Slashes or hyphens for combined methods
There is a great deal of confusion on the use of slashes, hyphens, spaces, or no spaces to indicate the combination of techniques, particularly when acronyms and abbreviations are used. The Chicago Manual of Style tends to favor hyphens due to the ambiguity of the slash, which has connotations of "and/or" in many instances. The ACS Style Guide makes no specific recommendations but gives examples of slashes, hyphens, spaces and no spaces in examples. The American Institute of Physics Style Manual makes no specific recommendation but contains no examples of the slash usage. David Sparkman calls for separate connotations of the slash and hyphen with the former separating techniques and the latter instruments. Rapid Communications in Mass Spectrometry has called for a slash to separate combined methods and a hyphen to highlight a particular component such as the ionization method (Sparkman instead suggests a space to separate the ionization method). The Definitions of Terms Relating to Mass Spectrometry (IUPAC Recommendations 2013) suggests the use of the hyphen but indicates that the slash can also be used.
|QUOTED TEXT FROM IUPAC RECOMMENDATIONS 2013|
|The hyphen, or alternatively the slash (forward stroke), can be used to indicate combined methods such as gas chromatography separation combined with mass spectrometry detection. Thus, the above combination can be written as gas chromatography-mass spectrometry or alternatively as gas chromatography/mass spectrometry. The corresponding abbreviations are GC-MS or GC/MS. The first use of a hyphen to indicate the combination of a separation method with mass spectrometry was in the early 1960s , and the use of a slash separator was in the 1970s . The term “hyphenated techniques” was coined in 1980 . Currently, hyphens and slashes are used interchangeably . The journal Rapid Communications in Mass Spectrometry has in the past recommended that the combination of two analytical techniques be designated by a slash (Conventions adopted by RCM in Advice to Authors. Rapid Commun. Mass Spectrom. 17, Issue 1 (2003)). A recent Journal of Chromatography glossary also favors this usage . IUPAC recommends that hyphens be used to describe variants of separation techniques, for example, gas-liquid chromatography and pyrolysis-gas chromatography . The authors of this document are evenly split in their preference for hyphen or slash. For consistency with the prior recommendations, we use the hyphen for combined techniques but note that the slash can be used interchangeably.|
|From Definitions of Terms Relating to Mass Spectrometry (IUPAC Recommendations 2013); DOI: 10.1351/PAC-REC-06-04-06 © IUPAC 2013.|
Other recommendations are given below.
Chicago Manual of Style
The 16th edition of the Chicago Manual of Style indicates that slashes are most commonly used to indicate alternatives in the "and/or" formulation, for example "Hercules/Heracles."(CMOS 6.104) The CMOS also indicates that the slash is occasionally use to indicate "and" as in "Jekyll/Hyde." The "per" and "divided" by meanings are also noted.
The CMOS big table of hyphenation rules states that two nouns indicating two functions (the first noun doesn't modify the second) are hyphenated in both the noun and adjective forms.(CMOS 7.85)
American Chemical Society Style Guide
Chapter 10 of the ACS Style Guide discusses editorial style including the use of hyphens and abbreviations.
Specific rules for combined methods are not given, but there are several examples in a list of abbreviations use space, no space, hyphen, en-dash, or slash. Surprisingly, neither GC-MS nor LC-MS are given in the list. Hyphen proponents will point to CE–MS, but slash advocates will point to CP/MAS.
Specific examples are: capillary electrophoresis mass spectrometry is abbreviated CE–MS, but cross-polarization/magic-angle spinning is abbreviated CP/MAS, but also CP-MAS, CP–MAS, CPMAS, and CP MAS are also indicated. Other examples are fast atom bombardment mass spectrometry (FABMS), Fourier transform ion cyclotron resonance (FTICR), Fourier transform infrared (FTIR, FT/IR, FT-IR, and FT IR), glow discharge mass spectrometry (GDMS), high-resolution mass spectrometry (HRMS), isotope dilution mass spectrometry (IDMS), isotopic ratio mass spectrometry (IRMS), laser desorption mass spectrometry (LDMS), matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS and MALDI-TOF MS), plasma desorption mass spectrometry (PDMS), pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS), time-of-flight mass spectrometry (TOFMS TOF MS), triple-quadrupole mass spectrometry (TQMS).
American Institute of Physics Style Manual
The AIP style manual uses the hyphen exclusively for combined terms.
Mass Spectrometry Desk Reference
David Sparkman in his Mass Spectrometry Desk Reference recommends the use of the slash to indicate the combination of techniques and the hyphen to indicate the combination of instruments. Thus
- Gas chromatography/mass spectrometry (GC/MS)
- Gas chromatograph-mass spectrometer (GC-MS)
- time-of-flight mass spectrometry (TOFMS)
- time-of-flight mass spectrometer (TOF-MS)
Ionization methods are set apart by a space, for example
- electron ionization time-of-flight mass spectrometry (EI TOFMS)
Rapid Communications in Mass Spectrometry
The journal Rapid Communications in Mass Spectrometry has in the past given instructions to authors on combined techniques. For example, from the July 12, 2009 RCM:
The Rapid Communications in Mass Spectrometry author guidelines state
- "A single analytical technique, or a type of instrument, is abbreviated without hyphens. Thus, TOFMS, FTICRMS."
- "A hyphen is used when highlighting a particular component or feature of an instrument or technique. Thus, MALDI-TOFMS, ESI-MS/MS. When 2 or more different analytical techniques are coupled in tandem, this is represented by a solidus placed between the abbreviations for the techniques. Thus we write Py/GC/EI-MS, CZE/TOFMS."