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Separation science: mass spectrometry

Find out what substance is contained in the tablet by carrying out mass spectrometry analysis with Dr Thomas Miller.
OK. So you’ve got the gloves on. Let’s go into the lab.
Hi, Joanna. Natsumi, this is Tom. Hi, Natsumi. Nice to meet you. Nice to meet you as well. So we have a sample for you to analyse. Cool, sounds good. OK? Yeah. I’ll leave you with Tom. Thank you, Donna. OK, Natsumi, what we’re going to do today is analyse the sample using LCMS. The instrument we’re using is a triple quadrupole, and the scan we’ll be using is called selective reaction monitoring, which is NSRM. OK. So if you just follow me, we’ll load up your sample.
So here are the samples, so you can just load those onto the auto-sampler for me. Sure.
And what I will do now is just load on the column. OK. So I’m loading this onto the LCMS, and this is a C18 stationary phase, so we’re doing reverse-phase chromatography, and we’ll be able to separate non-polar or moderately polar compounds. I see.
Right. So now that the column is on the LC, we can start the instrument and start the analysis, which will take about an hour to finish. So we can come back to discuss the results in a while. OK. OK, Natsumi, so I’ve just checked the instrument, and our samples are now run. I’ve just brought up the data here, and we initially suspected that your sample contained MDMA. Yes. So what we’ve done here is we’ve analysed a pure standard of MDMA. So if we look at the top panel here, we’ve got an extracted ion chromatogram, and we’ve got a single peak that elutes that retention time of 3.63 minutes, and it’s also at SRM transition that we would expect for MDMA.
OK. So if we now compare this to your sample, which is this– This is our sample. – Yeah. That’s right. This bottom panel is your sample. We see that we get a single peak again, and it comes out at the same retention time. It’s the same. Exactly the same? Yeah. There is some slight difference. So, your sample is more concentrated than the standard that we’ve run. But it is MDMA, because it’s coming out at the same retention time, and it’s also at the SRM transition. I know. We’ve confirmed it’s MDMA. Yeah. We can confirm it’s MDMA.
So what I’m going to do is I’m just going to print this out for you, and then you can take this data back to Alan - Thank you. - and show him your results. Thank you very much. No problem.
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The Science Behind Forensic Science

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