by
DR » Tue Dec 26, 2017 2:22 pm
EmpowersBane wrote:
...For argument, lets just say my Injection volume is 6 mcl and my sample was prepared by weighing out 2g (2000mg). I know Empower takes the area of sample, divides by average area in bracketing standard and multiplies by conc in component editor but how does it take into account the injection vol/sampleweight when calculating final amount?? I use an external standard, linear through zero.
What units do i put my sampleweight into? I cant seem to grasp that last part where the injection volume and sampleweight plays a part.
Amount is the result of using your standard response and associated concentration to determine how much of a given component is in your sample. (y-b)/m=x, which is the amount in the sample injection. This raw amount is divided by sample concentration (as determined by dilution factor entered), bringing you back to your original sample concentration.
If your injection volumes between standard(s) and sample differ, the reciprocal of the ratio of volumes is used to normalize things.
If you want to enter units into your amounts table along with the concentration(s) of standard(s), make sure that their labels start with a "S" and do so in the right-hand column by starting with a < character ("<mg/mL", for example).
Sample amount units are assumed to be the same as standard units (so use the same units for everything). If you enter sample weights, I *think* that they get thrown in as a divisor to what would otherwise be a regular amount calculation so that you end up with a "per unit" amount.
Hope this helps.
It is usually a good idea to play with some of your standard and sample peak areas and dilutions in a spreadsheet to make sure you and Empower "understand each other" when doing anything new.