Agilent quadrupole — time of flight 6550 mass spectrometer with iFunnel ion optics and ESI source with Jet Stream technology: scan range from 20 to 10,000 m/z, mass accuracy < 1 ppm, 20k resolution for 322 m/z or 40k for 2,722 m/z. Signal-to-noise for 1 pg reserpine (609.2807 m/z) = 1000:1. It can be coupled with capillary electrophoresis (CE 7100) or UHPLC (1290 Infinity II) using MassHunter software.