# ACD/Labs Blog

## Mass Spec 1100101—Data and the Mass Spectrometrist

ACD/Labs is launching a new podcast! The Analytical Wavelength will cover industry trends and topics for scientists working with analytical data. Read on for more insights about data and the mass spectrometrist, and a link to listen to Episode 1.

## 5 things you need to STOP doing in your lab | Gain time and be awesome at your job

There just doesn't seem to be enough hours in the day to get everything done. There are ways to gain time and be able to do more but they can be difficult to identify because until we’re exposed to them we carry on as we always have. If you are still doing any of the things discussed here, then there are ways you can gain hours in your day and even do your job better than you are right now!

## Logic Puzzle #43: Is Signal Intensity on a Mass Spectrum Problematic? … Solution

The warning flag for this puzzle is evident in the intensities of the signals. For an unknown compound, the TOF-ESI+ mass spectrum below shows the expanded region around four isotope clusters at m/z 300.336 ([M+H]+), 322.307 ([M+Na]+), 599.672 ([2M+H]+) and 621.611 ([2M+Na]+). The intensities of the 13C isotopes (i.e. the [M+1] signal) vary between 40...

## Logic Puzzle #43: Is Signal Intensity on a Mass Spectrum Problematic?

A key element in data interpretation is to identify any warning flags. Warning flags can help a chemist differentiate good data from bad data. For an unknown compound, the TOF-ESI+ mass spectrum below shows the expanded region around four isotope clusters at m/z 300.336 ([M+H]+), 322.307 ([M+Na]+), 599.672 ([2M+H]+) and 621.611 ([2M+Na]+). Are the intensities...

## Logic Puzzle #42: How to Convert to PPM for NMR and MS Data? … Solution

Many analytical data rely on common calculations. This solution shows the formula used in the calculations. NMR and MS data were collected on two unknown compounds. The TOF-MS data shows the [M+H]+ at m/z 300.0000 and 600.000 at an error of 0.001 Da. The 500 MHz 1H NMR spectrum shows two chemical shifts at 1500.00...

## Logic Puzzle #42: How to Convert to PPM for NMR and MS Data?

Many analytical data rely on common calculations. This puzzle covers one such common calculation. NMR and MS data were collected on two unknown compounds. The TOF-MS data shows the [M+H]+ at m/z 300.0000 and 600.000 at an error of 0.001 Da. The 500 MHz 1H NMR spectrum shows two chemical shifts at 1500.00 and 3000.00...

## Logic Puzzle #41: Using MS TOF data to Determine the Molecular Formula … Solution

Working on poorly collected data is not fun. It can be frustrating and time consuming. A good LC-MS+ TOF dataset is consistent across a peak and exhibits a mass measurement accuracy of < 5 ppm. The TOF data below shows a significant variation across the peak m/z 205.136 to 205.076 to 205.096 (range m/z 205.106...

## Logic Puzzle #31: Are the Signals Related? … Solution

To identify co-eluting components on a chromatogram, one searches for any distinct differences between the components. There are basically three criteria to check the XICs (extracted ion chromatograms) for to confirm whether the m/z signals pertain to the same component: line shape, signal apex and retention time range. The XICs for m/z 188.1 and 205.1...

## Logic Puzzle #31: Are the Signals Related?

Sorting out what compounds are present in a mixture is a difficult task. The process is further complicated when the compounds co-elute on a chromatographic run. An LC/MS (ESI+) was collected for an unknown sample comprising of small organic molecules. The total ion chromatogram (TIC shown in black) shows a signal at 2.86 minutes. The...

## The Bosutinib Isomer- A Case for NMR ASV?

I've already described the Bosutinib fiasco in my last entry, and finished with a teaser that we would be back for more commentary on this topic.  We plan a series of tests of our algorithms and systems to see if our software could have been used to prevent a situation like this. The main question...