL/1 µg/µL)||µL geoduck needed ((µg/µL)x15 µL/2 µg/µL)||PRTC added||µL ACN||Total Volume (µL)|
I then created 25 µL of my pooled oyster solution by adding 5 µL of the samples I selected here.
Using the volumes in Table 1, I prepared the vials by adding my oyster sample, PRTC and ACN. When I got to Vial 6, it was difficult for me to pipet the 1.5 µL I needed, so I made 10 µL of the oyster pool. I finished up the vials and left in the freezer for Laura to add her samples to.