Skip to main content

Advertisement

Table 1 Experimental conditions for LC-MS/MS analyses

From: Analysis of β-N-methylamino-L-alanine (BMAA) in spirulina-containing supplements by liquid chromatography-tandem mass spectrometry

  Method 1: AQC-RPLC-MS/MS Method 2: HILIC-MS/MS
Derivatization AQC none
Chromatography RPLC HILIC
Stationary phase Thermo Hypersil Gold C18 TosohBioscience TSK-gel Amide-80
Column length × I.D. (mm) 50 × 2 250 × 2
Column packing size (μm) 1.9 5.0
Column temp (°C) 20 40
Mobile phase A Water with 20 mM NH4COOH (pH 5 adjusted) Water with 50 mM HCOOH
Mobile phase B Methanol Acetonitrile: Water (95:5) with 50 mM HCOOH
Flow rate (mL/min) 0.40 0.20
Injection volume (uL) 6.0 5.0
Elution conditions 10-40% B in 6 min, to 85% B at 6.1 min, hold at 85% B until 8.5 min. 90 to 60% B in 15 min, hold to 20 min, decrease to 55% B at 21 min, hold to 30 min.
MS Ionization Positive electrospray (Turbospray®) Positive electrospray (Turbospray®)
MS source temp (°C) 450 450
MS ionization voltage (V) 5500 5500
MS orifice potential (V) 70 40
   Relative intensities   Relative intensities
SRM transitions for: Precursor m/z Product m/z CE (V) BMAA DAB AEG Precursor m/z Product m/z CE (V) BMAA DAB AEG
1 BMAA, DAB, AEG 459.2 171.1 35 1.00 1.00 1.00 119.1 102.1 15 1.00 0.40 1.00
2 BMAA, DAB, AEG 459.2 119.1 30 0.28 0.07 0.28 119.1 101.1 20 0.55 1.00 0.65
3 BMAA, DAB, AEG 459.2 289.1 20 0.39 0.13 0.27 - - - - - -
4 BMAA specific 459.2 258.1 30 0.04 na na 119.1 88.1 20 0.29 na na
5 DAB specific 459.2 188.1 35 na 0.02 na 119.1 74.1 25 na 0.11 na
6 AEG specific 459.2 214.1 35 na na 0.02 - - - - - -
7 d3-BMAA 462.2 292.1 20 1.0 na na 122.1 105.1 15 1.00 na na
8 d3-BMAA 462.2 122.1 30 0.7 na na 122.1 88.1 20 0.24 na na
8 mono-AQC BMAA 230.1 171.1 30 na na na na na na na na na
9 di-AQC lysine 487.2 171.1 25 na na na na na na na na na
10 mono-AQC lysine 317.1 171.1 30 na na na na na na na na na