The manuscript by Bingham and co-workers describes the authors’ experience in using ASAP-MS as part of a university teaching programme, and the complementarity that the technique provides to traditionally used analytical approaches in undergraduate laboratories. The manuscript details the use of ASAP-MS in a range of experiments, demonstrating the additional data obtained as well highlighting the enhanced pedagogical experience for the students. From the work presented, it is clear that ASAP-MS offers a route to more hands-on experience of mass spectrometry for undergraduates, which would be an important development given the ever-increasing use of mass spectrometry in different scientific fields.

The authors may wish to consider the following points:

Page 2, line 28 No hyphen needed between “thirteen” and “undergraduate”

Page 2, line 30 The term “parent ion” is deprecated by IUPAC (please see Murray et al., 2013, Pure Appl. Chem., 85, 1515-1609). There are many instances through the manuscript (including the supporting information), so please change all to “precursor ion”.

Page 3, line 7 The first sentence of the paragraph doesn’t quite make sense. Please amend.

Page 3, line 56 “et al.” is Latin so should be italicised.

Page 4, line 5 Is another point worth making about the Brick-L that it’s not commercially available (to the best of my knowledge). A university is highly unlikely to build an instrument unless it has an active research group in this area, which is low chance given the number of groups that do this work.

Page 4, line 12 I think that the Advion instrument should also be mentioned here. I appreciate that it’s referred to later on, but so as not to show bias in a manuscript with an author from Waters, and the fact that there’s only two commercially available options, the Advion system should also be highlighted.

Page 4, line 19 Hyphen needed between “feature” and “rich”.

Page 4, line 46 Surely “A Waters RADIAN ASAP…”? There is not only one.

Page 4, line 51 Was the bake-out 3 x 1 minute? Or was it a bespoke option of 1 x 3 minutes that isn’t available on the commercially available instrument?

Page 4, line 57 Isn’t the corona pin defined by the number of µA? Is that not 3?

Page 5, line 10 Approximately how long was the rod left for solvent to evaporate?

Page 6, Table 1 There are several points related to the table. Some values are quoted to 1 d.p., and others to the whole number – please be consistent. Is g mol-1 the right unit to use? Wouldn’t u or Da be more suitable? And isn’t the monoisotopic mass more appropriate? Make a big difference for 4.4.2 because of the chlorine atom. And why quote both isotopes for this molecule? Why not quote the 13C isotope for all of the compounds in that case? For 5.2.3, why is the carboxylic acid group represented differently to other compounds c.f. 3.2.3, 4.1.2 etc. And why is the absolute stereochemistry shown for this compound when others also have chiral centres c.f. 5.4.2? For the negative ion data for 5.4.2, IUPAC convention would be to have the polarity of the charge and then the dot to represent the radical, not the other way around as shown.

Page 6, line 60 If analysed straight away, rather than allowing the probe to dry (as described on page 5, line 10), would this enable these more volatile molecules to be detected? Are they being lost during the drying of the probe?

Page 7, line 22 Seems to be a problem with the automated referencing software. Please amend.

Page 7, line 54 “molecular ion” as defined by IUPAC (please see Murray et al., 2013, Pure Appl. Chem., 85, 1515-1609) refers to ions generated through the loss or gain of an electron(s). The authors are describing an even-electron ion in this instance. Please use the term “precursor ion”.

Page 7, line 56 The loss of both oxygen atoms from the ester group would not generate an ion of m/z 136. The m/z 136 ion would have to lose oxygen and gain two hydrogens compared to the m/z 150 ion, which is not possible. There is also no precedent for a carbonyl group to lose its oxygen atom under CID conditions. Please reconsider this interpretation.

Page 8, line 5 The sentence starting “Furthermore, the larger fragments…” doesn’t really make sense. Firstly, is “larger” in this context referring to the mass, or the intensity? Also, the wording suggests that the m/z 121 and m/z 119 are mutually exclusive and one replaces the other under different conditions. This isn’t necessarily the case – the chemistry could be such that they both co-exist, and one doesn’t have to be “instead” of the other. Please can the authors look at rewording this sentence?

Page 8, line 18 The authors use the term “mass fragments”. What other type of fragment are there? What fragments don’t have mass? “fragment ions” would be a more appropriate term here, and should replace other instances of “mass fragments” in the manuscript.

Page 8, line 18 “hard fragmentation” and “soft fragmentation” aren’t conventional mass spectrometry terms. “hard” and “soft” ionisation techniques are often talked about, but these adjectives aren’t usually applied to fragmentation techniques. Please can the authors reword using more commonly used terminology.

Page 9, line 44 Do the authors have any hypotheses as to why the ratio of the molecular ion and the protonated molecule between the student and commercial samples? Perhaps more residual solvent in the student sample providing a source of protons?

Page 9, line 48 Please amend to “…the ether moiety of eugenol.” The moiety is part of the compound, not on it.

Page 10, line 45 Does the m/z 121 ion originate from the aspirin or the salicylic acid?

Page 12, line 16 Isotopes do not show splitting patterns. The signal doesn’t split c.f. signals in NMR spectra whose appearance is dependent on the environment a chemical group is in. The signals arise due to distinct molecules. Please amend the wording here and throughout the manuscript.

Page 13, line 29 Seems to be a problem with the automated referencing software. Please amend.

Page 14, line 5 Some of these ions are common to both spectra e.g. m/z 114, m/z 227. Please amend.

Page 14, line 29 The term “electron impact” is deprecated by IUPAC (please see Murray et al., 2013, Pure Appl. Chem., 85, 1515-1609) as the electrons do not impact the molecule to generate an ion. Please change to “electron ionisation”.

Page 14, line 33 This section would read slightly better if a new sentence was started i.e. “…the analyte molecule. Therefore, it’s unlikely…”.

Page 15, line 30 Need to pluralise “career”.

Page 18, line 3 Mixture of references where all the title words begin with capitals e.g. 11, 12, and others where only first word does e.g. 4, 6. Please consult the journal’s referencing style and use throughout.

Supporting information, Table 1 Why quote molecular mass to one decimal place, and m/z to a whole number? Also, as above, is g mol-1 the correct unit to use for molecular mass? Should it not be u or Da?

Supporting information, HE 3.2 The spelling of “sulphuric” is deprecated by IUPAC, which recommended the spelling “sulfur” many years ago (further details can be found in Cantrill, 2009, Nat. Chem., 1, 333). Please amend all use of sulfur-related names to the correct spelling e.g. sulfuric, sulfate, sulfite etc. throughout the supporting information.

Supporting information, HE 4.2 Won’t m/z 137 in the table be the 13C isotope peak? Without the scale on the y-axis it’s hard to tell, but it looks approximately correct.

Supporting information, Figure 18 “chromatograph” is the instrument. The data generated is a “chromatogram”. Please amend.

Supporting information, References Mixture of references where all the title words begin with capitals e.g. 5, and others where only first word does e.g. 6, 7. Please consult the journal’s referencing style and use throughout.